Turn on thread page Beta
    • Thread Starter
    Offline

    2
    ReputationRep:
    Starting the unofficial biology unit 3 mark scheme. This is for the AQA GCSE New Specification test which everyone did on the 14th May 2013.

    ________________________________ ________________________________ ________________________________

    Here is the actual exam paper: http://login.ekab.co.uk/AQA-BL3HP-QP-JUN13.pdf


    Downloadable copy here: http://www.filedropper.com/b3-june2013
    ________________________________ ________________________________ ________________________________

    Here is the mark scheme:

    Question 1 [12]

    [4]

    1. Coronary Artery [1]
    2. Stents [1]
    3. Stents are metal mesh tubes inserted into blood vessels to expand them if they are blocked, for example by fatty deposits or cholesterol. They are placed in surgery using an inflated balloon. It increases the blood vessel size at the blockage to allow blood to flow more effectively. [2]


    OR

    1. Coronary Artery [1]
    2. Coronary Bypass Surgery [1]
    3. The heart is stopped in surgery. The narrowed section of coronary artery is cut and removed from the surface of the heart. Then, another section of blood vessel, usually from the groin, is cut out and the two ends of the vessel stitched back up. The section of vessel is then taken to the location on the heart and stitched onto the coronary artery. The heart is restarted and the blood should effectively. [2]
      .
    4. Artery [1]
      Capillary [1]
      Vein [1]
      .
    5. The blood in the artery is de-oxygenated (without oxygen) while the blood in the vein is oxygenated (with oxygen). [1]


    Question 2 [10]

    1. There is a slow increase in lung volume in the first 1.2 seconds. The volume peaks at 4.8 cubic dm. Then, there is a slow gradual decrease in pressure for the next 1.2 seconds. [3]
    2. When breathing in, the following occurs: the intercostal muscles contract, the ribcage expands, the diaphragm flattens, volume of thorax increases, pressure of thorax decreases and air is drawn in. This is shown by the increase and peak in the graph. The opposite is true (intercostal muscles relax and ribcage contracts) when breathing out, shown by the decrease in the graph. [3]
    3. Positive pressure ventilation systems force air into the lung, changing the pressure inside the lung. While, negative pressure systems change the pressure outside the lung, forcing air in and out. [2]
    4. An advantage of the positive pressure ventilator is that it does not interrupt the air flow in the lungs whereas in negative pressure it does. Positive pressure systems can, also, be digitally controlled and aid in muscle building. A disadvantage of positive pressure is that the alveoli can burst if it cannot handle the pressure. This can happen in small children or babies. [2]


    Question 3 [8]

    1. The second food chain (wheat→pigs→humans) has more steps and wastes more energy because the pigs use energy in respiration for movement, homoeostasis, etc. The first food chain (wheat→human) provides ten times more energy than the second food chain. [2]
      .
    2. Factory farming is when food production is made more efficient by reducing energy loss and maximising growth.

      Animals are kept in a small space or cage which reduces land requirements. This provides more space for other crops or resources and, so, more food is produced in a smaller space. This is more profitable and creates a larger yield or more produce. However, it is easier for animals to catch diseases off one another and it is expensive to monitor diseases.

      Animals' movement is, also, restricted. This reduces energy loss by movement and creates full-size animals quickly. This is more profitable and creates a larger yield or more produce. However, it is seen as cruel, unethical and inhumane as it restricts the animals' freedom- against animal rights. Moreover, stressed animals gain weight less quickly then non-stressed animals.

      Moreover, animals are kept warm and indoors. Therefore, less energy is expended by the animal on heating itself, homoeostasis. More energy is used for growth. This quickens the growing process and more profit in the long-term. But, it can be expensive to heat the animals and causes an indirect CO2 increase as fuels are burnt to produce heat energy. [6]


    Question 4 [11]

    1. (310-210)/(180-30) = 2/3 = 0.6 (Recurring) [2]
    2. Between 0-30 seconds, there was an increased rate of evaporation causing a higher water loss while between 30-180 seconds the rate of evaporation steadily decreased causing a lower water loss- this altered the rate of transpiration between the two time periods. The rate of evaporation may have altered due to change in the environment, closing of stomata or some other factor. [2]
    3. Osmosis is used by roots as there is a higher concentration of water in soil than in root, uptake is along the concentration gradient. Active transport is used as there is a higher concentration of ions in roots than in the soil, uptake is against the concentration gradient. [4]
    4. The transpiration stream is the flow of water from the root to the leaves through the xylem. It is due to water loss in the leaves, leading to low concentration of water in the leaves and high concentration of water in the roots. [3]


