Biology GCSE paper 1 exam questions

reoccuring/ high mark questions (mix of 2018-2022 past papers) AQA EXAMBOARD

Figure 7 shows a model of a theory.

Explain the “lock and key” theory of the enzyme action. [3]

• enzyme binds to the substrate because they are complementary

• substrate is broken down into products

• products are released

Describe what happens during each stage of the cell cycle. [4]

• DNA duplicate

• sub cellular structures also duplicate

• one set of chromosomes is moved to each end of the cell

• the cytoplasm and cell membrane divides

It has been shown that this mAbs treatment is effective in the laboratory using both:

• infected tissue culture cells

• infected live animals

The mAbs treatment for Candida albicans is now ready for clinical trials on people

Describe how the clinical trials should be carried out. [6]

• given first to healthy volunteers at low dose,

• tested for toxicity and side effects.

• given to some people with the disease,

• tested for optimum dosage and efficency

• double blind trial

• where a placebo is used

Diffusion is an important process in both animals and plants.

What is meant by the term diffusion? [2]

• movement of particles

• from a high concentration to a low concentration

Red blood cells (RBCs) are specialised Animal cells.

compare the structures between a red blood call and an animal cell. [6]

• RBCs has no nucleus and plant cell has nucleus

• RBCs are much smaller than plant cells

• RBCs has no chloroplasts and plant cells have choloplasts

• Both contain cytoplasm

• Both contain cell membrane

compare the structures and fuctions between xylem and phloem tissues. [6]

• xylem is made of dead cells and phloem is made of living cells

• xylem does not contain cytoplasm and phloem contains cytoplasm

• Both made of cells

• Both tubular

• xylem transports water and phloem transports sugars

• both transport substances through the stem

Describe how the human body:

• prevents pathogens from entering

• defend itself against pathogens inside the body

  [6]

• Skin acts as a barrier

• Stomach acid kills bacteria

• Eyes produce tears, which is an antiseptic

• WBCs engluf pathogens

• WBCs produce antibodies to destroy pathogens

• memory cells are created

Complete word equation for photosynthesis.

_________ + ___________ → __________ + oxygen

Carbon dioxide, water, glucose

Describe a test that could be used to show that a persons urine contains gluclose. [2]

• Add benidicts solution, heat it

• If glucose is present, solution will turn brick red

Define the term double circulatory system

where blood is passed through the heart twice in one full circle

Describe how the aveoli and the villi are adapted to increase absorbtion. [4]

• both have a large surface area to maximise diffusion

• both have thin walls to reduce diffusion distance

• both have a good blood supply to maintain concentration gradient

• villi have microvilli to increase surface area

explain how a vaccination for HIV could work to prevent a person developing HIV infection. [4]

• inactive HIV injected into bloodstream

• white bloods cells produce antibodies

• correct antibodies can now be produced quicker

• antibodies destroy the active HIV