Jupiter is huge. To find out how huge, use the Internet to conduct research on both Earth and Jupiter. See how their diameters and surface areas compare. Now imagine that Earth is as big as Jupiter. In what ways do you think our civilization would develop differently? Would it bring more chaos into our troubled history or make us more civilized?
Jupiter [1]
Earth [2]
Ratio
Mass (10 24 kg) 1,898.6 5.9736 317.83
Volume (1010 km3) 143,128 108.321 1321.33
Radius at Equator 71,492 6,378.1 11.209
Radius at Polar 66,854 6,356.8 10.517
Gravity 24.79 9.80 2.530
Surface Pressure >>1000 bars 1014 mb
Surface Density 0.16 kg/m3 1.217 kg/m3
Total mass of Atmosphere NA 5.1 x 1018 kg
Atmospheric composition (volume) Molecular hydrogen (H2) - 89.8%; Helium (He) - 10.2% 78.08% Nitrogen (N2), 20.95% Oxygen (O2)
Average Temperature 165 K (-108 C) 288 K (15 C)
Wind Speeds <30 LAT Up to 150 m/s
>30 LAT Up to 40 m/s 0 to 100 m/s
The question that I may ask myself if Earth is as large as Jupiter, my conclusion would be gravity force would increase. If the orbit and tilt doesn’t change, it wouldn’t change our 24 hour day, but it would give Earth more time zones. As far as increased gravity force, would our body build be different to compensate for the increased gravity force? Yes, people would weigh more and possibly be shorter. Another question that I may have how does the massive size of Earth affect the moon. I think it is possible that the moon would be closer to Earth due to gravitational pull. The tides would possible be out of sync; therefore, our weather may change, because of the weaker gravitational pull from the moon. If everything stayed the mostly the same, except our body build, time zones, and weather changes, I believe we have more exploration, more resources to sustain ourselves such as oil, fossil fuel, uranium etc. We could have more solar power and wind power, because of the surface area. We would be less dependent on other countries to supply our resources such as oil. We would develop high tech technology quicker such as military tactical high energy lasers, because the resources to create those are available in abundance. There may be a more precious metal than gold, because Jupiter is composed up from Star elements. There may be stronger metals than Osmium. We could even have more continents equal less chaos. It would be possible that countries that cause chaos; distance can separate us with them by a larger margin. All and all, things would pretty much stay the same unless the effects of the increased Earth’s gravity pull causes problems with other orbiting objects in space being attracted to Earth causing collisions which may upset our whole ecosystem on Earth. Also as stated in our lecture notes, if the internal temperature rises, because of increased gravitational force which the Earth may have with its massive size than all bets are off for life as we know it. There wouldn’t be any civilization unless adaptation took place to shelter us from the extreme climate.
Tuesday, January 04, 2000
Monday, January 03, 2000
Earth-moon binary
will explain the four scenarios astronomers consider for Earth-Moon binary system formation. Moreover, this paper will tell what the main points of each scenario are including modern view and why that is. For the second section of atmosphere composition and characterizes, this paper will describe some of the important factors. These important factors tell the shaping, the surface and atmospheric conditions for the inner region planets and Earth's moon. Earth's moon is twice the size of Mercury.
There are four scenarios astronomers considered for the Earth-Moon binary system formation which are the following: the adopted-cousin theory, the sister theory, the daughter theory and the chip-off-the-old-block theory. The adopted cousin theory says that a small planet was captured by Earth's gravity. The sister theory says it is a double planet. The daughter theory states the moon broke apart from the spinning original Earth also known as primordial Earth. The chip-off-the-old-block theory was originated by computers simulation of the solar system. Billions of years ago, the evolving Earth had nearby neighbors called planetesimals (large mountain sized debris that was orbiting around Earth). I like the bull’s-eye concept in the book. From the initial supernova gave birth to the solar nebula with its orbiting cloud of gases and other elements such as iron, magnesium and sulfur. There was ice crystals that formed water molecules and combined over millions of years. The orbiting cloud of elements contained gases such as hydrogen, helium, oxygen, nitrogen, and carbon and other elements such as iron, silicon, magnesium and sulfur. The lighter gases evaporated from the sun’s radiation. It depended on the distance from the sun; which has eventually left the heavier elements such as rocks and metals which then formed the planetesimals that formed Mars, Mercury, Venus and Earth. Planetesimals were made in million years of evolution. It was the collision of one of these planetesimals with Earth which caused spewing matter from the Earth crust and material from the planetesimals to fly into space. Scientists have concluded the moon is actually a by-product of this earlier collision. To substantiate this theory, moon samples were obtained from Astronauts and other space exploratory devices. Moon rock is different from Earth rock. The chip-of-the-old block has become a de-facto modern theory accepted today. The chip-off-the-old-block theory pretty much debunks the other three theories. (Universe and Beyond, pp 22-23, 2004)
There are important factors that shape the surface and atmospheric conditions on the four inner region planets Earth-Moon, Mars, Venus and Mercury. In the following paragraphs, I will address these factors.
The Earth is the only planet to this day known to have life. There are three factors that helps maintain Earth's atmospheric composition which are as follows: the decomposition of the air molecules that takes place from the Sun's rays, the volcanic activity and the Earth's gravity. Over the early years, Earth had been bombarded by the elements from space and gradually over time, volcanic activity and collisions with comets has provided the Earth with atmospheric gases. Gravity helps maintain the gases and how much escapes through evaporation from the Sun's rays; therefore, Earth has been blessed with just the right atmospheric chemistry in order to maintain life. As far as geological landscape, the Earth landscape has evolved over the years, because of the wind, the rain, the volcano activity. We now have oceans, rivers, streams, mountains, and vegetation that prospers on Earth as we know it. The Earth's temperature is mostly maintained through our permeable cloud cover, Earth's mass and axis tilt and the atmospheric exchange of gases. (Universe and Beyond, pg 24, pp 36-37, 2004)
The moon has no atmosphere, no gases and minimal gravity to maintain its environment. If once there was volcanic activity on the moon, any gases derived from that volcanic activity would dissipate into space. This is mostly due to the moon's minimal gravity and the sun's assistance with evaporation. The moon is pretty much a battle scared, lifeless Antarctica. The temperature varies from space cold in the hemispheric section away from the Sun compared to sizzling hot in the hemisphere facing the Sun. (Universe and Beyond, pp 22-24, 2004)
The Mars atmosphere is less than 1% of Earth's of which carbine dioxide pretty much fulfills the 1%. Ultra-violet light dominates the planet due to the thin atmosphere. The temperature on Mars is cold all year around. In the winter, it is so cold, the atmosphere forms frozen CO2 crystals. It is obvious that there is no liquid form on Mars. Again, the temperature is relevant the thin atmospheric radiation exchange from the Sun. The terrain has a combination of sand dunes, canals, and rock surfaces. Mars is very windy especially in summer which might have gust of 300 KM per hour. Through satellite and pictures taken from robotic rovers, the landscape takes on a orange like hue. This is because the dust particles are stirred up by this windy planet. There is evidence that the planet once held liquid, but at present, scientists believe it is frozen deep into the ground. However, there are signs at one time liquid water did exist since space rovers have recovered sedimentary rock specimens which can easily be found in Earth's lakes and streams. One interesting fact about Mars, is that the tilt of the axis point is closely related to the Earth's. A day in Mars is 24.6 hours vs. Earth's 24 hours. Mars has a larger orbit area; therefore, one year on Mars equals 1.9 Earth years.
