Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Biology Exam Questions > 3 Organisms exchange substances with their environment EQs > Flashcards

3 Organisms exchange substances with their environment EQs Flashcards

You may prefer our related Brainscape-certified flashcards:
AP® Biology flashcards Biology 101 flashcards
1
Q

How is the pressure in the ventricle related to the thickness of the ventricle wall? (2 marks)

A
  1. Thickness of wall increases because ventricle wall contracts
  2. Contraction causes the increase in pressure
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

The hydrostatic pressure falls from the arteriole end of the capillary to the venule end of the capillary. Explain why. (1 mark)

A

Loss of water

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

High blood pressure leads to an accumulation of tissue fluid. Explain how. (3 marks)

A
  1. High blood pressure = high hydrostatic pressure
  2. Increases outward pressure from arterial end of capillary
  3. So more tissue fluid formed
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

The water potential of the blood plasma is more negative at the venule end of the capillary than at the arteriole end of the capillary. Explain why. (3 marks)

A
  1. Water has left the capillary;
  2. Proteins in blood too large to leave capillary;
  3. Higher concentration of blood proteins and so water potential
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

A principle of homeostasis is the maintenance of a constant internal environment. An increase in the concentration of carbon dioxide would change the internal environment and blood pH.
Explain the importance of maintaining a constant blood pH. (3 marks)

A
  1. Haemoglobin affected by change in pH
  2. Change of tertiary structure;
  3. Increases dissociation
    e.g. less oxygen binds with haemoglobin
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Although the speed of blood flow in an arteriole is greater than speed of blood flow in a capillary, blood does not accumulate in the arterioles.
Explain why. (1 mark)

A
  1. More capillaries than arterioles
  2. Cross-sectional area of capillaries much greater than of arterioles
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Other than causing slow blood flow, explain one advantage of capillaries being narrow. (2 marks)

A
  1. Short distance between blood and outside of capillary
  2. Fast exchange
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What factor limits the minimum internal diameter of the lumen of a capillary? (1 mark)

A

Size of blood cell.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

The volume of blood leaving the capillary network into the veins is less than the volume of blood entering from the arteries.
Explain why. (1 mark)

A

Fluid in tissue fluid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is the function of the coronary arteries? (2 marks)

A
  1. Carry oxygen
  2. To heart muscle
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

The rise and fall in blood pressure in the aorta is greater than in the small arteries. Suggest why. (3 mark)

A
  1. Aorta is directly linked to the heart
  2. Aorta has elastic tissue;
  3. Aorta has stretch / recoil.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

The scientists used the percentage change in the mean resting heart rate after the
exercise programme to compare the results for males and females.
Explain why they used percentage change in the resting heart rate. (2 marks)

A
  1. Allows comparison
  2. Initial heart rates different between males and females
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Explain how their cardiac output could stay the same even when their resting heart
rate had decreased in an exercise programme? (2 marks)

A
  1. Cardiac output = stroke volume × heart rate
  2. So stroke volume increases
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Give the pathway a red blood cell takes when travelling in the human circulatory system from a kidney to the lungs. (3 marks)

A
  1. Renal vein;
  2. Vena cava to right atrium;
  3. Right ventricle to pulmonary artery;
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Tissue fluid is formed from blood at the arteriole end of a capillary bed. Explain how water from tissue fluid is returned to the circulatory system. ( 4 marks)

A
  1. Plasma proteins remain;
  2. Creates water potential gradient
  3. Water moves to blood by osmosis;
  4. Returns to blood by lymphatic system;
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Explain how an arteriole can reduce the blood flow into capillaries. (2 marks)

A
  1. Muscle contracts;
  2. Narrows lumen;
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What blood vessel carries blood at the lowest
blood pressure? (1 mark)

A

Vena Cava

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

The pressure in the left ventricle is increasing.
At this time, the rate of blood flow has not yet started to increase in the aorta. Explain why (2 marks)

A
  1. Semi-lunar valves is closed;
  2. Because pressure in aorta higher than in ventricle;
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

There is a small increase in pressure and in rate of blood flow in the aorta.
Explain how this happens and its importance. (2 marks)

A
  1. Elastic recoil of the aorta wall
  2. Maintains rate of blood flow
    Maintains blood pressure
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

EPO is another performance-enhancing drug. It can increase the haematocrit (the percentage of red blood cells in blood). A heart attack is caused by a lack of glucose and oxygen being delivered to cardiac muscle via the coronary arteries. The overuse of EPO can increase the risk of a heart attack.
Suggest how. (2 marks)

A
  1. EPO causes blood to thicken;
  2. The thickened blood could block the coronary arteries
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Describe and explain the effect of increasing carbon dioxide concentration
on the dissociation of oxyhaemoglobin. (2 marks)

