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anotherworld2b

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Human biology questions
« on: July 04, 2016, 12:27:45 pm »
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Hi I was wondering if I could get help in answering some questions :)
I've attempted at answering them but I'm unsure whether I am right particularly for Q2.

* Q1
Absorption of nutrients depends on concentration differences so that substances diffuse across the absorbing surface. Explain how the concentration difference is maintained in the parts of the alimentary canal where absorption occurs.

Concentration difference is maintained in the small intestine which consists of millions of lacteals.  In the small intestine there is high surface area which allows for greater absorption.  Which will be absorbed into either lymph or blood vessels. In the lacteals there is active and passive transport of materials. Monosaccharides, amino acids, water soluble vitamins undergo active transport into blood. Osmosis involves the passive transport of water into blood. Lastly, diffusion of fat soluble vitamins and fatty acids and glycerol into lacteal. Concentration difference is maintained through the movement of lacteal in the villi in the small intestine.

* Q2
In doing the wall sit in Activity 11.2, your quadriceps muscle was contracting isometrically. Muscles are also to contract isotonically. Find out the difference between these two types of muscle contraction. Then, using the biceps muscles as an example, describe situations that would result in each of these two types of contraction.
« Last Edit: July 06, 2016, 03:25:19 pm by anotherworld2b »

Skidous

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Re: Human biology questions
« Reply #1 on: July 14, 2016, 03:39:52 pm »
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Hi anotherworld2b,
So far the responses that were given were pretty good, depending on the length of the question (judging by the marks) this is a good start. To improve the answer though to ensure you can get as many marks as possible, try and be more specific with your answer.
Here's some feed back I'd give for your first answer
Concentration difference is maintained in the small intestine which consists of millions of lacteals.  In the small intestine there is high surface area which allows for greater absorption This is a good way to explain the absorption of digestive products but you need to be clearer as to WHY this is. So if you explain that the folding of these lacteals allows for a larger surface area to volume ratio (SA:V) within the small intestines allowing for more efficient absorption of nutrients the answer would be better .  Which will be absorbed into either lymph or blood vessels This should be one sentence . In the lacteals there is active and passive transport of materials. Monosaccharides, amino acids, water soluble vitamins undergo active transport into blood. Osmosis involves the passive transport of water into blood. Lastly, diffusion of fat soluble vitamins and fatty acids and glycerol into lacteal Whilst it is good to mention osmosis as a form of passive transport, you also have to state 2 things. 1: Osmosis must occur through a semi-permeable membrane and 2: It occurs in the large intestines mostly . Concentration difference is maintained through the movement of lacteal in the villi in the small intestine. Whilst 'movement' could suffice in answering this question in order to maintain this difference, you should be mentioning the CONSTANT movement of concentrations in order to keep the difference. Also you need to mention that the movement for passive transport is along the concentration gradient, as well as the fact that active transport is against the concentration gradient and requires energy in the form of ATP

For question 2, I'm not quite sure how I would go about asking this question since it seems to be more of a PDHPE question. It might be beneficial to try and post this 2nd question on the PDHPE  forum here: Personal Development, Health and Physical Education

Hope this helps you with your questions

Skidous
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CinnamonTea

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Re: Human biology questions
« Reply #2 on: July 17, 2016, 12:38:58 am »
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The second question is related to pdhpe

vox nihili

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Re: Human biology questions
« Reply #3 on: July 17, 2016, 10:50:32 am »
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Hi I was wondering if I could get help in answering some questions :)
I've attempted at answering them but I'm unsure whether I am right particularly for Q2.

* Q1
Absorption of nutrients depends on concentration differences so that substances diffuse across the absorbing surface. Explain how the concentration difference is maintained in the parts of the alimentary canal where absorption occurs.

Concentration difference is maintained in the small intestine which consists of millions of lacteals.  In the small intestine there is high surface area which allows for greater absorption.  Which will be absorbed into either lymph or blood vessels. In the lacteals there is active and passive transport of materials. Monosaccharides, amino acids, water soluble vitamins undergo active transport into blood. Osmosis involves the passive transport of water into blood. Lastly, diffusion of fat soluble vitamins and fatty acids and glycerol into lacteal. Concentration difference is maintained through the movement of lacteal in the villi in the small intestine.