Mars is ½ the size of Earth, but 1/10 its mass. (Universe and Beyond, pp 24-30, 2004)
Venus, not like the Roman Goddess Venus, is comparable to Earth in size, mass and surface gravity; however, the temperature far exceeds our boiling point at 460 degrees Celsius hotter than melting lead. The atmosphere is 90% denser than Earth's and composed with mostly carbon dioxide. Since the atmosphere is so dense with carbon dioxide ,the constant volcanic activity produces additional gases enough to produce a greenhouse effect. This greenhouse cloud covering in the upper atmosphere then traps the gases and prevents the sun's infrared radiation from escaping. This makes the planet sizzling hot. The landscape is dominated with active volcanoes. The rotation of Venus is so slow that a day for Venus is equal to 59 Earth days, and the nights are equally long. The snail like rotation does not provide a magnetic field like the Earth's rotation does. (Universe and Beyond, pp 30-33, 36, 37, 2004)
Mercury, the closest to the sun, has temperatures of 400 degrees Celsius. Mercury's atmosphere is completely missing. It also has one third the Earth's gravity. Mercury is half the size of the moon. The landscape looks very much like the moon cratered by the insults of space debris. Mercury has little gravity and rotates slower than Venus. It rotates its axis three times the same time it orbits the Sun twice. One Mercury day equals 176 Earth days. (Universe and Beyond pp 38-39, 2004)
This paper showed the four scenarios astronomers consider for the Earth-Moon binary system formation. Second it showed the main points of each scenario are including modern view and why that is. The paper also concludes the atmosphere composition and characterizes, and described some of the important factors including shaping, the surface and atmospheric conditions.
References
Dickinson, T. (Ed.). (2004). "Chapter 2"
The Universe and Beyond, 4th Edition. (pg 22-23) Canada: Firefly Book, Inc.
Dickinson, T. (Ed.). (2004). " Chapter 2"
The Universe and Beyond, 4th Edition. (pg 24) Canada: Firefly Book, Inc.
Dickinson, T. (Ed.). (2004). " Chapter 2"
The Universe and Beyond, 4th Edition. (pg 36-37) Canada: Firefly Book, Inc.
Dickinson, T. (Ed.). (2004). " Chapter 2"
The Universe and Beyond, 4th Edition. (pg 24-30) Canada: Firefly Book, Inc.
Dickinson, T. (Ed.). (2004). " Chapter 2"
The Universe and Beyond, 4th Edition. (pg 30-33) Canada: Firefly Book, Inc.
Dickinson, T. (Ed.). (2004). " Chapter 2"
The Universe and Beyond, 4th Edition. (pg 36) Canada: Firefly Book, Inc.
Dickinson, T. (Ed.). (2004). " Chapter 2"
The Universe and Beyond, 4th Edition. (pg 37) Canada: Firefly Book, Inc.
Dickinson, T. (Ed.). (2004). " Chapter 2"
The Universe and Beyond, 4th Edition. (pg 38-39) Canada: Firefly Book, Inc.
There are four scenarios astronomers considered for the Earth-Moon binary system formation which are the following: the adopted-cousin theory, the sister theory, the daughter theory and the chip-off-the-old-block theory. The adopted cousin theory says that a small planet was captured by Earth's gravity. The sister theory says it is a double planet. The daughter theory states the moon broke apart from the spinning original Earth also known as primordial Earth. The chip-off-the-old-block theory was originated by computers simulation of the solar system. Billions of years ago, the evolving Earth had nearby neighbors called planetesimals (large mountain sized debris that was orbiting around Earth). I like the bull’s-eye concept in the book. From the initial supernova gave birth to the solar nebula with its orbiting cloud of gases and other elements such as iron, magnesium and sulfur. There was ice crystals that formed water molecules and combined over millions of years. The orbiting cloud of elements contained gases such as hydrogen, helium, oxygen, nitrogen, and carbon and other elements such as iron, silicon, magnesium and sulfur. The lighter gases evaporated from the sun’s radiation. It depended on the distance from the sun; which has eventually left the heavier elements such as rocks and metals which then formed the planetesimals that formed Mars, Mercury, Venus and Earth. Planetesimals were made in million years of evolution. It was the collision of one of these planetesimals with Earth which caused spewing matter from the Earth crust and material from the planetesimals to fly into space. Scientists have concluded the moon is actually a by-product of this earlier collision. To substantiate this theory, moon samples were obtained from Astronauts and other space exploratory devices. Moon rock is different from Earth rock. The chip-of-the-old block has become a de-facto modern theory accepted today. The chip-off-the-old-block theory pretty much debunks the other three theories. (Universe and Beyond, pp 22-23, 2004)
There are important factors that shape the surface and atmospheric conditions on the four inner region planets Earth-Moon, Mars, Venus and Mercury. In the following paragraphs, I will address these factors.
The Earth is the only planet to this day known to have life. There are three factors that helps maintain Earth's atmospheric composition which are as follows: the decomposition of the air molecules that takes place from the Sun's rays, the volcanic activity and the Earth's gravity. Over the early years, Earth had been bombarded by the elements from space and gradually over time, volcanic activity and collisions with comets has provided the Earth with atmospheric gases. Gravity helps maintain the gases and how much escapes through evaporation from the Sun's rays; therefore, Earth has been blessed with just the right atmospheric chemistry in order to maintain life. As far as geological landscape, the Earth landscape has evolved over the years, because of the wind, the rain, the volcano activity. We now have oceans, rivers, streams, mountains, and vegetation that prospers on Earth as we know it. The Earth's temperature is mostly maintained through our permeable cloud cover, Earth's mass and axis tilt and the atmospheric exchange of gases. (Universe and Beyond, pg 24, pp 36-37, 2004)
The moon has no atmosphere, no gases and minimal gravity to maintain its environment. If once there was volcanic activity on the moon, any gases derived from that volcanic activity would dissipate into space. This is mostly due to the moon's minimal gravity and the sun's assistance with evaporation. The moon is pretty much a battle scared, lifeless Antarctica. The temperature varies from space cold in the hemispheric section away from the Sun compared to sizzling hot in the hemisphere facing the Sun. (Universe and Beyond, pp 22-24, 2004)
The Mars atmosphere is less than 1% of Earth's of which carbine dioxide pretty much fulfills the 1%. Ultra-violet light dominates the planet due to the thin atmosphere. The temperature on Mars is cold all year around. In the winter, it is so cold, the atmosphere forms frozen CO2 crystals. It is obvious that there is no liquid form on Mars. Again, the temperature is relevant the thin atmospheric radiation exchange from the Sun. The terrain has a combination of sand dunes, canals, and rock surfaces. Mars is very windy especially in summer which might have gust of 300 KM per hour. Through satellite and pictures taken from robotic rovers, the landscape takes on a orange like hue. This is because the dust particles are stirred up by this windy planet. There is evidence that the planet once held liquid, but at present, scientists believe it is frozen deep into the ground. However, there are signs at one time liquid water did exist since space rovers have recovered sedimentary rock specimens which can easily be found in Earth's lakes and streams. One interesting fact about Mars, is that the tilt of the axis point is closely related to the Earth's. A day in Mars is 24.6 hours vs. Earth's 24 hours. Mars has a larger orbit area; therefore, one year on Mars equals 1.9 Earth years.
