A-level Biology Cells Exam
With answers
Name the main biological molecule in:
The Cell Membrane
The Cell Wall - answer--Phospholipids
-Murein
Has stacked membranes arranged in parallel and contains DNA. - answer-Chloroplasts
Is an organelle and is not surrounded by two membranes. - answer-Golgi Apparatus
Human breast milk is produced and secreted by gland cells. These gland cells have adaptations
that include many mitochondria and many Golgi vesicles. The milk contains a high
concentration of protein.
Explain the role of these cell adaptations in the production and secretion of breast milk. -
answer-Mitochondria release energy in the form of ATP for vesicle transportation.
Golgi Vesicles transport the protein out of the cell.
Explain the advantages of lipid droplet and micelle formation. - answer-The droplets have a
large surface area which increases the rate of hydrolysis.
The micelles are smaller so are able to pass through the membrane carrying the products.
Suggest how the Golgi apparatus is involved in the absorption of lipids. - answer-It modifies and
processes triglycerides and combines them with proteins, forms vesicles and releases them via
exocytosis.
In cell fractionation, why is the solution ice cold? - answer-Stops enzyme activity to prevent
digestion of organelles
Is RNA in a Virus or Bacterium? - answer-Both
Is a cell wall in a Virus or Bacterium? - answer-Bacterium
Are enzyme molecules in a Virus or Bacterium? - answer-Both
Is a capsid in a Virus or Bacterium? - answer-Virus
Which cell membrane, cell wall and nucleus is a is white blood cell present in? - answer-Cell
surface membrane and nucleus
Which cell membrane, cell wall and nucleus is a bacterial cell present in? - answer-Cell wall and
cell surface membrane
,Some scientists support the theory that mitochondria are organelles that evolved from
prokaryotic cells.
(i) Give one piece of evidence that supports the theory that mitochondria evolved from
prokaryotic cells. - answer-Prokaryotic cells have circular DNA
What is the advantage to cells of having mitochondria? - answer-The respire aerobically so
provides energy in the form of ATP.
Describe how temporary mounts are made. - answer-Thin slice/section;
Stain with iodine
Add cover slip;
Describe how the scientist could have used the temporary mounts of leaves to determine the
mean number of chloroplasts in mesophyll cells of a leaf. - answer-1. Take a large number of
cells
2. Count number of chloroplasts;
3. Divide number of chloroplasts by number of cells
In which organelle does protein synthesis take place? - answer-The RER
Describe how the RER is involved in the production of enzymes. - answer-Its covered in
ribosomes which join amino acids together to make proteins in protein synthesis.
Describe how the Golgi apparatus is involved in the secretion of enzymes. - answer-It modifies
and packages into vesicles for transport.
Give two structures a bacterial cell may have that a white blood cell does not have. - answer-
Flagella and capsule
People given whole-cell vaccines were more likely to develop harmful side effects than the
people given the vaccines containing parts of the bacterial cells (lines 4-6).
Suggest reasons why. - answer-Heating was supposed to kill bacteria
so active bacteria are still alive meaning they can reproduce and make toxins.
People given whole-cell vaccines produced a greater range of antibodies against the bacterium
than the people given the vaccines containing parts of the bacterial cells (lines 7-8).
, Explain why. - answer-More bacteria = antigens;
and each antigen causes its own immune response.
Microfold cells take up the antigens and transport them to cells of the immune system (lines 6-
7). Antigens are not able to pass through the cell-surface membranes of other epithelial cells.
Suggest two reasons why. - answer-Not lipid soluble
Too large
Scientists believe that it may be possible to develop vaccines that make use of microfold cells
(lines 9-10). Explain how this sort of vaccine would lead to a person developing immunity to a
pathogen. - answer-Vaccine contains antigen
T-cells activate B-cells;
B-cells divide and forms clones
Plasma cells produce antibodies;
Memory cells produced meaning more antibodies remain in system
This photograph was taken using a transmission electron microscope. The structure of the
organelles visible in the photograph could not have been seen using an optical(light)
microscope. Explain why. - answer-Has low resolution as short wavelength
Use information in the diagram to explain why vancomycin does not affect human cells. -
answer-They don't have a cell wall
Chlamydomonas has adaptations that help it to maintain a high rate of photosynthesis.
Use information in the diagram to explain what these adaptations are. - answer-Light sensitive
eyespot
Flagellum for movement
Chloroplasts for absorption
Name two structures present in an epithelial cell from the small intestine that are not present in
a cholera bacterium. - answer-Nucleus
Lysosomes
Give one advantage of using a TEM rather than a SEM. - answer-Higher resolution
Give one advantage of using a SEM rather than a TEM. - answer-3D Image
Place the appropriate letters in the correct order to show the passage of an amino acid from the
cytoplasm at F until it is secreted from the cell as a protein at K. - answer-HJE
Use the information in the figure to explain a way in which fatty acids are important in the
formation of new cells. - answer-Fatty acids respired to release energy;
More triglycerides more energy released;
With answers
Name the main biological molecule in:
The Cell Membrane
The Cell Wall - answer--Phospholipids
-Murein
Has stacked membranes arranged in parallel and contains DNA. - answer-Chloroplasts
Is an organelle and is not surrounded by two membranes. - answer-Golgi Apparatus
Human breast milk is produced and secreted by gland cells. These gland cells have adaptations
that include many mitochondria and many Golgi vesicles. The milk contains a high
concentration of protein.
