OCR A Level Biology A H420/01 Biological processes JUNE 2024 merged Question Paper and Marking Scheme
Oxford Cambridge and RSA
INSTRUCTIONS
• Use black ink. You can use an HB pencil, but only for graphs and diagrams.
• Write your answer to each question in the space provided. If you need extra space use
the lined pages at the end of this booklet. The question numbers must be clearly shown.
• Answer all the questions.
• Where appropriate, your answer should be supported with working. Marks might be
given for using a correct method, even if your answer is wrong.
INFORMATION
• The total mark for this paper is 100.
• The marks for each question are shown in brackets [ ].
• Quality of extended response will be assessed in questions marked with an asterisk (*).
• This document has 36 pages.
ADVICE
• Read each question carefully before you start your answer.
© OCR 2024 [601/4260/1]
DC (SK/SG) 330031/7
OCR is an exempt Charity
Turn over
, 2
Section A
You should spend a maximum of 20 minutes on this section.
Write your answer to each question in the box provided.
1 Which statement about lipids is correct?
A Lipids are polar molecules.
B Lipids that contain fatty acids with carbon–carbon double bonds are liquid at room temperature.
C Saturated fatty acids, which are present in some lipids, contain carbon–carbon double bonds.
D The presence of carbon–carbon double bonds in fatty acids allows lipids to pack more closely
together.
Your answer [1]
2 Lipids, polysaccharides, nucleic acids and proteins are all macromolecules.
Which statement about macromolecules is correct?
A All macromolecules are formed in hydrolysis reactions.
B Lipids are not polymers, but polysaccharides, nucleic acids and proteins are polymers.
C Lipids are polymers of fatty acids and glycerol.
D Macromolecules all consist of repeating units of monomers.
Your answer [1]
3 The diagram shows part of a plasma membrane.
X
How can molecule X be described?
A It has a hydrophilic head and a hydrophobic tail.
B It is formed when the glycerol in a triglyceride is replaced by a phosphate.
© OCR 2024
, 3
C It is non-polar.
D The tails are joined to the head by peptide bonds.
Your answer [1]
4 Which statement describes a feature of plasma membranes?
A Channel proteins are a type of intrinsic protein.
B Glycolipids are intrinsic proteins that have lipid molecules attached.
C Phospholipids form a rigid bilayer that membrane proteins are attached to.
D The plasma membrane forms an impermeable barrier.
Your answer [1]
5 The adrenaline receptor is one of a class of receptors known as GPCRs. The glucagon receptor
on liver cells is another type of GPCR.
Glucagon stimulates conversion of glycogen to glucose in liver cells.
What is the action of glucagon?
A Cyclic AMP catalyses the conversion of glycogen to glucose.
B Glucagon is a second messenger.
C The glucagon receptor is located in the cytoplasm of liver cells.
D When glucagon binds to its receptor it stimulates the conversion of ATP to cyclic AMP.
Your answer [1]
6 Lymph and tissue fluid are both formed from the blood.
Which statement describes the composition of these fluids?
A Lymph contains more protein than tissue fluid because of antibody production.
B Lymph is similar in composition to tissue fluid but has more oxygen and nutrients.
C Tissue fluid does not contain hormones such as insulin and glucagon.
D Tissue fluid contains red blood cells and platelets.
© OCR 2024 Turn over
, 4
Your answer [1]
7 Which statement describes features of the mammalian heart?
A Branches of the pulmonary artery supply blood to the heart muscle.
B Semi-lunar valves prevent backflow of blood from the ventricles to the atria.
C The left ventricle pumps deoxygenated blood to the lungs.
D The wall of the left ventricle is thicker because it needs to pump blood around the whole body.
Your answer [1]
8 Bumblebees are large insects that have a high demand for oxygen during flight.
What adaptation enables bumblebees to obtain sufficient oxygen during flight?
A Accumulation of lactate in muscles during flight increases the amount of tracheal fluid which
increases the surface area for gas exchange.
B Muscle contraction before or during flight increases ventilation of the tracheal system.
C Spiracles take air directly to the respiring tissues.
D Tracheoles can open and close to allow gas exchange and minimise water loss.
Your answer [1]
9 Which option is not an adaptation that helps fish increase the efficiency of gas exchange?
A Blood capillaries lie close to the surface of the lamellae to minimise the diffusion distance.
B Blood flows in the capillaries in the same direction as the flow of water over the lamellae to
maximise gas exchange.
C Gill filaments have many lamellae that increase the surface area for gas exchange.
D Raising and lowering of the floor of the buccal cavity helps maintain a flow of water over the
gills.