A
  1. More oxygen dissociation
  2. By decreasing blood pH
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Give two safety precautions that should be followed when dissecting a
heart. (1 mark)

A
  1. Wash hands/wear gloves
  2. Disinfect bench/equipment
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Explain how left atrioventricular valve maintains a unidirectional flow of blood. (2 marks)

A
  1. Pressure in left atrium is higher than in ventricle causing valve to open;
  2. Pressure in left ventricle is higher than in atrium causing valve to close;
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Explain the role of the heart in the formation of tissue fluid. (2 marks)

A
  1. Contraction of ventricle produces high hydrostatic pressure;
  2. This forces water out of blood capillaries
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Lymphoedema is a swelling in the legs which may be caused by a blockage in the lymphatic system.
Suggest how a blockage in the lymphatic system could cause
lymphoedema. (1 mark)

A

Excess tissue fluid builds up

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Why is putting a replacement organ in an isotonic solution important? (2 marks)

A
  1. Because same water potential;
  2. So prevents loss or gain of water by osmosis
  3. So cells aren’t damaged;
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Why is putting a replacement organ in an antibiotic important? (1 mark)

A

Kills bacteria that could cause infection/disease

28
Q

Describe the mass flow hypothesis for the mechanism of translocation in plants. (4 marks)

A
  1. In source sugars actively transported into phloem;
  2. By companion cells;
  3. Lowers water potential of sieve cell and water enters by osmosis;
  4. Increase in pressure causes mass movement towards sink
  5. Sugars used in root for respiration for storage.
29
Q

What other information is required in order to calculate the mean rate of movement down a trunk of a tree? (1 mark)

A

Length of trunk

30
Q

Describe how a high pressure is produced in the leaves. (3 marks)

A
  1. Water potential becomes lower as sugar enters phloem
  2. Water enters phloem by osmosis
  3. Increased volume of water causes increased pressure.
31
Q

Suggest and explain one other way in which sieve cells are
adapted for mass transport. (2 marks)

A
  1. Few organelles
  2. So more flow
32
Q

Suggest and explain one other way in which companion
cells are adapted for the transport of sugars between cells. (2 marks)

A
  1. Mitochondria release energy
  2. For active transport
33
Q

The mass flow hypothesis is used to explain the movement of substances through phloem.
Use your understanding of the mass flow hypothesis to explain how pressure is generated inside this phloem tube. (3 marks)

A
  1. Sucrose actively transported into phloem
  2. Lowering water potential
  3. Water moves into phloem by osmosis from xylem
34
Q

Phloem pressure is reduced during the hottest part of the day. Use your understanding of
transpiration and mass flow to explain why. (3 marks)

A
  1. High rate of transpiration/evaporation;
  2. Water lost through stomata
  3. Causes less water movement from xylem to phloem
35
Q

Suggest how a plant is able to survive without xylem tissue. (1 mark)

A

It has a surface permeable to water

36
Q

The student wanted to determine the rate of water loss per mm2 of surface area of the leaves of a shoot. Outline a method she could have used to find this rate. You should assume that all water loss from the shoot is from the leaves. (3 marks)

A
  1. Method for measuring area;
    e.g. draw round each leaf on graph paper and count squares;
  2. Of both sides of each leaf;
  3. Divide rate by total surface area of leaves
37
Q

The rate of water movement through a shoot in a potometer may not be the same as the rate of water movement through the shoot of a whole plant.
Suggest one reason why. (1 mark)

A

Plant has roots

38
Q

Describe the mechanism for the absorption of amino acids in the ileum (4 marks)

A
  1. Co-transport;
  2. Sodium ions actively transported from cell to blood
  3. Creating sodium ion concentration gradient;
  4. Facilitated diffusion of amino acid into blood
39
Q

High concentration of salt can lead to a build-up of tissue fluid.
Explain how. (2 marks)

A
  1. Higher salt results in lower water potential of
    tissue fluid
  2. So less water returns to capillary by osmosis at venule end
40
Q

Suggest one advantage to a bacterium secreting a protein (2 marks)

A
  1. To digest protein;
  2. So they can absorb amino acids for growth
41
Q

Describe the action of membrane-bound dipeptidases and explain their importance. (2 marks)

A
  1. Hydrolyse peptide bonds to release amino acids;
  2. Amino acids can cross cell membrane and dipeptidases cannot
42
Q

Explain three ways in which an insect’s tracheal system is adapted for efficient gas
exchange. (3 marks)

A
  1. Tracheoles have thin walls so short diffusion distance to cells
  2. Highly branched tracheoles so short diffusion distance to
    cells;
  3. Body can be moved by muscles to move air so maintains concentration gradient
43
Q

Why are gills useful for actively seeking prey underwater? (2 marks)