* Q2
In doing the wall sit in Activity 11.2, your quadriceps muscle was contracting isometrically. Muscles are also to contract isotonically. Find out the difference between these two types of muscle contraction. Then, using the biceps muscles as an example, describe situations that would result in each of these two types of contraction.

You could also probably give the second question a look online. There's a lot of stuff about how muscles work on YouTube that are pretty good.
Basics though iso=same, metric=length, tonic=tone.

So in the case of biceps:

isometric: let's say someone asks you to put your arms out and passes you a brick. Your arms stay put, but obviously your biceps has to contract to carry the weight of the brick. So it's isometric because the muscle length hasn't changed, but not isotonic because the tone of biceps has increased so as to carry the weight

I'll give you a chance to work out an example of isotonic
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anotherworld2b

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Re: Human biology questions
« Reply #4 on: July 17, 2016, 07:44:58 pm »
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Would this be a better answer? Would it be necessary to mention other parts of the alimentary canal? I
 
Q1. Absorption of nutrients depends on concentration differences so that substances diffuse across the absorbing surface. Explain how the concentration difference is maintained in the parts of the alimentary canal where absorption occurs.

Concentration difference is maintained in the small intestine which consists of millions of lacteals. Inside the villus is a lymph capillary, called a lacteal, which is surrounded by a network of blood capillaries.The structure of a villus is ideally suited to its function of nutrient absorption. Each villus is about 1mm long and is covered by a single layer of cells.  In the small intestine there is high surface area which allows for greater absorption into either lymph or blood vessels. This is due to the folding of lacteals allowing for a larger surface area to volume ratio (SA:V) within the small intestines allowing for more efficient absorption of nutrients.

In the lacteals there is active and passive transport of materials. Monosaccharides, amino acids, water soluble vitamins undergo active transport into blood. Osmosis involves the passive transport of water into blood.Osmosis must occur through a semipermeable membrane and mainly occurs in the large intestines. Concentration difference is maintained through the constant movement of concentrations of lacteal in the villi in the small intestine. The concentration difference is also maintained by the diffusion of fat soluble vitamins and fatty acids and glycerol into lacteal. The movement for passive transport is along the concentration gradient, as well as the fact that active transport is against the concentration gradient and requires energy in the form of ATP.

Absorption is further enhanced by continual movement of the villi brought about by the muscular movements of the intestinal wall. This constantly brings the villi into contact with different parts of the intestinal contents, These contents are constantly changing as new material is emptied into the small intestine from the stomach.

I've tried to answer this question as well?

Q1. In doing the wall sit in Activity 11.2, your quadriceps muscle was contracting isometrically. Muscles are also to contract isotonically. Find out the difference between these two types of muscle contraction. Then, using the biceps muscles as an example, describe situations that would result in each of these two types of contraction.

Isometric contractions is when muscle shortens and movement occurs. Whereas, Isotonic contractions is when muscle does not shorten but tension increases.

Types of Muscle Contraction. An isotonic concentric contraction results in the muscle shortening, an isotonic eccentric contraction results in the muscle lengthening. During an isometric contraction the muscle is under tension but neither shortens, nor lengthens.

One example of a situation where these two types of contractions occur is when you lift a weight/dumbbell.

Isotonic: lifting a dumbell?
Isometric: tension(increase of workload) applied while joint and muscle remains in the same position. Eg. holding a cup and filling it with water. Eg. yoga.

I've also tried to answer this question but I'm not sure whether my assumption is right

Q3. The desert hopping mouse lives on dry seeds and never drinks water. It has extremely long kidney tubules.
From where does the desert hopping, mouse get its water? (refer to chap 6)


Even through the desert hopping mouse lives on only dry seeds the glucose it extracts from its food will inevitably produce water as a byproduct.The desert hopping mouse gets its water as a byproduct of cellular respiration by using the dry seeds it ingests as a source of energy. This enables the desert hopping mouse to get water through cellular respiration.

