BIOLOGY PAPER 1 AQA GCSE SET OF QUESTIONS
AND CORRECT ANSWERS ALREADY GRADED A+
GUARANTEED SUCCESS
Nucleus- DNA
Ribosomes- protein synthesis
Only plant cell organelles
Chloroplasts- hold chlorophyll for photosynthesis
Cell wall- cellulose for rigidity
Permanent vacuole- holds sap
Prokaryote cells
DNA is loose in cytoplasm
Mitochondria- respiration
What do white blood cells do?
-They can change shape to ingest microbes - this process is phagocytosis
-Others produce antibodies to fight microbes
-Some produce antitoxins to neutralise any toxins produced by the microbes
-They have a nucleus
What are stents?
-Tubes that are inserted inside arteries to keep them open which allows the blood
to pass through to the heart muscles
-They lower the risk of a heart attack in people with coronary heart disease
-They are effective for a long time
-There is a risk of infection from surgery and the patient could develop a blood clot
near the stent - thrombosis
What are statins?
,-Drugs that reduce the amount of bad cholesterol (LDL) in your bloodstream
-They slow down the rate of fatty deposits forming
-They reduce the risk of strokes, coronary heart disease and heart attacks
-They increase the amount of good cholesterol (HDL) in your bloodstream - HDL
removes LDL from the blood
-They are a long-term drug that must be taken regularly - could be forgotten to be
taken
-They can have some negative side effects e.g. headaches, kidney failure, liver
damage and memory loss
-It takes time for them to kick in
How does coronary heart disease occur?
The coronary arteries are blocked by layers of fatty material building up. It causes
the arteries to narrow therefore the blood flow is restricted and there's a lack of
oxygen to the heart - can result in a heart attack
What are artificial heart valves used for?
-If heart valves become damaged or weakened by heart attacks, infection or old
age they can stiffen up or become leaky
-Artificial heart valves replace the natural valves - they can either be mechanical or
taken from a cow or a pig
-It's less drastic than a heart transplant
-It still takes major surgery and there can be a problem with blood clotting
Meristem tissue
Found at the growing tips of roots and shoots
Able to differentiate into lots of different types of plant cell - allows the plant to
grow - plant stem cell
What is a pacemaker?
A group of cells in the right atrium wall that control the resting heart rate
, They produce a small electrical impulse which spreads to the surrounding muscle
cells, causing them to contract
Artificial pacemakers can be used to control heartbeat if the natural pacemaker
cells don't work well e.g. irregular heartbeat - they are little devices implanted
under the skin and have a wire going to the heart - they produce an electric current
to keep the heart beating regularly
Mitosis
1. Genetic material duplicates
2. Nuclear membrane dissolves
3. Two sets of chromosomes line up at centre of cell
4. Sets pulled to either side of cell
5. New nuclei forms
6. Other organelles duplicate and cell divides
7. 2 identical diploid cells
Specialisation
Stem cells can specialise to perform specific functions
Stem cells
Found in embryos and meristems
(also in bone marrow, but those can only specialise into blood cells- so can be used
for diabetes treatment)
Can be used in GM crops or to preserve a species
Embryo Clones
Make clone of an embryo of a person, extract stem cells
Done so they won't be rejected
Diffusion
Movement of particles down the concentration gradient
AND CORRECT ANSWERS ALREADY GRADED A+
GUARANTEED SUCCESS
Nucleus- DNA
Ribosomes- protein synthesis
Only plant cell organelles
Chloroplasts- hold chlorophyll for photosynthesis
Cell wall- cellulose for rigidity
Permanent vacuole- holds sap
Prokaryote cells
DNA is loose in cytoplasm
Mitochondria- respiration
What do white blood cells do?
-They can change shape to ingest microbes - this process is phagocytosis
-Others produce antibodies to fight microbes
-Some produce antitoxins to neutralise any toxins produced by the microbes
-They have a nucleus
What are stents?
-Tubes that are inserted inside arteries to keep them open which allows the blood
to pass through to the heart muscles
-They lower the risk of a heart attack in people with coronary heart disease
-They are effective for a long time
-There is a risk of infection from surgery and the patient could develop a blood clot
near the stent - thrombosis
What are statins?
,-Drugs that reduce the amount of bad cholesterol (LDL) in your bloodstream
-They slow down the rate of fatty deposits forming
-They reduce the risk of strokes, coronary heart disease and heart attacks
-They increase the amount of good cholesterol (HDL) in your bloodstream - HDL
removes LDL from the blood
-They are a long-term drug that must be taken regularly - could be forgotten to be
taken
-They can have some negative side effects e.g. headaches, kidney failure, liver
damage and memory loss
-It takes time for them to kick in
How does coronary heart disease occur?
The coronary arteries are blocked by layers of fatty material building up. It causes
the arteries to narrow therefore the blood flow is restricted and there's a lack of
oxygen to the heart - can result in a heart attack
What are artificial heart valves used for?
-If heart valves become damaged or weakened by heart attacks, infection or old
age they can stiffen up or become leaky
-Artificial heart valves replace the natural valves - they can either be mechanical or
taken from a cow or a pig
-It's less drastic than a heart transplant
-It still takes major surgery and there can be a problem with blood clotting
Meristem tissue
Found at the growing tips of roots and shoots
Able to differentiate into lots of different types of plant cell - allows the plant to
grow - plant stem cell
What is a pacemaker?
A group of cells in the right atrium wall that control the resting heart rate
, They produce a small electrical impulse which spreads to the surrounding muscle
cells, causing them to contract
Artificial pacemakers can be used to control heartbeat if the natural pacemaker
cells don't work well e.g. irregular heartbeat - they are little devices implanted
under the skin and have a wire going to the heart - they produce an electric current
to keep the heart beating regularly
Mitosis
1. Genetic material duplicates
2. Nuclear membrane dissolves
3. Two sets of chromosomes line up at centre of cell
4. Sets pulled to either side of cell
5. New nuclei forms
6. Other organelles duplicate and cell divides
7. 2 identical diploid cells
Specialisation
Stem cells can specialise to perform specific functions
Stem cells
Found in embryos and meristems
(also in bone marrow, but those can only specialise into blood cells- so can be used
for diabetes treatment)
Can be used in GM crops or to preserve a species
Embryo Clones
Make clone of an embryo of a person, extract stem cells
Done so they won't be rejected
Diffusion
Movement of particles down the concentration gradient