Mars is ½ the size of Earth, but 1/10 its mass. (Universe and Beyond, pp 24-30, 2004)
Venus, not like the Roman Goddess Venus, is comparable to Earth in size, mass and surface gravity; however, the temperature far exceeds our boiling point at 460 degrees Celsius hotter than melting lead. The atmosphere is 90% denser than Earth's and composed with mostly carbon dioxide. Since the atmosphere is so dense with carbon dioxide ,the constant volcanic activity produces additional gases enough to produce a greenhouse effect. This greenhouse cloud covering in the upper atmosphere then traps the gases and prevents the sun's infrared radiation from escaping. This makes the planet sizzling hot. The landscape is dominated with active volcanoes. The rotation of Venus is so slow that a day for Venus is equal to 59 Earth days, and the nights are equally long. The snail like rotation does not provide a magnetic field like the Earth's rotation does. (Universe and Beyond, pp 30-33, 36, 37, 2004)
Mercury, the closest to the sun, has temperatures of 400 degrees Celsius. Mercury's atmosphere is completely missing. It also has one third the Earth's gravity. Mercury is half the size of the moon. The landscape looks very much like the moon cratered by the insults of space debris. Mercury has little gravity and rotates slower than Venus. It rotates its axis three times the same time it orbits the Sun twice. One Mercury day equals 176 Earth days. (Universe and Beyond pp 38-39, 2004)
This paper showed the four scenarios astronomers consider for the Earth-Moon binary system formation. Second it showed the main points of each scenario are including modern view and why that is. The paper also concludes the atmosphere composition and characterizes, and described some of the important factors including shaping, the surface and atmospheric conditions.
References
Dickinson, T. (Ed.). (2004). "Chapter 2"
The Universe and Beyond, 4th Edition. (pg 22-23) Canada: Firefly Book, Inc.
Dickinson, T. (Ed.). (2004). " Chapter 2"
The Universe and Beyond, 4th Edition. (pg 24) Canada: Firefly Book, Inc.
Dickinson, T. (Ed.). (2004). " Chapter 2"
The Universe and Beyond, 4th Edition. (pg 36-37) Canada: Firefly Book, Inc.
Dickinson, T. (Ed.). (2004). " Chapter 2"
The Universe and Beyond, 4th Edition. (pg 24-30) Canada: Firefly Book, Inc.
Dickinson, T. (Ed.). (2004). " Chapter 2"
The Universe and Beyond, 4th Edition. (pg 30-33) Canada: Firefly Book, Inc.
Dickinson, T. (Ed.). (2004). " Chapter 2"
The Universe and Beyond, 4th Edition. (pg 36) Canada: Firefly Book, Inc.
Dickinson, T. (Ed.). (2004). " Chapter 2"
The Universe and Beyond, 4th Edition. (pg 37) Canada: Firefly Book, Inc.
Dickinson, T. (Ed.). (2004). " Chapter 2"
The Universe and Beyond, 4th Edition. (pg 38-39) Canada: Firefly Book, Inc.
Sunday, January 02, 2000
Mars
The four inner planets of our solar system exhibit different day and year durations. Based on your reading so far, how might these differences impact the possibility of sustaining life as we know it? As a result of these variations, what differences do you think would emerge in the hypothetical life forms on the four planets?
Mars may of had life about 4.5 billion years ago. The ALH 84001 meteorite suggests that Mars was 'terraformed' on some continent during this era. The ALH 84001 meteorite had polycyclic aromatic hydrocarbons that used to be microfossils. These indents are 20 to 100 nanometer. The scientists say that the PAHs weren't leaked into them. PAH are the remains of micro-organisms. Astronauts would have to put plants inside greenhouses on Mars to shield them against dust storms. Mercury and Venus wouldn't have life, because both are full of volcanic activity and are way too close to the sun. There is ice near the poles, which all came from meteorites. Maybe the micro-organisms live in the fungus which is frozen with the water. I think that day and year variations have little to do with it life as we know it, rather the distance Earth and Mars are from the Sun, how much ice or water there are, and the denser atmosphere. Mars's air pressure is too low for liquids. Mercury has a strange orbit and it's gets too close to the sun at times and one side of the planet is scorched. Plants won't survive on Mercury, because sunlight is six times brighter than ours. Mars would have to have some micro-organisms. I was thinking as far as life forms, Mercury and Venus would have to have androids working on the planets. Mars, Jupiter, Saturn, Venus could have androids working on them too. I think, the more gravity, organic life forms would be shorter and weigh more. In less gravity, organic life forms would be taller and leaner. Another life form could be a virus I refer to as "Andromeda Strain" found on these planets (under a rock) where it is extremely difficult to make an antidote. I don't agree that the Groom Lake area in Nevada is restricted, because of Mars, Mercury, Saturn, Jupiter, Neptune or Venus! Anything at Groom Lake goes beyond!
Mars may of had life about 4.5 billion years ago. The ALH 84001 meteorite suggests that Mars was 'terraformed' on some continent during this era. The ALH 84001 meteorite had polycyclic aromatic hydrocarbons that used to be microfossils. These indents are 20 to 100 nanometer. The scientists say that the PAHs weren't leaked into them. PAH are the remains of micro-organisms. Astronauts would have to put plants inside greenhouses on Mars to shield them against dust storms. Mercury and Venus wouldn't have life, because both are full of volcanic activity and are way too close to the sun. There is ice near the poles, which all came from meteorites. Maybe the micro-organisms live in the fungus which is frozen with the water. I think that day and year variations have little to do with it life as we know it, rather the distance Earth and Mars are from the Sun, how much ice or water there are, and the denser atmosphere. Mars's air pressure is too low for liquids. Mercury has a strange orbit and it's gets too close to the sun at times and one side of the planet is scorched. Plants won't survive on Mercury, because sunlight is six times brighter than ours. Mars would have to have some micro-organisms. I was thinking as far as life forms, Mercury and Venus would have to have androids working on the planets. Mars, Jupiter, Saturn, Venus could have androids working on them too. I think, the more gravity, organic life forms would be shorter and weigh more. In less gravity, organic life forms would be taller and leaner. Another life form could be a virus I refer to as "Andromeda Strain" found on these planets (under a rock) where it is extremely difficult to make an antidote. I don't agree that the Groom Lake area in Nevada is restricted, because of Mars, Mercury, Saturn, Jupiter, Neptune or Venus! Anything at Groom Lake goes beyond!
Saturday, January 01, 2000
Stars sizes
1. How would you rank the following according to their size (starting with the smallest): A galaxy, a planet, a star, solar system, a galaxy cluster. Share where you found your information.
2. Which of the objects in #1, if any, are within a 1 light-year radius from Earth? More than 1 light-year, but within 100 light-years?
3. Share one interesting fact or explanation from your readings this week that illustrates the vast size of the universe. Explain why this strikes you as interesting.
(smallest to largest) Diameter
1.) Planet (Earth) Earth's Circumference at the Equator: 24,901.55 miles (40,075.16 km); Earth's Diameter at the Poles: 7,899.80 miles (12,713.5 km); Earth's Circumference Between the North and South Poles: 24,859.82 miles (40,008 km) [1]
2.) Star (Sun) 1,392,000 KM (865,000 MI.) [1]
3.) Solar System Sun to Pluto (dwarf planet) 78.88 AU; Sun to end of Oort Cloud 100,000 AU [1] Oort cloud starts at 50,000 AU AU stands for Earth-Sun distance.