The equation for respiration:

C6H12O6 + 6O2 6CO2 + 6H2O

Glucose + Oxygen  Carbon dioxide + water

How is the desert hopping mouse able to reduce water loss in urine to a minimum?
The desert hopping mouse can reduce water loss in urine to a minimum through its extremely long kidney tubules. These tubules will filter and absorb as much water as possible. The long kidney tubules of the desert hopping mouse is significantly more efficient when compared to human kidney tubules.

Another question:
Q4. At one time. It was believed that disease was caused by ‘bad blood’. Taking large amounts of blood from a patient by bleeding (blood-letting) was widely practised as a cure for disease. Louis XII of France had blood taken 47 times in six months; Louis XV was bled 38 times, and Charles XII of England had blood taken numerous times, even just before his death. Describe some of the effects that the removal of large quantities of blood would have on a patient.

Blood-letting was a common practise in medical history which involved the removal of some of a patient's blood for therapeutic purposes to heal ailments. Some effects of the removal of large quantities of blood on a patient include: weariness and dizziness due to anaemia, fall in blood pressure, people may be tired, short of breath, and pale. These effects occur because due to the removal of large quantities of blood, blood pressure falls because the amount of fluid left in the blood vessels is insufficient. The body’s oxygen supply is drastically reduced because the number of oxygen-carrying red blood cells has decreased so quickly.

If there is extreme blood loss the effects on the patient could be life threatening such as hypovolemic shock or Hemorrhagic Shock.

vox nihili

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Re: Human biology questions
« Reply #5 on: July 17, 2016, 09:19:33 pm »
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Would this be a better answer? Would it be necessary to mention other parts of the alimentary canal? I
 
Q1. Absorption of nutrients depends on concentration differences so that substances diffuse across the absorbing surface. Explain how the concentration difference is maintained in the parts of the alimentary canal where absorption occurs.

Concentration difference is maintained in the small intestine which consists of millions of lacteals. Inside the villus is a lymph capillary, called a lacteal, which is surrounded by a network of blood capillaries.The structure of a villus is ideally suited to its function of nutrient absorption. Each villus is about 1mm long and is covered by a single layer of cells.  In the small intestine there is high surface area which allows for greater absorption into either lymph or blood vessels. This is due to the folding of lacteals allowing for a larger surface area to volume ratio (SA:V) within the small intestines allowing for more efficient absorption of nutrients.

In the lacteals there is active and passive transport of materials. Monosaccharides, amino acids, water soluble vitamins undergo active transport into blood. Osmosis involves the passive transport of water into blood.Osmosis must occur through a semipermeable [...]

yep, lifting a dumbbell is right :)
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Skidous

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Re: Human biology questions
« Reply #6 on: July 19, 2016, 04:20:37 pm »
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Would this be a better answer? Would it be necessary to mention other parts of the alimentary canal? I
 
Q1. Absorption of nutrients depends on concentration differences so that substances diffuse across the absorbing surface. Explain how the concentration difference is maintained in the parts of the alimentary canal where absorption occurs.

Concentration difference is maintained in the small intestine which consists of millions of lacteals. Inside the villus is a lymph capillary, called a lacteal, which is surrounded by a network of blood capillaries.The structure of a villus is ideally suited to its function of nutrient absorption. Each villus is about 1mm long and is covered by a single layer of cells.  In the small intestine there is high surface area which allows for greater absorption into either lymph or blood vessels. This is due to the folding of lacteals allowing for a larger surface area to volume ratio (SA:V) within the small intestines allowing for more efficient absorption of nutrients.

In the lacteals there is active and passive transport of materials. Monosaccharides, amino acids, water soluble vitamins undergo active transport into blood. Osmosis involves the passive transport of water into blood.Osmosis must occur through a semipermeable membrane and mainly occurs in the large intestines. Concentration difference is maintained through the constant movement of concentrations of lacteal in the villi in the small intestine. The concentration difference is also maintained by the diffusion of fat soluble vitamins and fatty acids and glycerol into lacteal. The movement for passive transport is along the concentration gradient, as well as the fact that active transport is against the concentration gradient and requires energy in the form of ATP.