    Question 5 [5]

    1. Oxygen [1] Allow Mineral Ions
    2. Surface X allows exchange of food and gas which is difficult in complex organisms. As the tadpole grows, Surface X increases in surface area. This increases the surface area:volume ratio of the tadpole. Therefore, there is more area from diffusion to occur. It, also, means that gases, such as oxygen, and other dissolved substances, such as mineral ions, can diffuse in and out quickly which is important for the tadpole to survive. [4]


    Question 6 [7]

    1. When the body get too hot, the blood vessels dilate (vasodilation) to reduce body temperature and lose more heat. When the body gets too cold, the blood vessels contract (vasoconstriction) to increase body temperature and reduce heat loss. [4]
    2. The athlete overheats as there is reduced or no evaporation of sweat, which occurs slowest in humid conditions. This is due to reduced gradient or saturation or high water content of the (humid) air. Also, there is less heat loss by the (latent) heat of evaporation [3]


    Question 7 [7]

    1. The person has just had a meal. Therefore, the hepatic portal vein has contains a high level of blood sugar. Insulin is produced by the pancreas and this converts the glucose into glycogen, which is stored in the liver. Therefore, the hepatic vein contains less glucose and has a lower blood sugar level. [3]
    2. The hepatic portal vein has contains a low level of blood sugar. The body requires a constant level of blood sugar. Glycogen is produced to convert glycogen, stored in the liver, into glucose. Therefore, the hepatic vein contains more glucose than the hepatic portal vein and has a higher blood sugar level. [3]
    3. The graph decreased as transpiration in the plant stopped since the leaf had no roots for the uptake of water. Therefore, no more water was taken in by the leaf for photosynthesis. [1]



    ________________________________ ________________________________ ________________________________

    Here are the unofficial grade boundaries:

    A* : 46
    A : 37
    B : 26
    C : 17
    D : Less than 7
    Offline

    8
    ReputationRep:
    i think the answer for the marathon runner was:
    I wrote because the weather was humid the sweat couldn't evaporate and carry away the heat. So when the blood vessels dilated the heat got trapped in the sweat causing the person to overheat.
    Offline

    3
    ReputationRep:
    There is a start to the mark scheme on the other thread, you could use that.

    Posted from TSR Mobile
    Offline

    1
    ReputationRep:
    Do you remember the questions and their order? I remember most of my answers but not the questions/their wording/their positions, so I'll just throw in answers I remember.

    1) (don't remember the order) - top left, vena cava. Top right, Aorta. Bottom left, right atrium. Bottom right, right ventricle.

    The one about stents - It was in the coronary artery. Obviously the first part was "stent". Second part was something to the effect of "Stents are mesh-like tubes inserted into blood vessels to expand them if they are blocked, for example by fatty deposits or cholesterol. It increases the lumen size at the blockage to allow blood to flow more effectively.

    The tadpole one - It exchanged oxygen with the water as well. Structure X was an exchange surface I believe, as it increased the surface area of the tadpole.

    The athlete's overheating in humid conditions - when it is humid there is a higher concentration of water vapour in the air. This means the concentration gradient is shallower, and so it is harder for the water to evaporate from the skin and therefore harder for it to cool the skin by sweating, so he overheats.

    The calculation question - 310-210/180-30=0.67

    The one about the lungs - Artery, Capillary, Vein. Difference in composition is the blood in the first blood vessel (the pulmonary artery) is deoxygenated, while the blood in the second blood vessel (the pulmonary vein) is oxygenated.

    I'll add more as I remember.
    • Thread Starter
    Offline

    2
    ReputationRep:
    (Original post by pinkgorilla)
    There is a start to the mark scheme on the other thread, you could use that.

    Posted from TSR Mobile
    I couldn't find it. Can you link it? Thanks.
    Offline

    3
    ReputationRep:
    (Original post by Quantaˌ)
    I couldn't find it. Can you link it? Thanks.
    Dont think I can. I am using my phone.

