AS & A Level Biology - 9700 Paper 1 2015 Summer Zone 1

What are the appropriate units for measuring diameters of alveoli, diameters of white blood cells and the width of cell walls?
[Table_1]

The diagram shows a high-power drawing of a bacterium.
Which three components are found in both this bacterium and an animal cell?

The diagram shows a stage micrometer scale on which the small divisions are 0.1 mm. It is viewed through an eyepiece containing a graticule.

The stage micrometer scale is replaced by a slide of a plant cell.

What is the width of a chloroplast?

Which structures are found in typical eukaryotic cells?
1. 70S ribosomes
2. 80S ribosomes
3. linear DNA (chromosomes)
4. circular DNA

What is the function of the nucleolus?

The electronmicrograph shows a cell.
What is the actual diameter of the nucleus?

A student carried out four tests for biological molecules on a solution. The observations are shown in the table.
[Table_1]
Which molecules may be present in this solution?

The diagrams show different types of bond found in biological molecules.

Which combination of bonds could not be found in a protein with a tertiary structure?

Which row shows the correct match between the descriptions of biological molecules and where they are found?

1 a linear polymer of 1,4 linked β-glucose molecules
2 a bipolar, phosphate containing molecule
3 a highly branched polymer of 1,4 and 1,6 linked α-glucose molecules

[Table_1]

Which is the correct description for the structure of amylose and cellulose? [Table_1]

Which description is correct?

Polar molecules form hydrogen bonds with each other.
Which properties of water result from its molecules being polar?
1 good solvent
2 high specific heat capacity
3 high surface tension
4 cohesive

Which statements about the effect of all enzyme inhibitors are correct?
1. change the shape of the active site
2. denature the enzyme
3. reduce the rate of the enzyme-catalysed reaction

The graphs show the rate of reaction of an enzyme-catalysed reaction.
Which graph shows the effect of increasing the concentration of the substrate at two different concentrations of a competitive inhibitor?

Which type of cell has a large number of glycoproteins on the cell surface membrane?

The diagram shows the transport of ions across the cell surface membrane. Inside the cell there is a low concentration of sodium ions (Na⁺) and a high concentration of potassium ions (K⁺). Outside the cell there is a low concentration of K⁺ and a high concentration of Na⁺.

The carrier molecule is a pump which exchanges Na⁺ for K⁺.



Which ionic movements are represented by the arrows?

Which set of factors will produce the \textbf{most} fluid cell surface membrane?
[Table_1: A decrease in ...]

The graphs show various measurements taken from metaphase of mitosis onwards. The graphs are to scale when compared to one another.

Which row correctly identifies each graph?

A scientist counted 22 chromosomes in each of the root cells of a xerophytic plant.
What is the diploid and haploid number of chromosomes for this species?

Which row shows two pairs of nucleotides formed during transcription?
[Table_1]

Which row correctly identifies the features of DNA and RNA molecules? [Table_1]

Two polynucleotide strands make up a DNA molecule. What is a correct description?

The diagram shows transverse sections of two plant structures.

Which row shows the correct labels?

A tissue composed of plasmolysed plant cells was put into distilled water. The graph shows how the mean cell volume changes with time.
What is the cause of the plateau at X?

The diagram shows a vascular bundle from the stem of a plant.

Which row describes the functions of the labelled cells?
[Table_1]

Which changes to the water potential and the volume of liquid in the phloem occur when amino acids are moved into a sink from phloem sieve tubes?
[Table_1]

The graph shows the oxygen dissociation curves for haemoglobin from three different animals.

Which of the haemoglobins, X, Y or Z, would be present in each of the animals 1, 2 or 3?
1 an adult human
2 a fish living in water that has a very low oxygen concentration
3 a very active mammal whose tissues have a much higher rate of respiration than an adult human

What explains how the uptake of oxygen is maximised as blood passes through the capillaries of the lungs?

What happens after carbonic anhydrase has catalysed a reaction involved in the transport of carbon dioxide?

The diagram shows a section through the heart and the associated blood vessels. What is correct for the flow of blood through the heart?

Which row shows a function of each of the named tissues in the gas exchange system? [Table_1]

The graph shows the results of a study to determine whether there is a link between the number of cigarettes smoked by a mother and the birth weight of her baby.
Which conclusions can be drawn from this graph?
1. As the number of cigarettes smoked increases, the weight of the baby always decreases.
2. Factors, other than smoking, affect the birth weight of a baby.
3. Nicotine, tar and carbon monoxide slow the growth of an unborn baby.
4. The majority of all smokers smoke between 10 and 35 cigarettes per day.

What is a feature of coronary bypass surgery?

The first column in the table contains statements about disease. Columns headed 1-4 represent four different named diseases.
[Table_1]
What is the correct set of column headings for the table above?

Which row is correct for malaria?
[Table_1]

During an outbreak of a very infectious disease, vulnerable people need immediate protection.
Which type of immunity would be given to these people?
[Table_1]

Which cells become memory cells in the immune response?
1. B-lymphocytes
2. T-lymphocytes
3. phagocytes

Which soil would have the smallest number of denitrifying bacteria?

In an ecosystem, at which stage is most energy lost?

Two species of animal are found in the same area of forest and grassland. In the spring and summer they eat the same plant food. However, in the autumn and winter one eats nuts in the forest and the other eats roots on the grassland.
Both species are preyed upon by the same predator. Numbers of root-eating animals are reduced most by this, but they recover faster since they reproduce faster.
What can be concluded about these two species of animals?
1. They are part of the same community.
2. They are at different trophic levels.
3. They occupy different habitats.
4. They have different niches.