B2 - Exam Mistakes Flashcards
Where is DNA found?
Nucleus of the cell
In the chromosomes
What is the function of a muscle cell?
To contract and relax
What is cardiac output?
Heart rate * stroke volume (amount of blood pumped in one pump)
Why do fit people have a lower heart rate?
They have a larger stroke volume meaning the cardiac output is the same but the heart doesn’t have to work as hard because the heart rate is lower
Give 5 ways that plants use glucose
Energy Starch Protein Fats Cellulose
What does fat break down into?
Fatty acids and glycerol
Why does digesting fat decrease the pH?
Fatty acids are produced which are of course acidic
What causes the daughter cells of mitosis to be genetically identical?
The DNA is replicated to make the daughter cells
If a person has polydactyly, what is the smallest number of alleles for polydactyly that could be found in the person and why?
1
Dominant allele
Someone has cystic fibrosis. How many copies of CF allele would they need to have CF and why?
2
Recessive allele
What is the function of mitochondria? 2 marks
To transfer energy for use
By aerobic respiration
Explain why someone with a higher cardiac output can run faster. 5 marks
They send more blood to the muscles
Which supplies more oxygen
And more glucose
So faster rate of respiration
Removes more carbon dioxide and lactic acid
How do plants get energy? 2 marks
Light is absorbed
By chlorophyll in the chlotoplasts
Why did Mendel think that the production of a large amount of offspring plants improved the investigation? 3 marks
Fertilisation is random
More likely to get theoretical ratios
Anomalies have a reduced effect
Why did people not support Mendel’s ideas? 3 marks
Didn’t know about chromosomes, DNA or genes
Mendel was not part of an academic establishment
He only worked on pea plants
Why is there no difference in the effect of pepsin after pH 5? 2 marks
Pepsin denatured
ENZYME no longer fits substrate
What are the 3 main ways that animals use diffusion?
For gas exchange because of respiration (oxygen in and carbon dioxide out)
Food molecules absorbed like glucose and amino acids
Water absorption in the large intestine