    Posted from TSR Mobile
    Offline

    8
    ReputationRep:
    (Original post by shan2097)
    Do you remember the questions and their order? I remember most of my answers but not the questions/their wording/their positions, so I'll just throw in answers I remember.

    1) (don't remember the order) - top left, vena cava. Top right, Aorta. Bottom left, right atrium. Bottom right, right ventricle.

    The one about stents - It was in the coronary artery. Obviously the first part was "stent". Second part was something to the effect of "Stents are mesh-like tubes inserted into blood vessels to expand them if they are blocked, for example by fatty deposits or cholesterol. It increases the lumen size at the blockage to allow blood to flow more effectively.

    The tadpole one - It exchanged oxygen with the water as well. Structure X was an exchange surface I believe, as it increased the surface area of the tadpole.

    The athlete's overheating in humid conditions - when it is humid there is a higher concentration of water vapour in the air. This means the concentration gradient is shallower, and so it is harder for the water to evaporate from the skin and therefore harder for it to cool the skin by sweating, so he overheats.

    The calculation question - 310-210/180-30=0.67

    The one about the lungs - Artery, Capillary, Vein. Difference in composition is the blood in the first blood vessel (the pulmonary artery) is deoxygenated, while the blood in the second blood vessel (the pulmonary vein) is oxygenated.

    I'll add more as I remember.
    For the first one it was actually left ventricle
    Offline

    1
    ReputationRep:
    The six marker:

    Point - Keeping the animals cramped in a small space.
    Advantage - More space is available for other crops or resources, more food is produced in a smaller space.
    Disadvantage - Easier for animals to catch diseases off one another
    ^^ This isn't a very good one, and not in the syllabus.

    Point - Animals' movement is restricted.
    Advantage - Less energy is expended on moving around so more can be used for growth.
    Disadvantage - Seen as cruel and inhumane as it restricts the animals' freedom.

    Point - Animals are kept warm and indoors.
    Advantage - Less energy is expended by the animal on heating itself, so more can be used for growth.
    Disadvantage - Can be expensive to heat the animals, possible indirect CO2 increase as fuels are burnt to produce the heat energy.
    Offline

    1
    ReputationRep:
    (Original post by Kat187)
    For the first one it was actually left ventricle
    Oh, ok!
    Offline

    3
    ReputationRep:
    The question about the concentration of glucose in the portal veins leading to the liver being lower than the veins leading to the rest of (body?).

    The answer I wrote was because blood sugars were too low the pancreas secreted glucagon to release and break down the stored glycogen in the liver so therefore the blood going into the liver was going to absorb glucose and the vein leading out of the liver had already had glucose absorbed
    Offline

    0
    ReputationRep:
    (Original post by shan2097)
    Do you remember the questions and their order? I remember most of my answers but not the questions/their wording/their positions, so I'll just throw in answers I remember.

    1) (don't remember the order) - top left, vena cava. Top right, Aorta. Bottom left, right atrium. Bottom right, right ventricle.

    The one about stents - It was in the coronary artery. Obviously the first part was "stent". Second part was something to the effect of "Stents are mesh-like tubes inserted into blood vessels to expand them if they are blocked, for example by fatty deposits or cholesterol. It increases the lumen size at the blockage to allow blood to flow more effectively.

    The tadpole one - It exchanged oxygen with the water as well. Structure X was an exchange surface I believe, as it increased the surface area of the tadpole.

    The athlete's overheating in humid conditions - when it is humid there is a higher concentration of water vapour in the air. This means the concentration gradient is shallower, and so it is harder for the water to evaporate from the skin and therefore harder for it to cool the skin by sweating, so he overheats.

    The calculation question - 310-210/180-30=0.67

    The one about the lungs - Artery, Capillary, Vein. Difference in composition is the blood in the first blood vessel (the pulmonary artery) is deoxygenated, while the blood in the second blood vessel (the pulmonary vein) is oxygenated.