4.) Galaxy 4 billion, 8 thousand, 3 hundred, and 29 miles big or 100,000 lightyears diameter [1][2][3]
5.) local group cluster 3,000 kiloparsecs (10 million light years) diameter [1]
6.) Virgo Cluster (galaxy supercluster) 15 million light years diameter [1]
2.) All the planets or dwarf planets that don’t pass Pluto, and the Sun are all within a light year. I read the true distance of the solar system is 2 light years in distance that includes the comets that orbit the Sun. Other stars within 100 light years include Barnard’s Star, Alpha Centauri, Sirius, Procyon, Tau Ceti, Epsiton Eridani, and Tau Ceti, and 93 other stars. [Universe and Beyond, pg 13, 2004] [1: Greater Distances]
3.) It took until 2002 to upgrade Hubble’s camera to get a blurry glimpse of the first galaxies. The book says that 99% of the universe is invisible (gas and dust) full of dark matter (23%) and dark energy (73%) and 3.4% of other elements. The book also says that the distance between stars is 20 times the Pluto orbit so that’s really far apart. Stars can be as close as 10 AU each other. [Universe and Beyond, pg 99, 110, 2004] This is interesting, because when I think of light years; it took 3-4 minutes for to travel to new star systems in various Star Trek episodes going five or six times light speed per second. Also Alpha Centauri seems very close at 4.4 light years when the average distance between stars is 20 light years. [Universe and Beyond, pg 74, 2004]
Scientists use the Hubble Deep Space Field to see the Andromeda Galaxy. Astronomers reduce the size of space objects to walnuts, cherries, oranges, and peas. If Earth was a dime sized and every other space object was relevant to Earth; it would take minutes to travel to new star systems, and more than a lifetime to travel to new galaxies. The reading also says that the speed of light is 674,533,030 mph and is 5,908,909,342,800 miles total in length. I can see why traveling to other solar systems take that long, because there are billions of star systems in the Milky Way Galaxy. A billion seconds is roughly 31 years, 8 months, 8 days according to my graphical calculator so I won't have seen most of the galaxy before I die even if fictionally I travel to a new star systems every few minutes. The second example I've chosen is a rotating neutron star, also known as a pulsar. Pulsars blink at you, and are easy to discover with a telescope. Stars expel gas and radiation and astronomers can tell the composition by how fast these evaporate. (Universe and Beyond, pg 16 – 18, 2004) (Gino, 2010)
I asked myself when reading the first chapter why scientists scale down the distances to fit in the palm of your hand and using atoms, peas, ping-pong balls to visualize scaled down objects seems crude and my brain refuses to melt. I also like the conversions of light-years and Astronomical Unit (AU) into more recognizable measurements such as miles. Overall, I like the technical jargon explanations over the scaled down references. However, I have found crossing star systems every couple of minutes until traveling to another galaxy in my life time impossible.
This paper explained how astronomers read the cosmos and my personal opinion on the reasons behind it.
References
Dickinson, T. (Ed.). (2004). "A Journey Through Time and Space"
The Universe and Beyond, 4th Edition. (pg 11-19) Canada: Firefly Book, Inc.
Gino, C. (2010). Week 01 - The Universe as We Know It
Retrieved April 9, 2010, from Rasmussen website
http://rasmussen.learntoday.info/section/default.asp?id=SPR10-G239-10
2. Which of the objects in #1, if any, are within a 1 light-year radius from Earth? More than 1 light-year, but within 100 light-years?
3. Share one interesting fact or explanation from your readings this week that illustrates the vast size of the universe. Explain why this strikes you as interesting.
(smallest to largest) Diameter
1.) Planet (Earth) Earth's Circumference at the Equator: 24,901.55 miles (40,075.16 km); Earth's Diameter at the Poles: 7,899.80 miles (12,713.5 km); Earth's Circumference Between the North and South Poles: 24,859.82 miles (40,008 km) [1]
2.) Star (Sun) 1,392,000 KM (865,000 MI.) [1]
3.) Solar System Sun to Pluto (dwarf planet) 78.88 AU; Sun to end of Oort Cloud 100,000 AU [1] Oort cloud starts at 50,000 AU AU stands for Earth-Sun distance.
4.) Galaxy 4 billion, 8 thousand, 3 hundred, and 29 miles big or 100,000 lightyears diameter [1][2][3]
5.) local group cluster 3,000 kiloparsecs (10 million light years) diameter [1]
6.) Virgo Cluster (galaxy supercluster) 15 million light years diameter [1]
2.) All the planets or dwarf planets that don’t pass Pluto, and the Sun are all within a light year. I read the true distance of the solar system is 2 light years in distance that includes the comets that orbit the Sun. Other stars within 100 light years include Barnard’s Star, Alpha Centauri, Sirius, Procyon, Tau Ceti, Epsiton Eridani, and Tau Ceti, and 93 other stars. [Universe and Beyond, pg 13, 2004] [1: Greater Distances]
3.) It took until 2002 to upgrade Hubble’s camera to get a blurry glimpse of the first galaxies. The book says that 99% of the universe is invisible (gas and dust) full of dark matter (23%) and dark energy (73%) and 3.4% of other elements. The book also says that the distance between stars is 20 times the Pluto orbit so that’s really far apart. Stars can be as close as 10 AU each other. [Universe and Beyond, pg 99, 110, 2004] This is interesting, because when I think of light years; it took 3-4 minutes for to travel to new star systems in various Star Trek episodes going five or six times light speed per second. Also Alpha Centauri seems very close at 4.4 light years when the average distance between stars is 20 light years. [Universe and Beyond, pg 74, 2004]
Scientists use the Hubble Deep Space Field to see the Andromeda Galaxy. Astronomers reduce the size of space objects to walnuts, cherries, oranges, and peas. If Earth was a dime sized and every other space object was relevant to Earth; it would take minutes to travel to new star systems, and more than a lifetime to travel to new galaxies. The reading also says that the speed of light is 674,533,030 mph and is 5,908,909,342,800 miles total in length. I can see why traveling to other solar systems take that long, because there are billions of star systems in the Milky Way Galaxy. A billion seconds is roughly 31 years, 8 months, 8 days according to my graphical calculator so I won't have seen most of the galaxy before I die even if fictionally I travel to a new star systems every few minutes. The second example I've chosen is a rotating neutron star, also known as a pulsar. Pulsars blink at you, and are easy to discover with a telescope. Stars expel gas and radiation and astronomers can tell the composition by how fast these evaporate. (Universe and Beyond, pg 16 – 18, 2004) (Gino, 2010)
I asked myself when reading the first chapter why scientists scale down the distances to fit in the palm of your hand and using atoms, peas, ping-pong balls to visualize scaled down objects seems crude and my brain refuses to melt. I also like the conversions of light-years and Astronomical Unit (AU) into more recognizable measurements such as miles. Overall, I like the technical jargon explanations over the scaled down references. However, I have found crossing star systems every couple of minutes until traveling to another galaxy in my life time impossible.
This paper explained how astronomers read the cosmos and my personal opinion on the reasons behind it.
References
Dickinson, T. (Ed.). (2004). "A Journey Through Time and Space"
The Universe and Beyond, 4th Edition. (pg 11-19) Canada: Firefly Book, Inc.
Gino, C. (2010). Week 01 - The Universe as We Know It
Retrieved April 9, 2010, from Rasmussen website
http://rasmussen.learntoday.info/section/default.asp?id=SPR10-G239-10
Friday, October 22, 1999
Structure and Function of the Human Body week 10
Answer each of the questions below using information gathered from your readings, lectures, and outside research. You should provide at least a paragraph response for each of the questions.
1. Describe the role of the following organs within the digestive system: stomach, liver, salivary glands, small intestine and gallbladder. Also, describe what complications could occur within the functions of the digestive system if each listed organ was damaged or dysfunctional.
Our digestive system provides the body a means to transfer nutrition from the external environment into the cellular level in order to sustain life.
Salivary glands, controlled by the autonomic nervous system, is located in the oral cavity. It's main role is to secrete saliva in the oral cavity. There are three pairs of salivary glands. Parotoid savary gland lies under the skin on each side of the mandible. These glands secrete amylase, an enzyme that breaks down starches. The parotoid duct implies empties into the vestibile at the level of the second upper molar. The sublingual duct is (located under the tongue) between the mucus membrane of the floor of the mouth and the submandibular duct is located in the floor of the mouth. Both the sublingual and submandibular glands secrete saliva that contains more buffers and mucus. (p. 539-40)
Saliva (mucus) consists of 99.4% water, mucins and an assortments ions, buffers, and waste products and enzymes. The mucines absorbs water and form the mucus. During meal time, the saliva lubricates the mouth along with dissolved chemicals that stimulates the taste buds. The mucus coats the food, and reduces friction making swallowing easier. The continuous flow of saliva also flushes and cleans the oral surfaces while controlling oral bacteria through salivary antibodies (IgA and lysozyme). The pH of saliva during meal time raises from slightly acidic (pH 6.7) to more alkaline (pH 7.5).
Radiation and emotional distress can cause a reduction of salivary secretions. This then can create an unhealthy oral cavity environment due to increased bacteria population. Over time, the complications caused by the decreased salivary secretions are infection and erosion of the teeth and gums. (p.540)
The stomach is another component of the digestive system which is located within the left upper quadrant of the abdominal cavity. It is a muscular J-shaped organ that is positioned inferior of the esophagus and superior to the small intestines. There are four primary functions the stomach has to offer. First, it becomes a temporary storage for ingested food. Food is stored in the stomach while it is physically broken down for chemical digestion. Second, it provides a mechanical means to break down ingested food. The stomach is an area where there is a lot of mixing of the food, so added strength to the muscularis external layer is needed. Instead of two layers in the muscular external, the stomach's has three layers, a longitudinal layer, a circular layer, and an inner oblique layer. Thirdly, it provides an acidic environment that causes a break down of the chemical bonds in food through the actions of acids and enzymes. The pH of 2.0 in the stomach makes the environment acidic. The ingested foods, mixed with stomach's secretion, produces an acidic soupy mixture of partially digested food called chyme. Lastly, the stomach is responsible for the production of the intrinsic factor, a compound necessary for the absorption of vitamin B-12. (p.544)
Gastric ulcers is one complication that can occur in the stomach. Ulcers are caused either bacterium Helicobacter pylori or by medication such as aspirin that irritates the mucus membrane. This irritation causes erosion of the mucus membrane; which either creates an excessive production of acid or an inadequate production of alkaline mucus that defends the epithelium against the acid. Treatment can lean toward a medication such as cimetidine, a drug that inhibits acidity in the stomach, or it can be treated with antibiotics for bacterial infection depending on the cause. Meal time still would include a complete diet, but staying away from high fat, high acidic foods like tomatoes, and spicy foods. In atropic gastritis, there is chronic inflammation in the stomach which produces a lower acid production capability. When this happens, the intrinsic factor is affected , trapping vitamin B12 within the food. People in this case would need to take a vitamin B12 supplement.
The small intestines main function is in the digestion and absorption of nutrients. Ninety percent of nutrient absorption occurs in the small intestine. The duodenum is the segment in the small intestine that receives chyme from the stomach and digestion secretions from the pancreas. It also contains duodenal glands which secrete alkaline mucus that helps buffer acids in the chyme. The bulk of chemical digestion and nutrient absorption occurs in the jejunum. The small intestines receives and raises the pH of the materials arriving from the stomach. Most of the important digestive processes are completed in the small intestine where the final products of digestion (simple sugars, fatty acids, amino acids) are absorb along with most of the water contents. (p. 548)
Crohn's disease is one complication found in the small intestine. It is a chronic auto-immune inflammatory disorder that occurs in intervals active (flares) disease altering in periods of remission . Treatment varies from special diets, medication like Cortisone and surgery (possible ileostomy). Crohn's disease is not curable. Treatment only covers the symptoms caused by the disease progression. Over time, the inflammation of the small intestine can result in scaring and thickening of the walls of the affected structure. With this disease, absorption of nutrition can lead to difficulties. The inflammation causes damages to the lining of the intestine so that it cannot absorb nutrients, water, and fats from the food eatened. This can result in malnutrition, dehydration, vitamin and mineral deficiencies. (emedicinehealth, 2011)
The liver is an essential part to the digestive process. The liver has three functional roles: metabolic regulation, hematological, and bile production. The basic functional unit of the liver is its 100,00 lobules. Within each lobule there are liver cells called hepatocytes .
In metabolic regulation, the liver's main goal is to regulate the composition of the circulating blood. It does this through the hepatocytes. The hepatocytes extract and absorbed nutrients or toxins from the blood prior to reaching the general circulation. Hepatocytes also monitors/adjusts the circulating levels of organic nutrients. Excesses are removed and stored; while deficiencies are corrected by utilizing stored reserves or synthesizing the necessary compounds. Toxin and metabolic wastes are removes for later inactivation and excretion. Fat-cell vitamins such as A,D,K, and E are absorbed and stored. ( p.555-6)
With hematological regulation, the liver becomes the blood reservoir. As the blood passes through the liver, phagocytes (kupffer ) cells remove spent/or damaged RBCs, debris, and pathogens from the circulation. The hepatocytes synthesizes plasma proteins ( which determines blood's osmotic concentration), transports nutrients, and makeup the clotting and complement systems. ( p.556)
The bile production is derived from the hepatocyte secretions. Bile may either flow into the common bile duct, which empties into the duodenum, or enters into the cystic duct, which leads into the gallbladder. Bile consist of water, ions, bilirubin (pigment from hemoglobin), cholesterol, and bile salts (an assortment of lipids). The bile's water and ions dilute and buffer acids in chyme as it enter the small intestine. The bile salts (synthesized from cholesterol) are required for normal digestion and absorption of fats. Bile breaks down large lipid droplets into smaller lipid particles in order for the digestive enzymes to become more effective. ( p.556)
After revealing the main functions the liver provides, any condition that can damage or make the liver dysfunctional can be life threating to the body. One example is hepatitis which is an inflammation of the liver producing swelling in the liver. There are many virus that can cause hepatitis depending in how it is transmitted, but the main ones are A, B, and C. If left untreated, in some cases hepatitis can lead to cirrhosis which is a progressive degenerate disease that results in the loss of organ/tissue function due to scar tissue. Further progression of the disease could eventually lead to liver failure. Unlike a healthy liver, the liver would not be able fight infection, clean the blood and help digest food and store energy; thus, leaving the body, toxic.
The gallbladder is a hollow pear-shape organ that stores and concentrates bile made in the liver. Bile is secreted continuously (approx1 liter/day); however, it is only release into the common duct to the duodenum when fatty foods enters the digestive tract and through the stimulation of a duodenum's hormone CCK (cholecystokinin). The CCK stimulates contractions in the walls of the gallbladder, releasing the bile into the small intestine. In the absence of CCK, bile leaving the liver through the common duct is redirected into the cystic duct delivering bile into the gallbladder for storage.