Absorption is further enhanced by continual movement of the villi brought about by the muscular movements of the intestinal wall. This constantly brings the villi into contact with different parts of the intestinal contents, These contents are constantly changing as new material is emptied into the small intestine from the stomach.

I've tried to answer this question as well?

Q1. In doing the wall sit in Activity 11.2, your quadriceps muscle was contracting isometrically. Muscles are also to contract isotonically. Find out the difference between these two types of muscle contraction. Then, using the biceps muscles as an example, describe situations that would result in each of these two types of contraction.

Isometric contractions is when muscle shortens and movement occurs. Whereas, Isotonic contractions is when muscle does not shorten but tension increases.

Types of Muscle Contraction. An isotonic concentric contraction results in the muscle shortening, an isotonic eccentric contraction results in the muscle lengthening. During an isometric contraction the muscle is under tension but neither shortens, nor lengthens.

One example of a situation where these two types of contractions occur is when you lift a weight/dumbbell.

Isotonic: lifting a dumbell?
Isometric: tension(increase of workload) applied while joint and muscle remains in the same position. Eg. holding a cup and filling it with water. Eg. yoga.

I've also tried to answer this question but I'm not sure whether my assumption is right

Q3. The desert hopping mouse lives on dry seeds and never drinks water. It has extremely long kidney tubules.
From where does the desert hopping, mouse get its water? (refer to chap 6)


Even through the desert hopping mouse lives on only dry seeds the glucose it extracts from its food will inevitably produce water as a byproduct.The desert hopping mouse gets its water as a byproduct of cellular respiration by using the dry seeds it ingests as a source of energy. This enables the desert hopping mouse to get water through cellular respiration.

The equation for respiration:

C6H12O6 + 6O2 6CO2 + 6H2O

Glucose + Oxygen  Carbon dioxide + water

How is the desert hopping mouse able to reduce water loss in urine to a minimum?
The desert hopping mouse can reduce water loss in urine to a minimum through its extremely long kidney tubules. These tubules will filter and absorb as much water as possible. The long kidney tubules of the desert hopping mouse is significantly more efficient when compared to human kidney tubules.

Another question:
Q4. At one time. It was believed that disease was caused by ‘bad blood’. Taking large amounts of blood from a patient by bleeding (blood-letting) was widely practised as a cure for disease. Louis XII of France had blood taken 47 times in six months; Louis XV was bled 38 times, and Charles XII of England had blood taken numerous times, even just before his death. Describe some of the effects that the removal of large quantities of blood would have on a patient.

Blood-letting was a common practise in medical history which involved the removal of some of a patient's blood for therapeutic purposes to heal ailments. Some effects of the removal of large quantities of blood on a patient include: weariness and dizziness due to anaemia, fall in blood pressure, people may be tired, short of breath, and pale. These effects occur because due to the removal of large quantities of blood, blood pressure falls because the amount of fluid left in the blood vessels is insufficient. The body’s oxygen supply is drastically reduced because the number of oxygen-carrying red blood cells has decreased so quickly.

If there is extreme blood loss the effects on the patient could be life threatening such as hypovolemic shock or Hemorrhagic Shock.

Hey anotherworld2b
Q1 was a very good edit, much better than your first attempt, but you still need to talk about how active transport requires energy to perform the function. You also need to refer to concentration gradients and how the nutrients move along these gradients (passive WITH the gradient, active AGAINST)

For Q3 your equation for respiration is incorrect as it is
C6H12O6 + 6O2 --> 6CO2 + 6H2O + ATP (Heat)
This is because if ATP is left out the chemical equation is not correct as respiration is the breakdown of glucose and oxygen to produce energy for metabolic functions.
Q4
You should not only refer to the improved absorption of water due to the longer tubules, you need to reference the increased concentration of the urea in the urine as well as the minimal excretion of urine to preserve as much water as possible.
Q5
You do not need to refer to tiredness if you say it causes weariness, you need to talk about what anemia is, but overall the question is good.
Hope this helps
Skidous
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anotherworld2b