    I'll add more as I remember.
    also, it was pulmonary artery not right ventricle
    Offline

    2
    ReputationRep:
    thank you
    Offline

    4
    ReputationRep:
    (Original post by CaSeSeNsItIvE)
    also, it was pulmonary artery not right ventricle
    Im sure it was the right ventricle:confused::confused::confused: ( going on this thread makes me think i made more mistakes than i thought i had at the time lol)
    Offline

    10
    ReputationRep:
    That diagram is wrong loool first of all Arteries don't carry blood to the heart. Just switch over Aorta and Vena Cava then it's correct
    Offline

    8
    ReputationRep:
    (Original post by CaSeSeNsItIvE)
    also, it was pulmonary artery not right ventricle
    No the bottom left chamber is a ventricle. the top label was aorta no
    • Thread Starter
    Offline

    2
    ReputationRep:
    (Original post by Kamakazi145)
    Aorta and Vena Cava should be swapped in the diagram.
    Can't believe that was wrong. Sorry I was trying to multitask between this, revision and researching...
    Offline

    1
    ReputationRep:
    (Original post by shan2097)

    The athlete's overheating in humid conditions - when it is humid there is a higher concentration of water vapour in the air. This means the concentration gradient is shallower, and so it is harder for the water to evaporate from the skin and therefore harder for it to cool the skin by sweating,

    The one about the lungs - Artery, Capillary, Vein. Difference in composition is the blood in the first blood vessel (the pulmonary artery) is deoxygenated, while the blood in the second blood vessel (the pulmonary vein) is oxygenated.

    I'll add more as I remember.
    For the athlete question, I don't think concentration gradient has anything to do with it. I think it's more evaporation occurs fastest in hot, DRY, windy conditions, and therefore if its humid it will occur slower. Concentration gradient is referring to diffusion/osmosis.

    I thought the difference in composition between the arteries and veins were the properties themselves, not what type of blood they carry. I.e arteries have a smaller lumen and thick elastic wall to compensate for carrying blood at high pressures, and veins have a larger lumen to maintain a high level of blood flow dispite low blood pressure.
    • Thread Starter
    Offline

    2
    ReputationRep:
    (Original post by Masr97)
    I thought the difference in composition between the arteries and veins were the properties themselves, not what type of blood they carry. I.e arteries have a smaller lumen and thick elastic wall to compensate for carrying blood at high pressures, and veins have a larger lumen to maintain a high level of blood flow dispite low blood pressure.
    No, the question was referring to the composition of the blood. So, it's about being oxygenated or not.

    Can anyone remember what Question 3 was?
    Offline

    3
    ReputationRep:
    (Original post by Masr97)
    For the athlete question, I don't think concentration gradient has anything to do with it. I think it's more evaporation occurs fastest in hot, DRY, windy conditions, and therefore if its humid it will occur slower. Concentration gradient is referring to diffusion/osmosis.

    I thought the difference in composition between the arteries and veins were the properties themselves, not what type of blood they carry. I.e arteries have a smaller lumen and thick elastic wall to compensate for carrying blood at high pressures, and veins have a larger lumen to maintain a high level of blood flow dispite low blood pressure.
    the composition is asking what it has in it, deoxy blood and oxy blood was right otherwise it wouldnt have been a 2 mark Q
    Offline

    0
    ReputationRep:
    (Original post by Masr97)
    For the athlete question, I don't think concentration gradient has anything to do with it. I think it's more evaporation occurs fastest in hot, DRY, windy conditions, and therefore if its humid it will occur slower. Concentration gradient is referring to diffusion/osmosis.

    I thought the difference in composition between the arteries and veins were the properties themselves, not what type of blood they carry. I.e arteries have a smaller lumen and thick elastic wall to compensate for carrying blood at high pressures, and veins have a larger lumen to maintain a high level of blood flow dispite low blood pressure.
    im pretty sure they said blood composition
 
 
 
Reply
Submit reply
Turn on thread page Beta
Updated: August 16, 2013

University open days

  • University of Lincoln
    Mini Open Day at the Brayford Campus Undergraduate
    Wed, 19 Dec '18
  • University of East Anglia
    UEA Mini Open Day Undergraduate
    Fri, 4 Jan '19
  • Bournemouth University
    Undergraduate Mini Open Day Undergraduate
    Wed, 9 Jan '19
Poll
Did you get less than your required grades and still get into university?

The Student Room, Get Revising and Marked by Teachers are trading names of The Student Room Group Ltd.

Register Number: 04666380 (England and Wales), VAT No. 806 8067 22 Registered Office: International House, Queens Road, Brighton, BN1 3XE

Write a reply...
Reply
Hide
Reputation gems: You get these gems as you gain rep from other members for making good contributions and giving helpful advice.