AS & A Level Biology - 9700 Paper 1 2011 Summer Zone 1

A cell organelle measures $4 \times 10^{-1}$ mm in diameter.
What is the diameter in $\mu$m?

In the following table, which is the correct comparison between light and electron microscopes?
[Table_1: light microscope and electron microscope comparison]

Which structures are present in a typical plant cell? [Table_1]

Plant cells are stained and then viewed through a light microscope.
Which structures would be clearly visible at a magnification of ×400?

Which type of cell will contain the highest proportion of single membrane-bound structures?

Four different fruit juices, A, B, C and D, were tested with Benedict's solution. A second sample of each juice was hydrolysed and tested with Benedict’s solution. The table shows the masses of the precipitates formed.

Which juice contains the greatest mass of non-reducing sugar?

[Table_1]

Which molecular bonds will be broken by hydrolysis when a molecule of glycogen is converted to glucose?
[Table_1]

Which set of statements correctly describes haemoglobin?

Some foods contain 'hydrogenated vegetable oils'. These are unsaturated fats that have been converted to saturated fats.
Which property of the fats will have changed?

Which rows show the chemical groups present in the biological molecules listed?
[Table_1]

Which correctly matches the functional and structural features of cellulose, collagen, glycogen or triglyceride? [Table_1]

The breakdown of hydrogen peroxide to water and oxygen is catalysed by the enzyme catalase. In an investigation into the effect of pH on the rate of reaction of catalase, potato cubes were added to hydrogen peroxide. Which dependent variable should be recorded?

Which levels of protein structure can determine the specificity of an enzyme?
1 primary
2 secondary
3 tertiary
4 quaternary

Some inhibitors of enzyme reactions bind to the enzyme/substrate complex.
Which statements about this type of inhibition are correct?
1 The active site changes shape.
2 The inhibitor is non-competitive.
3 The initial rate of reaction is reduced.
4 The maximum rate of reaction ($V_{max}$) is increased.

What is correct for the cell surface membrane and membranes within cells?

What supports the view that a membrane protein is involved in active transport?

Strips of plant tissue were immersed in a range of sucrose solutions of different concentrations. Their lengths were measured before immersion and after 30 minutes.
The graph shows the ratio of initial length to final length.
What is a correct description of the change in the cells and in their water potential as the sucrose concentration increases?

Which is always true of cytokinesis?
1 Cell organelles replicate.
2 Cell organelles are divided between two cells.
3 Nuclear envelope reforms.

Which process occurs during prophase of the mitotic cell cycle in an animal cell?

The diagram shows how genetically identical frogs can be developed from unfertilised frog eggs. The diploid number (2n) for frogs is 26.
Which combination of numbers correctly identifies the number of chromosomes in each of the types of cell in the diagram?

The mechanism of action of four drugs that inhibit DNA replication is stated below.

• Aphidicholine inhibits DNA polymerase.
• Cytarabine is converted into a molecule that can substitute for a DNA nucleotide and also inhibits DNA repair mechanisms.
• Epirubicin inhibits an enzyme involved in the unwinding of DNA and separation of strands.
• Hydroxycarbamide inhibits an enzyme involved in the production of deoxyribonucleotides.

Which row correctly matches a drug to an explanation of the mechanism of action?

| | explanation of mechanism of action |
|----------------------|-----------------------------------------------------------------------------|
| | decreased pool of available nucleotides inhibits chain elongation |
| | DNA strands not available as templates for transcription |
| | DNA damaged during replication and cell death occurs |
| | exposed DNA template strands unable to be copied |
| | |
| A | aphidicholine | epirubicin | cytarabine | hydroxycarbamide | aphidicholine |
| B | epirubicin | cytarabine | hydroxycarbamide | aphidicholine |
| C | hydroxycarbamide | aphidicholine | epirubicin | cytarabine |
| D | hydroxycarbamide | epirubicin | cytarabine | aphidicholine |

The following events occur during transcription.
1. Bonds break between complementary bases.
2. Bonds form between complementary bases.
3. Sugar-phosphate bonds form.
4. Free nucleotides pair with complementary nucleotides.
Before the mRNA leaves the nucleus, which events will have occurred twice?

Which type of sugar and types of bonds are found in a DNA molecule? [Table_1]

In an animal cell, which process is dependent upon cell surface area and which process is dependent upon cell volume?
[Table_1]

Which xerophytic adaptations reduce the water potential gradient?
1 rolled leaves
2 hairy leaves
3 sunken stomata
4 fewer stomata
5 fleshy leaves

During transpiration, what is the site of evaporation of water in the leaves?

The photomicrograph shows a vascular bundle.



Which describes the relationship of water potential in the labelled cells?

The diagram represents the movement of water through a plant.

Which row identifies the processes involved during the stages of water movement shown?

What is correct for tissue fluid?
[Table_1] with columns for phagocytes, platelets, and protein concentration compared to blood plasma. Key: ✓ = present, ✗ = absent.

What happens during ventricular diastole?

Which row correctly describes the events during the cardiac cycle?
[Table_1]

Which row correctly identifies the structure of an artery compared with a vein seen in transverse section under a light microscope? [Table_1]

In the lungs, oxygen and carbon dioxide pass through cell membranes by diffusion. Which row is correct? [Table_1]

A student was asked to describe the differences between four microscope slides of sections taken from different parts of the gas exchange system.
slide 1 not present: cartilage, glands present: few goblet cells, ciliated epithelial cells, smooth muscle
slide 2 present: incomplete cartilage rings, glands, goblet cells, ciliated epithelial cells, smooth muscle
slide 3 not present: cartilage, glands, goblet cells, smooth muscle present: squamous epithelial cells
slide 4 present: plates of cartilage, glands, goblet cells, ciliated epithelial cells, smooth muscle
Which is the correct identification of the parts of the gas exchange system?
[Table_1]

A person suffering from mild emphysema stopped smoking cigarettes.
Why would this person's health improve?

Which disease is not likely to be passed directly from parents to child?

The diagram shows one way of testing the effect of an antibiotic on bacteria.

The table shows the results of testing five different types of bacteria. Zones of less than 13 mm show the presence of resistant bacteria.
[Table_1]
Which statement can be supported by this data?

Smallpox has been eradicated, but not malaria or cholera.
Which statements correctly explain this?
1. Cholera bacteria in the intestines are not destroyed by antibiotics.
2. Plasmodium antigens change during the life cycle.
3. Smallpox antigens remain stable.
4. Vaccines only work against viruses.

A square metre of grassland receives about 1 047 000 kJ of solar light energy each year.
The table shows what happens to this energy.
[Table_1]
How much energy is used by the grass in photosynthesis?

Which process does not involve making nitrogen available to plants?