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Re: Human biology questions
« Reply #7 on: July 20, 2016, 11:03:06 pm »
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Hey anotherworld2b
Q1 was a very good edit, much better than your first attempt, but you still need to talk about how active transport requires energy to perform the function. You also need to refer to concentration gradients and how the nutrients move along these gradients (passive WITH the gradient, active AGAINST)

For Q3 your equation for respiration is incorrect as it is
C6H12O6 + 6O2 --> 6CO2 + 6H2O + ATP (Heat)
This is because if ATP is left out the chemical equation is not correct as respiration is the breakdown of glucose and oxygen to produce energy for metabolic functions.
Q4
You should not only refer to the improved absorption of water due to the longer tubules, you need to reference the increased concentration of the urea in the urine as well as the minimal excretion of urine to preserve as much water as possible.
Q5
You do not need to refer to tiredness if you say it causes weariness, you need to talk about what anemia is, but overall the question is good.
Hope this helps
Skidous

Thank you so much for your feedback :D
For the active transport requiring energy to perform the function. Would you talk about ATP conversions?
'You also need to refer to concentration gradients and how the nutrients move along these gradients (passive WITH the gradient, active AGAINST)' In regards to this particular aspect I am kind of confused how it works. I know to an extent that fat is passive so it has low gradient? into the lacteal -> lymph?

It is greatly appreciated

Skidous

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Re: Human biology questions
« Reply #8 on: July 22, 2016, 04:38:41 pm »
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Hey anotherworld2b
Concentration gradients refer to moving from a higher concentration to a lower one (think of the hypotenuse of a right angle triangle, the highest part is higher concentration then lowest end is lower concentration). So for Passive transport the nutrients move along that concentration gradient (High to Low) whereas Active Transport uses ATP to go AGAINST this gradient (low concentration to high). This also occurs for movement of nitrogenous waste out of cells.
As for the ATP conversion you don't really need to refer to that, just as long as you recognize that ATP is used in active transport.
Also you have to specify where the concentration for the fat or other nutrients is high or low (From a high concentration in the lacteal to a lower concentration in the lymph)
Hope that helps out
Skidous
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anotherworld2b

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Re: Human biology questions
« Reply #9 on: July 22, 2016, 09:02:11 pm »
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Hey anotherworld2b
Concentration gradients refer to moving from a higher concentration to a lower one (think of the hypotenuse of a right angle triangle, the highest part is higher concentration then lowest end is lower concentration). So for Passive transport the nutrients move along that concentration gradient (High to Low) whereas Active Transport uses ATP to go AGAINST this gradient (low concentration to high). This also occurs for movement of nitrogenous waste out of cells.
As for the ATP conversion you don't really need to refer to that, just as long as you recognize that ATP is used in active transport.
Also you have to specify where the concentration for the fat or other nutrients is high or low (From a high concentration in the lacteal to a lower concentration in the lymph)
Hope that helps out
Skidous

thank you so much for your help :D
I was wondering could the concentration be maintained by blood as well?
I heard that it could but would it be relevant for how the concentration difference is maintained in the parts of the alimentary canal where absorption occurs? How would this work?

Skidous

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Re: Human biology questions
« Reply #10 on: July 22, 2016, 10:08:52 pm »
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Hi anotherworld2b

Yes it would be good to talk about how blood maintains the concentration difference. This is because since the blood is constantly flowing towards or away from organs, nutrients is always being absorbed into the blood stream or into the organs. In the case of the alimentary canal, the blood flowing past the canal in the capillaries will maintain the concentration difference as new blood is always being passed by the canal, promoting the transport of nutrients via diffusion and osmosis (or active transport) into the blood so that it can be taken into other parts of the body.

Hope this helps out
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vox nihili

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Re: Human biology questions
« Reply #11 on: July 22, 2016, 10:12:04 pm »
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Hi anotherworld2b

Yes it would be good to talk about how blood maintains the concentration difference. This is because since the blood is constantly flowing towards or away from organs, nutrients is always being absorbed into the blood stream or into the organs. In the case of the alimentary canal, the blood flowing past the canal in the capillaries will maintain the concentration difference as new blood is always being passed by the canal, promoting the transport of nutrients via diffusion and osmosis (or active transport) into the blood so that it can be taken into other parts of the body.