A
  1. higher respiratory rate
  2. so uses more oxygen
44
Q

In large cells of U. marinum, most mitochondria are found close to the cell-surface membrane. Mitochondria use oxygen during aerobic
respiration. Suggest an explanation for the position of mitochondria in large U.
marinum cells. (2 marks)

A
  1. Larger cells have smaller surface area to volume ratio;
  2. Takes longer for oxygen to diffuse to mitochondria
45
Q

Explain the advantage for larger animals of having a specialised system that facilitates oxygen uptake. (2 marks)

A
  1. Larger cells have smaller surface area to volume ratio;
  2. Faster diffusion
46
Q

Mammals such as a mouse and a horse are able to maintain a constant body temperature.
Use your knowledge of surface area to volume ratio to explain the higher metabolic rate of a mouse compared to a horse. (3 marks)

A
  1. Smaller so larger surface area to volume ratio;
  2. More heat loss per gram
  3. Faster rate of respiration/metabolism releases heat;
47
Q

Suggest one practical advantage of measuring the masses of frog eggs,
tadpoles and adults, compared with measuring their volumes. (1 mark)

A

More accurate

48
Q

Explain why oxygen uptake is a measure of metabolic rate in organisms. (1 mark)

A

Oxygen is used in respiration, which is a metabolic process

49
Q

Describe and explain one feature of the alveolar epithelium that makes the
epithelium well adapted as a surface for gas exchange. (2 marks)

A
  1. Single layer of cells
  2. Reduces diffusion distance
50
Q

Suggest and explain how a reduced tidal volume affects the exchange of
carbon dioxide between the blood and the alveoli. (3 marks)

A
  1. Less carbon dioxide exhaled
  2. So reduced diffusion (between blood and alveoli);
  3. Less movement of carbon dioxide out of blood
51
Q

Describe and explain the mechanism that causes lungs to fill with air. (3 marks)

A
  1. Diaphragm muscle contracts and external intercostal muscles
    contract;
  2. Causes volume increase and pressure decrease;
  3. Air moves down a pressure gradient
52
Q

Explain why death of alveolar epithelium cells reduces gas exchange in
human lungs. (3 marks)

A
  1. Reduced surface area;
  2. Increased distance for diffusion;
  3. Reduced rate of gas exchange;
53
Q

Suggest and explain one way the leaf growth of xerophytic plants would be
different from the leaf growth of sunflowers (2 marks)

A
  1. Low growth;
  2. Due to smaller number of stomata for gas exchange
54
Q

Explain why plants
grown in soil with very little water grow only slowly. (2 marks)

A
  1. Stomata close;
  2. Less carbon dioxide uptake for less photosynthesis
55
Q

Describe the pathway taken by an oxygen molecule from an alveolus to the blood. (2 marks)

A
  1. Across alveolar epithelium;
  2. Endothelium / epithelium of capillary;
56
Q

Explain how one feature of an alveolus allows efficient gas exchange to occur. (2 marks)

A
  1. The alveolar epithelium is one cell thick
  2. Creating a short diffusion pathway
57
Q

A student correctly plotted the right ventricle pressure on the same grid as the left ventricle pressure. Explain one way they would be similar and different. (2 marks)

A
  1. Peaks at same time
  2. Lower pressure;
58
Q

Explain how changes in the shape of haemoglobin result in the S-shaped oxyhaemoglobin dissociation curve (2 marks)

A
  1. First oxygen binds to haemoglobin causing change in shape
  2. Shape change of Hb allows more O2 to bind easier
59
Q

Give three measurements to calculate rate of water movement? (3 marks)

A
  1. Initial and final mass
  2. Number of xylem vessels
  3. Time taken for water movement
60
Q

Explain why water moves up the stalks of plants? (3 marks)

A
  1. Water evaporates from leaves
  2. Lowers water potential and creates tension
  3. Hydrogen bonds create tension
61
Q

Describe how to handle a scalpel safely during this procedure. (2 marks)

A
  1. Cut away from body
  2. Against flat surface
62
Q

Describe the role of micelles in the absorption of fats into the cells lining the ileum. (3 marks)

A
  1. Micelles include bile salts and fatty acids
  2. Make the fatty acids more soluble in water
  3. Carries fatty acids to the lining of the ileum
  4. Maintain higher concentration of fatty acids to the lining of the ileum
  5. Fatty acids absorbed by diffusion;
63
Q

Describe one way this uncontrolled cell division changes the gills (3 marks)

A
  1. thicker filament =
  2. increase diffusion distance,
  3. so gas exchange would slow down
64
Q

Give two differences between circulation of blood in fish and circulation of blood in a mammal (2 marks)

A
  1. single circulatory system in fish, double in mammal
  2. 2 chambers in fish, 4 chambers in mammal
65
Q
A

Biology Exam Questions (5 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions