AS & A Level Biology - 9700 Paper 1 2016 Summer Zone 3

An eyepiece graticule can be calibrated using a stage micrometer. What is the correct reason why an eyepiece graticule is calibrated?

For which cell component would nanometres be the most appropriate unit of measurement?

Which organelles are required for the formation of lysosomes containing hydrolytic enzymes?

What are found in \textbf{both} chloroplasts and mitochondria?

Which types of RNA are found in both prokaryotic and eukaryotic cells?
[Table_1]
Table Key:
✔ = present
✗ = absent

A sample of milk was tested with Benedict's solution and a yellow colour was observed.
Which conclusion is correct?

The diagrams show four monosaccharides with the formula C₆H₁₂O₆.
Which diagram shows β-glucose?

The diagram shows the relationship between different polysaccharides and the glycosidic bonds formed between the monomers.

Which row is correct?

When a small quantity of phospholipid is added to a test-tube of water and then shaken vigorously, an emulsion is formed by small droplets called liposomes.
Which diagram shows the arrangement of phospholipid molecules in a cross-section of a liposome?

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

Which statement is only true for the induced fit theory of enzyme action?

The effect of substrate concentration on an enzyme-catalysed reaction was measured in three different conditions:
• with no inhibitor
• with inhibitor X
• with inhibitor Y.
The graph shows the results:

Which statement is correct?

The list includes some of the molecules found in a cell surface membrane.
1. glycolipid
2. surface protein
3. glycoprotein
4. trans-membrane protein
Which molecules are involved in cell signalling?

Which statements about fatty acids are correct?
1 form part of cell membranes
2 form storage droplets
3 are synthesised by the Golgi body

Which substances can pass directly through cell surface membranes without using a carrier protein or channel protein?
1. $\text{Ca}^{2+}$ and $\text{Na}^{+}$
2. $\text{O}_2$
3. $\text{C}_6\text{H}_{12}\text{O}_6$

Which statements about endocytosis are correct?
1. It is a process requiring energy in the form of ATP.
2. Phagocytosis is a form of endocytosis.
3. Substances brought into a cell by endocytosis are enclosed in a small vacuole.

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

Which processes occur in bone marrow cells that are in a mitotic cell cycle?
1. phosphate groups bind to ADP molecules to form ATP
2. bonds form between nucleotides in a DNA strand
3. tRNA anticodons hydrogen bond with codons on mRNA

Which diagram shows a correct ring structure and named nucleic acid base?

Which statements are correct?
1. Adenine and cytosine are both purines.
2. The DNA nucleotide containing adenine is different from the RNA nucleotide containing adenine.
3. Purines only form base pairs with pyrimidines.

A short piece of DNA 18 base pairs long was analysed to find the number of nucleotide bases in each of the polynucleotide strands. Some of the results are shown below.

[Table_1]

How many nucleotides containing thymine were present in strand 2?

The diagram shows the nucleotide sequence of a small section of a gene which is transcribed.

CGGGCCCCGCGG

The table shows the amino acids coded for by 10 mRNA codons.

[Table_1]

What is the order of the four amino acids in the polypeptide translated from this small section of a gene?

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

Water passes across leaf tissues by different routes as a result of:
- differences in water potential
- the pull transmitted by cohesive forces between water molecules.

The diagram shows three routes by which water can travel.
Which row correctly identifies why water passes across leaf tissues by the different routes?
[Table_1]

Which factors contribute to the increase in transpiration rate when the temperature rises?
1. concentration of water molecules increases in air spaces due to evaporation
2. increased rate of diffusion as water molecules have more kinetic energy
3. increased hydrogen bonding between water molecules in air spaces

ATP is used in companion cells to provide the energy for loading a sieve tube element with sucrose. How does the co-transporter mechanism use this energy?

Which changes to the water potential and the volume of liquid in the phloem sieve tube element occur when sucrose is moved from the phloem sieve tube element to an actively dividing shoot tip?

[Table_1]

Which events occur during ventricular systole?
1. atrioventricular valves close
2. muscle in ventricle walls relaxes
3. semilunar valves open

Which components of blood are present in lymph? [Table_1]

Which row gives the correct labels for the diagram shown?

An increase in carbon dioxide in human blood shifts the oxyhaemoglobin dissociation curve to the right.
What is the explanation for this effect?

A person has two blood tests one month apart. The number of each type of cell in a fixed sample size is counted.

[Table_1]

What could this suggest about the person based on the results after one month?

Goblet cells are found in the trachea. Which organelles would be found in large numbers in a goblet cell? [Table_1]

What is the minimum number of layers of phospholipids that a molecule of oxygen passes through when diffusing from the alveoli, through cells, to haemoglobin in the red blood cells?

Which symptoms may be seen in a person affected by chronic obstructive pulmonary disease (COPD)?
1 persistent cough
2 less elastic alveoli
3 increased risk of lung infection
4 shortness of breath

More people are exposed to the risk of contracting malaria due to an increase in the distribution of *Anopheles* mosquitoes. What could be the cause of this increase?

An antibiotic inhibits the formation of cross-links between the molecules that form cell walls in bacteria.
Which statements explain why bacteria are killed by the antibiotic?
1. The bacterial cell is destroyed by osmotic lysis.
2. Cellulose molecules cannot form hydrogen bonds.
3. The cell wall is no longer selectively permeable.

Which of these pathogens can be transmitted by air?
1. \textit{Plasmodium}
2. \textit{Morbillivirus}
3. \textit{Mycobacterium}
4. \textit{Vibrio}

The graph shows the antibody response when a person is injected first with antigen X and later with antigens X and Y.
Which curve shows the primary response to antigen Y?

Which row describes passive immunity?
[Table_1]