Explain the role of these cell adaptations in the production and secretion of breast milk. -
answer-Mitochondria release energy in the form of ATP for vesicle transportation.
Golgi Vesicles transport the protein out of the cell.
Explain the advantages of lipid droplet and micelle formation. - answer-The droplets have a
large surface area which increases the rate of hydrolysis.
The micelles are smaller so are able to pass through the membrane carrying the products.
Suggest how the Golgi apparatus is involved in the absorption of lipids. - answer-It modifies and
processes triglycerides and combines them with proteins, forms vesicles and releases them via
exocytosis.
In cell fractionation, why is the solution ice cold? - answer-Stops enzyme activity to prevent
digestion of organelles
Is RNA in a Virus or Bacterium? - answer-Both
Is a cell wall in a Virus or Bacterium? - answer-Bacterium
Are enzyme molecules in a Virus or Bacterium? - answer-Both
Is a capsid in a Virus or Bacterium? - answer-Virus
Which cell membrane, cell wall and nucleus is a is white blood cell present in? - answer-Cell
surface membrane and nucleus
Which cell membrane, cell wall and nucleus is a bacterial cell present in? - answer-Cell wall and
cell surface membrane
,Some scientists support the theory that mitochondria are organelles that evolved from
prokaryotic cells.
(i) Give one piece of evidence that supports the theory that mitochondria evolved from
prokaryotic cells. - answer-Prokaryotic cells have circular DNA
What is the advantage to cells of having mitochondria? - answer-The respire aerobically so
provides energy in the form of ATP.
Describe how temporary mounts are made. - answer-Thin slice/section;
Stain with iodine
Add cover slip;
Describe how the scientist could have used the temporary mounts of leaves to determine the
mean number of chloroplasts in mesophyll cells of a leaf. - answer-1. Take a large number of
cells
2. Count number of chloroplasts;
3. Divide number of chloroplasts by number of cells
In which organelle does protein synthesis take place? - answer-The RER
Describe how the RER is involved in the production of enzymes. - answer-Its covered in
ribosomes which join amino acids together to make proteins in protein synthesis.
Describe how the Golgi apparatus is involved in the secretion of enzymes. - answer-It modifies
and packages into vesicles for transport.
Give two structures a bacterial cell may have that a white blood cell does not have. - answer-
Flagella and capsule
People given whole-cell vaccines were more likely to develop harmful side effects than the
people given the vaccines containing parts of the bacterial cells (lines 4-6).
Suggest reasons why. - answer-Heating was supposed to kill bacteria
so active bacteria are still alive meaning they can reproduce and make toxins.
People given whole-cell vaccines produced a greater range of antibodies against the bacterium
than the people given the vaccines containing parts of the bacterial cells (lines 7-8).
, Explain why. - answer-More bacteria = antigens;
and each antigen causes its own immune response.
Microfold cells take up the antigens and transport them to cells of the immune system (lines 6-
7). Antigens are not able to pass through the cell-surface membranes of other epithelial cells.
Suggest two reasons why. - answer-Not lipid soluble
Too large
Scientists believe that it may be possible to develop vaccines that make use of microfold cells
(lines 9-10). Explain how this sort of vaccine would lead to a person developing immunity to a
pathogen. - answer-Vaccine contains antigen
T-cells activate B-cells;
B-cells divide and forms clones
Plasma cells produce antibodies;
Memory cells produced meaning more antibodies remain in system
This photograph was taken using a transmission electron microscope. The structure of the
organelles visible in the photograph could not have been seen using an optical(light)
microscope. Explain why. - answer-Has low resolution as short wavelength
Use information in the diagram to explain why vancomycin does not affect human cells. -
answer-They don't have a cell wall
Chlamydomonas has adaptations that help it to maintain a high rate of photosynthesis.
Use information in the diagram to explain what these adaptations are. - answer-Light sensitive
eyespot
Flagellum for movement
Chloroplasts for absorption
Name two structures present in an epithelial cell from the small intestine that are not present in
a cholera bacterium. - answer-Nucleus
Lysosomes
Give one advantage of using a TEM rather than a SEM. - answer-Higher resolution
Give one advantage of using a SEM rather than a TEM. - answer-3D Image
Place the appropriate letters in the correct order to show the passage of an amino acid from the
cytoplasm at F until it is secreted from the cell as a protein at K. - answer-HJE
Use the information in the figure to explain a way in which fatty acids are important in the
formation of new cells. - answer-Fatty acids respired to release energy;
More triglycerides more energy released;