Your answer [1]
10 The diagram shows part of a liver lobule.
© OCR 2024
Oxford Cambridge and RSA
INSTRUCTIONS
• Use black ink. You can use an HB pencil, but only for graphs and diagrams.
• Write your answer to each question in the space provided. If you need extra space use
the lined pages at the end of this booklet. The question numbers must be clearly shown.
• Answer all the questions.
• Where appropriate, your answer should be supported with working. Marks might be
given for using a correct method, even if your answer is wrong.
INFORMATION
• The total mark for this paper is 100.
• The marks for each question are shown in brackets [ ].
• Quality of extended response will be assessed in questions marked with an asterisk (*).
• This document has 36 pages.
ADVICE
• Read each question carefully before you start your answer.
© OCR 2024 [601/4260/1]
DC (SK/SG) 330031/7
OCR is an exempt Charity
Turn over
, 2
Section A
You should spend a maximum of 20 minutes on this section.
Write your answer to each question in the box provided.
1 Which statement about lipids is correct?
A Lipids are polar molecules.
B Lipids that contain fatty acids with carbon–carbon double bonds are liquid at room temperature.
C Saturated fatty acids, which are present in some lipids, contain carbon–carbon double bonds.
D The presence of carbon–carbon double bonds in fatty acids allows lipids to pack more closely
together.
Your answer [1]
2 Lipids, polysaccharides, nucleic acids and proteins are all macromolecules.
Which statement about macromolecules is correct?
A All macromolecules are formed in hydrolysis reactions.
B Lipids are not polymers, but polysaccharides, nucleic acids and proteins are polymers.
C Lipids are polymers of fatty acids and glycerol.
D Macromolecules all consist of repeating units of monomers.
Your answer [1]
3 The diagram shows part of a plasma membrane.
X
How can molecule X be described?
A It has a hydrophilic head and a hydrophobic tail.
B It is formed when the glycerol in a triglyceride is replaced by a phosphate.
© OCR 2024
, 3
C It is non-polar.
D The tails are joined to the head by peptide bonds.
Your answer [1]
4 Which statement describes a feature of plasma membranes?
A Channel proteins are a type of intrinsic protein.
B Glycolipids are intrinsic proteins that have lipid molecules attached.
C Phospholipids form a rigid bilayer that membrane proteins are attached to.
D The plasma membrane forms an impermeable barrier.
Your answer [1]
5 The adrenaline receptor is one of a class of receptors known as GPCRs. The glucagon receptor
on liver cells is another type of GPCR.
Glucagon stimulates conversion of glycogen to glucose in liver cells.
What is the action of glucagon?
A Cyclic AMP catalyses the conversion of glycogen to glucose.
B Glucagon is a second messenger.
C The glucagon receptor is located in the cytoplasm of liver cells.
D When glucagon binds to its receptor it stimulates the conversion of ATP to cyclic AMP.
Your answer [1]
6 Lymph and tissue fluid are both formed from the blood.
Which statement describes the composition of these fluids?
A Lymph contains more protein than tissue fluid because of antibody production.
B Lymph is similar in composition to tissue fluid but has more oxygen and nutrients.
C Tissue fluid does not contain hormones such as insulin and glucagon.
D Tissue fluid contains red blood cells and platelets.
© OCR 2024 Turn over
, 4
Your answer [1]
7 Which statement describes features of the mammalian heart?
A Branches of the pulmonary artery supply blood to the heart muscle.
B Semi-lunar valves prevent backflow of blood from the ventricles to the atria.
C The left ventricle pumps deoxygenated blood to the lungs.
D The wall of the left ventricle is thicker because it needs to pump blood around the whole body.
Your answer [1]
8 Bumblebees are large insects that have a high demand for oxygen during flight.
What adaptation enables bumblebees to obtain sufficient oxygen during flight?
A Accumulation of lactate in muscles during flight increases the amount of tracheal fluid which
increases the surface area for gas exchange.
B Muscle contraction before or during flight increases ventilation of the tracheal system.
C Spiracles take air directly to the respiring tissues.
D Tracheoles can open and close to allow gas exchange and minimise water loss.
Your answer [1]
9 Which option is not an adaptation that helps fish increase the efficiency of gas exchange?
A Blood capillaries lie close to the surface of the lamellae to minimise the diffusion distance.
B Blood flows in the capillaries in the same direction as the flow of water over the lamellae to
maximise gas exchange.
C Gill filaments have many lamellae that increase the surface area for gas exchange.
D Raising and lowering of the floor of the buccal cavity helps maintain a flow of water over the
gills.
Your answer [1]
10 The diagram shows part of a liver lobule.
© OCR 2024