Hope this helps out
Skidous

Just to add to this.

Such is the bloody flow around the alimentary canal (called the portal system btw), all the stuff that diffuses into the blood is taken away straight away, such that the concentration of the blood remains effectively constant.
You'll see this is a fairly common theme in biology. It's the movement of blood through the lungs that maintains the concentration gradient for oxygen, through the kidneys that allows urine to be concentrated etc etc.
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anotherworld2b

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Re: Human biology questions
« Reply #12 on: July 23, 2016, 01:28:10 am »
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Just to add to this.

Such is the bloody flow around the alimentary canal (called the portal system btw), all the stuff that diffuses into the blood is taken away straight away, such that the concentration of the blood remains effectively constant.
You'll see this is a fairly common theme in biology. It's the movement of blood through the lungs that maintains the concentration gradient for oxygen, through the kidneys that allows urine to be concentrated etc etc.

I've tried to rewrite my response would this be better? All feedback is appreciated :D

Q1. Absorption of nutrients depends on concentration differences so that substances diffuse across the absorbing surface. Explain how the concentration difference is maintained in the parts of the alimentary canal where absorption occurs.

Concentration difference is maintained in the small intestine which consists of millions of lacteals. Inside the villus is a lymph capillary, called a lacteal, which is surrounded by a network of blood capillaries.The structure of a villus is ideally suited to its function of nutrient absorption. In the small intestine there is high surface area which allows for greater absorption into either lymph or blood vessels. This is due to the folding of lacteals allowing for a larger surface area to volume ratio (SA:V) within the small intestines allowing for more efficient absorption of nutrients.

In the lacteals there is active and passive transport of materials. Monosaccharides, amino acids, water soluble vitamins undergo active transport into the blood. This is due to using ATP to go against the high concentration of these materials in the blood vessel from the low concentration in the lacteal.

Osmosis involves the passive transport of water into blood.Osmosis must occur through a semipermeable membrane and mainly occurs in the large intestines. Concentration difference is maintained through the constant movement of concentrations of lacteal in the villi in the small intestine. The concentration difference is also maintained by the diffusion of fat soluble vitamins and fatty acids and glycerol into lacteal through passive transport from high concentration in the lacteal to a lower concentration in the lymph, The movement for passive transport is along the concentration gradient, as well as the fact that active transport is against the concentration gradient and requires energy in the form of ATP.

The muscular movements of the intestinal wall constantly brings the villi into contact with different parts of the intestinal contents, These contents are constantly changing as new material is emptied into the small intestine from the stomach. The constant influx of nutrients from the consumption of food ensures that the concentration gradient is maintained as nutrients are diffused from the small intestines into the lacteal. This diffusion occurs due to the high concentration of nutrients in the small intestines diffusion into the lacteal with a low concentration of these nutrients. These nutrients that are diffused into the lacteal are then travel in lymph vesicles to lymph nodes. This ensures that a low concentration of these nutrients is maintained in the villi of the small intestines.

Blood is part of the circulatory system which maintains the concentration difference of substances in the alimentary canal. Blood is constantly circulated towards and away from organs allowing nutrients to be absorbed into organs and waste to be collected from the blood stream. In regards to the alimentary canal new blood is always being passed by the canal in the capillaries allowing the transport of nutrients through diffusion, osmosis and active transport into the blood. This is maintains the concentration of nutrients by the fact that the material diffused into the blood is circulated away and around the body allowing diffusion to occurring constantly retaining a constant concentration of the blood.

Skidous

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Re: Human biology questions
« Reply #13 on: July 23, 2016, 02:31:15 pm »
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I've tried to rewrite my response would this be better? All feedback is appreciated :D

Q1. Absorption of nutrients depends on concentration differences so that substances diffuse across the absorbing surface. Explain how the concentration difference is maintained in the parts of the alimentary canal where absorption occurs.

Concentration difference is maintained in the small intestine which consists of millions of lacteals. Inside the villus is a lymph capillary, called a lacteal, which is surrounded by a network of blood capillaries.The structure of a villus is ideally suited to its function of nutrient absorption. In the small intestine there is high surface area which allows for greater absorption into either lymph or blood vessels. This is due to the folding of lacteals allowing for a larger surface area to volume ratio (SA:V) within the small intestines allowing for more efficient absorption of nutrients.

