mistakes Flashcards
which organelle has stacked membrane arranged in parallel and contains DNA
mitochondria
which organelle is not surrounded by two membranes
Golgi body
give two similarities between movement of substances by diffusion and by osmosis
both move down the gradient
passive and doesn’t require energy from respiration via ATP
name the division of cytoplasm during the cell cycle
cytokinesis
some babies are born with hole between right and the left ventricles. they are unable to get enough oxygen to their tissues
Blood flows from left ventricle to right ventricle/ mixing of oxygenated and deoxygenated blood;
- Lower volume of (oxygenated) blood leaves left ventricle/flows into aorta
Sodium ions from salt (sodium chloride) are absorbed by cells lining the gut. Some of these cells have membranes with a carrier protein called NHE3.
NHE3 actively transports one sodium ion into the cell in exchange for one proton (hydrogen ion) out of the cell.
Use your knowledge of transport across cell membranes to suggest how NHE3 does this.
Co-transport;
- Uses (hydrolysis of) ATP;
- Sodium ion and proton bind to the protein;
- Protein changes shape
Explain why all the cells of the body will have this mutation
Mutation / extra chromosome in gamete / egg / sperm (that formed zygote);
- All cells derived (from a single cell / zygote) by mitosis;
suggest how the flow of some of the blood between the aorta and pulmonary artery could cause child to die early
Less oxygenated blood flows out through aorta
Less oxygen delivered to cells / tissues
So less / not enough oxygen for aerobic respiration
Aortic valves removed from donors were stored in isotonic solution containing an antibiotic before being used in valve replacement surgery.
(a) Explain why the valves were stored in an isotonic solution
(Because) same water potential (as valve);
- (So) prevents loss or gain of water by osmosis / down water potential gradient;
- (So) cells / tissues in the valves aren’t damaged;
At Q on the diagram above there is a small increase in pressure and in rate of blood flow in the aorta.
Explain how this happens and its importance
Elastic recoil (of the aorta wall/tissue);
Reject muscle contracting.
Ignore reference to muscle relaxing.
- Smooths the blood flow
function of arteries
(aorta and pulmonary artery)
transport blood from heart to rest of the body under high pressure.
elastic middle layer
thick elastic layer
stretch and recoil . allows wall to stretch as pulse of blood flows past . stops pressure rising too high and recoils once blood passed . maintains hydrostatic pressure .
muscle middle layer
smooth muscle contracts to reduce the blood vessel diameter reducing the blood volume and increasing volume
Determining the genome of the viruses could allow scientists to develop vaccinate??
Science could identify the protein and then could identify potential antigen
Describe and explain the rule of antibodies in stimulating phagocytosis
Do not include the details about the process of phagocytosis
Antibodies bind to the antigen
Antibodies cause agglutination and attracts phagocytes
