AS & A Level Biology - 9700 Paper 1 2012 Winter Zone 1

The diagram is a drawing from an electron micrograph of a cell.
Which structure indicates that this is a secretory cell?

Four students were asked to suggest a set of four labels to add to a plan diagram of a transverse section of a dicotyledonous leaf.
Which student, A, B, C or D, suggested a correct set of labels?
[Table_1]

Which of the following are found in both eukaryotic and prokaryotic cells?
1. cellulose
2. deoxyribose
3. lipids
4. ribose

Which row correctly identifies all the locations of ribosomes in a eukaryotic cell? [Table_1]

Which statement about the light microscope is correct?

The diagram shows the ultrastructure of a cell from a dicotyledonous leaf.
What is the magnification?

Four students, 1, 2, 3 and 4, each carried out the reducing sugar test and the non-reducing sugar test on a sucrose solution.
Which observations demonstrate that they carried out the correct tests?

[Table_1]

Which row is correct for each of the molecules? [Table_1]

Which of the bonds will be last to break as the temperature of an enzyme is increased?

Which pair of monosaccharides form sucrose?

Which statement about triglycerides is correct?

Which molecules contain C=O bonds?
1 amino acids
2 fatty acids
3 glycerol

Which of the statements about polysaccharides can be used to describe both amylose and glycogen?
1 contains 1,4 glycosidic bonds
2 contains 1,6 glycosidic bonds
3 polymer of $\alpha$-glucose

What is the effect of an enzyme in an enzyme-catalysed reaction?

The diagram represents the fluid mosaic model of membrane structure.
Which two components contribute to the fluidity of the membrane?

The graph shows how the rate of entry of glucose into a cell changes as the concentration of glucose outside the cell changes. What is the cause of the plateau at X?

A molecule can enter a cell by two different passive processes.
Which process would increase the rate at which this molecule enters the cells?

Which statement is incorrect for mitotic cell division?

The diagram shows the chromosomes of one cell which has been squashed during mitosis.
Which stage of mitosis is shown and what is the haploid chromosome number in this species?

What does the process of translation require?

Which features of DNA enable it to meet these requirements as a molecule of inheritance? [Table_1]

Which diagram shows the bond linking the individual units of a nucleic acid?

Which row correctly identifies xylem vessel elements and sieve tube elements?
[Table_1]
key
✓ = present
✗ = absent

The diagram shows a model which can be used to demonstrate mass flow.

X and Y are filled with sucrose solutions of different concentrations, causing water to move in or out of X and Y by osmosis or as a result of hydrostatic pressure. Sucrose solution then moves through tube T joining X and Y.
Which description is correct?

Which of the following statements explain why a stem is both cut and connected to a potometer under water?
1. To prevent plasmolysis of xylem vessel elements
2. To prevent the collapse of xylem vessel elements
3. To prevent air entering xylem vessel elements

What happens during ventricular systole in a mammalian heart?

Which two statements about the Bohr effect are correct?
1. Increasing the partial pressure of oxygen increases the percentage of oxyhaemoglobin.
2. Decreasing the partial pressure of carbon dioxide decreases the percentage of oxyhaemoglobin.
3. Increasing the partial pressure of carbon dioxide shifts the dissociation curve of haemoglobin to the left.
4. In low concentrations of carbon dioxide haemoglobin has a high affinity for oxygen.

The diagram shows the heart and some of its blood vessels.
Which combination of numbers correctly identifies the blood vessels that supply blood to the heart and carry blood from the heart?

The diagram shows pressure changes in the left side of the heart during the cardiac cycle.
What happens at X?

The photograph shows a type of blood cell.
Which statements about these cells are correct?
1. Oxygen diffuses through the phospholipid bilayer.
2. Sodium ions diffuse through the phospholipid bilayer.
3. Water passes in and out of these cells by osmosis.

Which symptom is specific to emphysema?

Haemoglobin can bind to carbon dioxide, carbon monoxide and oxygen.
1. carbon dioxide
2. carbon monoxide
3. oxygen

Which gases share a binding site?

Some studies suggest that smoking increases the risk of developing lung cancer. The two graphs show the percentage of smokers and the deaths from lung cancer in men of two age groups between 1950 and 1998.

Which statement is not supported by the data in the graphs?

Which row correctly matches a function with B-lymphocytes and T-lymphocytes?
[Table_1]

What happens when people are injected with dead bacteria?

Some children are born with Severe Combined Immune Deficiency (SCID). These children do not normally have any T-lymphocytes and suffer from many diseases.
How may these children be cured?

Which of the following increase the risk of contracting TB?
1. drinking unpasteurised milk
2. eating shellfish which have fed on raw sewage
3. living in overcrowded conditions

Which box encloses a community?

The diagram shows a simplified nitrogen cycle.
Which arrow represents the activity of nitrogen-fixing bacteria?

The diagram shows some values for gross primary productivity (GPP) and energy flow in an ecosystem, measured in kJ m$^{-2}$ y$^{-1}$.

What percentage of GPP in the producers can be transferred to the tertiary consumers?