In the lacteals there is active and passive transport of materials. Monosaccharides, amino acids, water soluble vitamins undergo active transport into the blood. This is due to using ATP to go against the high concentration of these materials in the blood vessel from the low concentration in the lacteal.

Osmosis involves the passive transport of water into blood.Osmosis must occur through a semipermeable membrane and mainly occurs in the large intestines. Concentration difference is maintained through the constant movement of concentrations of lacteal in the villi in the small intestine. The concentration difference is also maintained by the diffusion of fat soluble vitamins and fatty acids and glycerol into lacteal through passive transport from high concentration in the lacteal to a lower concentration in the lymph, The movement for passive transport is along the concentration gradient, as well as the fact that active transport is against the concentration gradient and requires energy in the form of ATP.

The muscular movements of the intestinal wall constantly brings the villi into contact with different parts of the intestinal contents, These contents are constantly changing as new material is emptied into the small intestine from the stomach. The constant influx of nutrients from the consumption of food ensures that the concentration gradient is maintained as nutrients are diffused from the small intestines into the lacteal. This diffusion occurs due to the high concentration of nutrients in the small intestines diffusion into the lacteal with a low concentration of these nutrients. These nutrients that are diffused into the lacteal are then travel in lymph vesicles to lymph nodes. This ensures that a low concentration of these nutrients is maintained in the villi of the small intestines.

Blood is part of the circulatory system which maintains the concentration difference of substances in the alimentary canal. Blood is constantly circulated towards and away from organs allowing nutrients to be absorbed into organs and waste to be collected from the blood stream. In regards to the alimentary canal new blood is always being passed by the canal in the capillaries allowing the transport of nutrients through diffusion, osmosis and active transport into the blood. This is maintains the concentration of nutrients by the fact that the material diffused into the blood is circulated away and around the body allowing diffusion to occurring constantly retaining a constant concentration of the blood.

Hey AnotherworldB

This response is MUCH better since the last response, however I do notice that you've done some copy-paste of the information that's been given by both myself and Mr T-Rave. Whilst that is good for the information, it isn't as good in responses if they aren't modified to make the sentences run smoothly. If the sentences don't run smoothly, it may place your response from full marks to just under full marks because it was not as cohesive and coherent as a full mark response should be.

To better this response, it is not about the information but your structure. Depending on the marks allocated to this question, the structure may differ.

If it is a 3-4 mark question, you need to immediately go onto the answer, and be concise with your information and get straight to the point. Unlike English, waffling in Bio will make it seem like you don't understand what is being asked. You should also make distinct arguments in your response, so if you want to talk about passive transport, make 2-3 sentence about passive transport only and then say something along the lines of "Active transport is also used..." and continue with active transport. Ensure that the information your given also links to the question.

5-6 Mark Question require a little more information but the structure is very similar (These are usually Assess or Discuss questions so cause and effect language will be needed and a judgment will be needed [but only for the assess question])

7-8 Mark Questions require planning on the structure and understanding where your information must go and being discerning with what information is relevant and what is not. Sometimes it may be better to draw a table, for this you must remember to use headings and draw a box around the table otherwise you will lose marks (I'm not kidding).

Since this appears to be a 3-4 mark question (since it is explain) I want you to try and condense the information as there is far too much for a 3-4 marker in the HSC or Trials

So try to answer this one without copy-paste from your previous response or the information given here

Explain how the differences in nutrient concentrations ensures that absorption will occurs in the alimentary canal. 4-Marks
ATAR: 93

English (Advanced): 88
Mathematics: 81
Biology: 91
Physics: 85
Chemistry: 82
Studies of Religion (2 Unit): 88

Most of my knowledge lies in Bio so ask me anything on that

anotherworld2b

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Re: Human biology questions
« Reply #14 on: July 23, 2016, 09:54:20 pm »
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I will rewrite my response following your advice:D
I just wanted to put all the information I've received in one place before I lose track of what to include :)
I really appreciate all the help I've received :D