The concentration of bile changes its composition while in the gallbladder's storage. Water is absorbed and the bile salts along with other bile components become increasing concentrated. Sometimes bile salts become too concentrated through stasis (due to no-fat diet) or infection which alters the ratio of bile salts and water content, forming gallstones. ( pg.550, 556-7)
Gallstones can be a complication of the gallbladder. Gallstones can develop when bile contains too much cholesterol, too much bilirubin, or not enough bile salts, or when the gallbladder does not completely empty or emptied enough. Most people are unaware they have a problem. If a person is asymptomatic, no treatment necessary. Only those with sever discomfort or repeated attacks from gallstones receive treatment. This usually requires surgery for removal of the gallbladder (cholecystectomy). People can live without their gallbladder because bile is made continuously and the gallbladder is just a reservoir for bile. If any change in life style it would be in diet (low-fat) and frequently of meals. (mayoclinic.com, ) ( p.557)
Explain how the small intestine’s anatomy is geared to increase surface area. Why is increased surface area important in the small intestine?
The length of the small intestine is approximately 20 feet long. The intestinal lining consist of transverse folds (plicae circulares) composed of multitude of finger like projections called villi.
These structures are covered with simple columnar epithelium that are covered with microvilli, in other words the epithelium looks like bristles on a hair brush. If the small intestine was smooth and simple , the total absorption area would be about 3.6 feet long. Instead, the small intestine is composed of multiple arrangement of the intestinal wall, which consist of plicae circulares layered with villi; villi is layered with epithelium; epithelium that is layered with microvilli; thus makes the total increase absorption area approximately 2,200 feet.
3. Describe the role of each of the four layers in the stomach including the mucus cells and parietal cells of the mucosa layer.
The four layers of the stomach are the mucosa layer, submucosa layer, muscularis externa, and serosa layer.
The mucosa layer of the stomach is the inner lining consisting of mucosal (glandular secreted) membrane that is composed of simple columnar epithelium dominated by mucus cells. The role of these mucus cells this is to secrete alkaline mucus that covers and protects epithelial cells from acids, enzymes, and abrasive material. Gastric pits are shallow depressions open onto the gastric surface. The mucus cells at the base of each gastric pit divide and replace the superficial cells of the mucus epithelium which is then shed into the chyme. The gastric pit corresponds with the gastric glands which secrete the gastric juice. The cells that produce the components of the gastric juice as the parietal cells. The parietal cells secrete the intrinsic factor and hydrochloric acid. The intrinsic factor is needed to facilitate the absorption of Vitamin B-12 across the intestinal lining. The hydrochloric acid lowers the pH of the gastric juices which keeps the stomach pH contents at approximately 2. The acidity of the stomach kills micro organisms, helps break down plant cell walls, and connective tissues in meat and also activates the enzyme secretions of the chief cells. The main purpose of chief cells is the production of the enzyme pepin (a protein digesting enzyme) Within both the mucosa and sub-mucus are distinct ridges or folds called rugae. The folds increase the surface area for absorption and permits expansion (flattens out) for food. Ducts between the rugae opens onto the epithelial surface and carries the gastric glands that secrete digestive juices.
The sub-mucosa layer is the second layer that is composed loose connecting tissue which contain large blood vessels, lymphatic vessels, and nerve fibers( sensory neurons and parasympathetic motor neurons). Its main role is in controlling and coordinating contraction of the smooth muscle layers and in regulating secretion.
Muscularis externa makes up the third layer of the stomach. This layer consist of bands of smooth muscle cells which contains a longitudinal layer, a circular layer, and an inner oblique layer. These three portions of the muscularis externa provides strength and assists in the mixing and churning essential to forming chyme.
The serosa layer (visceral peritoneum) covers the outer surface of the stomach. It has no role except to stabilize the stomach in the peritoneal cavity.
4. We discussed the endocrine role of the pancreas when we studied the endocrine system but it has an exocrine role within the digestive system. Please explain what type of dysfunction would occur if the pancreas didn’t secrete its pancreatic juices. What type of dysfunction would occur if someone had to have their gallbladder removed?
The pancreas is primary an exocrine organ that produces digestive buffers and enzymes. The four enzymes: carbohydrases (digest surgars and starches), lipases (break down lipids), nucleases (break down nucleic acids), and proteases (break protein apart). Specific enzymes are the pancreatic amylase (breaks down carbohydrates), pancreatic lipase (group of nucleases and several proteases), and trypsin and chymotrypsin are all part of the proteases enzymes Proteases accounts for 70% of the enzyme production. The main buffer is sodium bicarbonate which increases the pH of the chyme. (pg 552-553)
If the pancreas becomes dysfunctional, these pancreatic and enzymes would be missing in the duodemum. Inadequate digestion would take place. Your sugars, starches, fats, and proteins would be incompletely digested, because of the missing enzymes. In pancreatitis, inflammation occurs from blockage of excretory ducts, bacterial infection, or drug reaction (alcohol), This can cause injury in the exocrine cells. The lysosomes within the damaged cells then activated the pancreatic enzyme which attack the normal pancreatic cells and there is a chain reaction which produces destruction. In most cases, with treatment, this can be reversed/stopped. However, there are a few cases where this auto-digestion continues and destroys the organ. In that case, two conditions result: diabetes mellitus that requires insulin and nutrient malabsorption where oral pancreatic enzymes need to be taken. (pg 563)
In the case of the gallbladder, people can live without their gallbladder, because the only function of the gallbladder is a reservoir for bile from the liver. Bile will continue the flow into the small intestines without a problem. It might be a little more or less depending on the food quantity and substance.
5. What is the importance of adenosine triphosphate (ATP)? Carbohydrate metabolism is our body’s main source of ATP production. Explain where carbohydrate metabolism occurs in the cell, what additional “ingredient” is needed and what waste product is produced in this process.
The primary function of ATP is the transfer energy from one location to another, not the long term storage of energy. The energy a cell produces in the form of ATP supports cell growth division, contraction, secretion, and all functions that vary from cell to cell and tissue to tissue. Cells in the body generate most ATP through aerobic (oxygen-required) metabolism in the mitochondria ;however,the initial steps occur through glycolysis (anaerobic -with out oxygen) in the cystosol of the cytoplasm. Oxygen is the key ingredient needed in mitochondria energy production. Aerobic (oxygen) metabolism in the mitochondria provide most (95%) of the energy needed to keep cells alive. Most of the energy deriving from carbohydrates are produced in the mitochondria. Energy is stored and transferred in a high energy bond of ATP in order to move from place to place. The by-product of areobic metabolism is carbon dioxide. Glycolysis involves enzymatic steps that breakdown glucose to pyruvic acid molecules. These molecules are then absorbed by the mitochondria. Glycolysis (anarobic) can also continue to provide ATP when the oxygen availability is limited for mitochondrial production. This usually occurs during the body's peak activity, such in the case of a long distance runner. The body cannot provide enough O2 to maintain the metabolism in the metochondria. This the time where glycolysis becomes the prime source for ATP. (p.77, 210, 577)
References
http://www.emedicinehealth.com/crohn_disease/article_em.htm#Crohn%27s%20Disease%20Overview
http://www.mayoclinic.com/health/gallstones/DS00165/DSECTION=causeshttp://www.mayoclinic.com/health/gallstones/DS00165/DSECTION=causes
1. Describe the role of the following organs within the digestive system: stomach, liver, salivary glands, small intestine and gallbladder. Also, describe what complications could occur within the functions of the digestive system if each listed organ was damaged or dysfunctional.
Our digestive system provides the body a means to transfer nutrition from the external environment into the cellular level in order to sustain life.
Salivary glands, controlled by the autonomic nervous system, is located in the oral cavity. It's main role is to secrete saliva in the oral cavity. There are three pairs of salivary glands. Parotoid savary gland lies under the skin on each side of the mandible. These glands secrete amylase, an enzyme that breaks down starches. The parotoid duct implies empties into the vestibile at the level of the second upper molar. The sublingual duct is (located under the tongue) between the mucus membrane of the floor of the mouth and the submandibular duct is located in the floor of the mouth. Both the sublingual and submandibular glands secrete saliva that contains more buffers and mucus. (p. 539-40)
Saliva (mucus) consists of 99.4% water, mucins and an assortments ions, buffers, and waste products and enzymes. The mucines absorbs water and form the mucus. During meal time, the saliva lubricates the mouth along with dissolved chemicals that stimulates the taste buds. The mucus coats the food, and reduces friction making swallowing easier. The continuous flow of saliva also flushes and cleans the oral surfaces while controlling oral bacteria through salivary antibodies (IgA and lysozyme). The pH of saliva during meal time raises from slightly acidic (pH 6.7) to more alkaline (pH 7.5).
Radiation and emotional distress can cause a reduction of salivary secretions. This then can create an unhealthy oral cavity environment due to increased bacteria population. Over time, the complications caused by the decreased salivary secretions are infection and erosion of the teeth and gums. (p.540)
The stomach is another component of the digestive system which is located within the left upper quadrant of the abdominal cavity. It is a muscular J-shaped organ that is positioned inferior of the esophagus and superior to the small intestines. There are four primary functions the stomach has to offer. First, it becomes a temporary storage for ingested food. Food is stored in the stomach while it is physically broken down for chemical digestion. Second, it provides a mechanical means to break down ingested food. The stomach is an area where there is a lot of mixing of the food, so added strength to the muscularis external layer is needed. Instead of two layers in the muscular external, the stomach's has three layers, a longitudinal layer, a circular layer, and an inner oblique layer. Thirdly, it provides an acidic environment that causes a break down of the chemical bonds in food through the actions of acids and enzymes. The pH of 2.0 in the stomach makes the environment acidic. The ingested foods, mixed with stomach's secretion, produces an acidic soupy mixture of partially digested food called chyme. Lastly, the stomach is responsible for the production of the intrinsic factor, a compound necessary for the absorption of vitamin B-12. (p.544)
Gastric ulcers is one complication that can occur in the stomach. Ulcers are caused either bacterium Helicobacter pylori or by medication such as aspirin that irritates the mucus membrane. This irritation causes erosion of the mucus membrane; which either creates an excessive production of acid or an inadequate production of alkaline mucus that defends the epithelium against the acid. Treatment can lean toward a medication such as cimetidine, a drug that inhibits acidity in the stomach, or it can be treated with antibiotics for bacterial infection depending on the cause. Meal time still would include a complete diet, but staying away from high fat, high acidic foods like tomatoes, and spicy foods. In atropic gastritis, there is chronic inflammation in the stomach which produces a lower acid production capability. When this happens, the intrinsic factor is affected , trapping vitamin B12 within the food. People in this case would need to take a vitamin B12 supplement.
The small intestines main function is in the digestion and absorption of nutrients. Ninety percent of nutrient absorption occurs in the small intestine. The duodenum is the segment in the small intestine that receives chyme from the stomach and digestion secretions from the pancreas. It also contains duodenal glands which secrete alkaline mucus that helps buffer acids in the chyme. The bulk of chemical digestion and nutrient absorption occurs in the jejunum. The small intestines receives and raises the pH of the materials arriving from the stomach. Most of the important digestive processes are completed in the small intestine where the final products of digestion (simple sugars, fatty acids, amino acids) are absorb along with most of the water contents. (p. 548)
Crohn's disease is one complication found in the small intestine. It is a chronic auto-immune inflammatory disorder that occurs in intervals active (flares) disease altering in periods of remission . Treatment varies from special diets, medication like Cortisone and surgery (possible ileostomy). Crohn's disease is not curable. Treatment only covers the symptoms caused by the disease progression. Over time, the inflammation of the small intestine can result in scaring and thickening of the walls of the affected structure. With this disease, absorption of nutrition can lead to difficulties. The inflammation causes damages to the lining of the intestine so that it cannot absorb nutrients, water, and fats from the food eatened. This can result in malnutrition, dehydration, vitamin and mineral deficiencies. (emedicinehealth, 2011)
The liver is an essential part to the digestive process. The liver has three functional roles: metabolic regulation, hematological, and bile production. The basic functional unit of the liver is its 100,00 lobules. Within each lobule there are liver cells called hepatocytes .
In metabolic regulation, the liver's main goal is to regulate the composition of the circulating blood. It does this through the hepatocytes. The hepatocytes extract and absorbed nutrients or toxins from the blood prior to reaching the general circulation. Hepatocytes also monitors/adjusts the circulating levels of organic nutrients. Excesses are removed and stored; while deficiencies are corrected by utilizing stored reserves or synthesizing the necessary compounds. Toxin and metabolic wastes are removes for later inactivation and excretion. Fat-cell vitamins such as A,D,K, and E are absorbed and stored. ( p.555-6)
With hematological regulation, the liver becomes the blood reservoir. As the blood passes through the liver, phagocytes (kupffer ) cells remove spent/or damaged RBCs, debris, and pathogens from the circulation. The hepatocytes synthesizes plasma proteins ( which determines blood's osmotic concentration), transports nutrients, and makeup the clotting and complement systems. ( p.556)
The bile production is derived from the hepatocyte secretions. Bile may either flow into the common bile duct, which empties into the duodenum, or enters into the cystic duct, which leads into the gallbladder. Bile consist of water, ions, bilirubin (pigment from hemoglobin), cholesterol, and bile salts (an assortment of lipids). The bile's water and ions dilute and buffer acids in chyme as it enter the small intestine. The bile salts (synthesized from cholesterol) are required for normal digestion and absorption of fats. Bile breaks down large lipid droplets into smaller lipid particles in order for the digestive enzymes to become more effective. ( p.556)
After revealing the main functions the liver provides, any condition that can damage or make the liver dysfunctional can be life threating to the body. One example is hepatitis which is an inflammation of the liver producing swelling in the liver. There are many virus that can cause hepatitis depending in how it is transmitted, but the main ones are A, B, and C. If left untreated, in some cases hepatitis can lead to cirrhosis which is a progressive degenerate disease that results in the loss of organ/tissue function due to scar tissue. Further progression of the disease could eventually lead to liver failure. Unlike a healthy liver, the liver would not be able fight infection, clean the blood and help digest food and store energy; thus, leaving the body, toxic.
The gallbladder is a hollow pear-shape organ that stores and concentrates bile made in the liver. Bile is secreted continuously (approx1 liter/day); however, it is only release into the common duct to the duodenum when fatty foods enters the digestive tract and through the stimulation of a duodenum's hormone CCK (cholecystokinin). The CCK stimulates contractions in the walls of the gallbladder, releasing the bile into the small intestine. In the absence of CCK, bile leaving the liver through the common duct is redirected into the cystic duct delivering bile into the gallbladder for storage.
The concentration of bile changes its composition while in the gallbladder's storage. Water is absorbed and the bile salts along with other bile components become increasing concentrated. Sometimes bile salts become too concentrated through stasis (due to no-fat diet) or infection which alters the ratio of bile salts and water content, forming gallstones. ( pg.550, 556-7)
Gallstones can be a complication of the gallbladder. Gallstones can develop when bile contains too much cholesterol, too much bilirubin, or not enough bile salts, or when the gallbladder does not completely empty or emptied enough. Most people are unaware they have a problem. If a person is asymptomatic, no treatment necessary. Only those with sever discomfort or repeated attacks from gallstones receive treatment. This usually requires surgery for removal of the gallbladder (cholecystectomy). People can live without their gallbladder because bile is made continuously and the gallbladder is just a reservoir for bile. If any change in life style it would be in diet (low-fat) and frequently of meals. (mayoclinic.com, ) ( p.557)
Explain how the small intestine’s anatomy is geared to increase surface area. Why is increased surface area important in the small intestine?
The length of the small intestine is approximately 20 feet long. The intestinal lining consist of transverse folds (plicae circulares) composed of multitude of finger like projections called villi.
These structures are covered with simple columnar epithelium that are covered with microvilli, in other words the epithelium looks like bristles on a hair brush. If the small intestine was smooth and simple , the total absorption area would be about 3.6 feet long. Instead, the small intestine is composed of multiple arrangement of the intestinal wall, which consist of plicae circulares layered with villi; villi is layered with epithelium; epithelium that is layered with microvilli; thus makes the total increase absorption area approximately 2,200 feet.
3. Describe the role of each of the four layers in the stomach including the mucus cells and parietal cells of the mucosa layer.
The four layers of the stomach are the mucosa layer, submucosa layer, muscularis externa, and serosa layer.
The mucosa layer of the stomach is the inner lining consisting of mucosal (glandular secreted) membrane that is composed of simple columnar epithelium dominated by mucus cells. The role of these mucus cells this is to secrete alkaline mucus that covers and protects epithelial cells from acids, enzymes, and abrasive material. Gastric pits are shallow depressions open onto the gastric surface. The mucus cells at the base of each gastric pit divide and replace the superficial cells of the mucus epithelium which is then shed into the chyme. The gastric pit corresponds with the gastric glands which secrete the gastric juice. The cells that produce the components of the gastric juice as the parietal cells. The parietal cells secrete the intrinsic factor and hydrochloric acid. The intrinsic factor is needed to facilitate the absorption of Vitamin B-12 across the intestinal lining. The hydrochloric acid lowers the pH of the gastric juices which keeps the stomach pH contents at approximately 2. The acidity of the stomach kills micro organisms, helps break down plant cell walls, and connective tissues in meat and also activates the enzyme secretions of the chief cells. The main purpose of chief cells is the production of the enzyme pepin (a protein digesting enzyme) Within both the mucosa and sub-mucus are distinct ridges or folds called rugae. The folds increase the surface area for absorption and permits expansion (flattens out) for food. Ducts between the rugae opens onto the epithelial surface and carries the gastric glands that secrete digestive juices.
The sub-mucosa layer is the second layer that is composed loose connecting tissue which contain large blood vessels, lymphatic vessels, and nerve fibers( sensory neurons and parasympathetic motor neurons). Its main role is in controlling and coordinating contraction of the smooth muscle layers and in regulating secretion.
Muscularis externa makes up the third layer of the stomach. This layer consist of bands of smooth muscle cells which contains a longitudinal layer, a circular layer, and an inner oblique layer. These three portions of the muscularis externa provides strength and assists in the mixing and churning essential to forming chyme.
The serosa layer (visceral peritoneum) covers the outer surface of the stomach. It has no role except to stabilize the stomach in the peritoneal cavity.
4. We discussed the endocrine role of the pancreas when we studied the endocrine system but it has an exocrine role within the digestive system. Please explain what type of dysfunction would occur if the pancreas didn’t secrete its pancreatic juices. What type of dysfunction would occur if someone had to have their gallbladder removed?
The pancreas is primary an exocrine organ that produces digestive buffers and enzymes. The four enzymes: carbohydrases (digest surgars and starches), lipases (break down lipids), nucleases (break down nucleic acids), and proteases (break protein apart). Specific enzymes are the pancreatic amylase (breaks down carbohydrates), pancreatic lipase (group of nucleases and several proteases), and trypsin and chymotrypsin are all part of the proteases enzymes Proteases accounts for 70% of the enzyme production. The main buffer is sodium bicarbonate which increases the pH of the chyme. (pg 552-553)
If the pancreas becomes dysfunctional, these pancreatic and enzymes would be missing in the duodemum. Inadequate digestion would take place. Your sugars, starches, fats, and proteins would be incompletely digested, because of the missing enzymes. In pancreatitis, inflammation occurs from blockage of excretory ducts, bacterial infection, or drug reaction (alcohol), This can cause injury in the exocrine cells. The lysosomes within the damaged cells then activated the pancreatic enzyme which attack the normal pancreatic cells and there is a chain reaction which produces destruction. In most cases, with treatment, this can be reversed/stopped. However, there are a few cases where this auto-digestion continues and destroys the organ. In that case, two conditions result: diabetes mellitus that requires insulin and nutrient malabsorption where oral pancreatic enzymes need to be taken. (pg 563)
In the case of the gallbladder, people can live without their gallbladder, because the only function of the gallbladder is a reservoir for bile from the liver. Bile will continue the flow into the small intestines without a problem. It might be a little more or less depending on the food quantity and substance.
5. What is the importance of adenosine triphosphate (ATP)? Carbohydrate metabolism is our body’s main source of ATP production. Explain where carbohydrate metabolism occurs in the cell, what additional “ingredient” is needed and what waste product is produced in this process.
The primary function of ATP is the transfer energy from one location to another, not the long term storage of energy. The energy a cell produces in the form of ATP supports cell growth division, contraction, secretion, and all functions that vary from cell to cell and tissue to tissue. Cells in the body generate most ATP through aerobic (oxygen-required) metabolism in the mitochondria ;however,the initial steps occur through glycolysis (anaerobic -with out oxygen) in the cystosol of the cytoplasm. Oxygen is the key ingredient needed in mitochondria energy production. Aerobic (oxygen) metabolism in the mitochondria provide most (95%) of the energy needed to keep cells alive. Most of the energy deriving from carbohydrates are produced in the mitochondria. Energy is stored and transferred in a high energy bond of ATP in order to move from place to place. The by-product of areobic metabolism is carbon dioxide. Glycolysis involves enzymatic steps that breakdown glucose to pyruvic acid molecules. These molecules are then absorbed by the mitochondria. Glycolysis (anarobic) can also continue to provide ATP when the oxygen availability is limited for mitochondrial production. This usually occurs during the body's peak activity, such in the case of a long distance runner. The body cannot provide enough O2 to maintain the metabolism in the metochondria. This the time where glycolysis becomes the prime source for ATP. (p.77, 210, 577)
References
http://www.emedicinehealth.com/crohn_disease/article_em.htm#Crohn%27s%20Disease%20Overview
http://www.mayoclinic.com/health/gallstones/DS00165/DSECTION=causeshttp://www.mayoclinic.com/health/gallstones/DS00165/DSECTION=causes
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