AQA A2 Biology Questions

Photolysis of water increases the concentration of protons in the [blank_start]thylakoid[blank_end] space.

Rubisco catalyses the reaction of [blank_start]RuBP[blank_end] with CO2 in the [blank_start]Calvin[blank_end] Cycle.

[blank_start]Glycerate[blank_end] Phosphate is converted to [blank_start]triose[blank_end] phosphate as [blank_start]1[blank_end] ATP is converted to ADP +Pi and 1 NADPH is converted to NADP ([blank_start]reducing[blank_end] the GP)

Biomass is the [blank_start]total[blank_end] mass of [blank_start]living[blank_end] material in a specific area at a specific time.

How much energy moves from one organism to another?

The [blank_start]shorter[blank_end] the food chain, the [blank_start]less[blank_end] energy loss there is so the more productive it is.

Complete this diagram of the nitrogen cycle

Complete this diagram of the Phosphorous Cycle

Complete these statements about intensive farming: -> Economically [blank_start]beneficial[blank_end] -> [blank_start]Less[blank_end] waste -> [blank_start]Reduces[blank_end] biodiversity -> [blank_start]Increases[blank_end] productivity -> Takes nutrients out of soil

The products of glycolysis are: [blank_start]2[blank_end] ATP [blank_start]2[blank_end] reduced NAD [blank_start]2[blank_end] pyruvate

Complete this flow chart for glycolysis

The link reaction occurs in the mitochondrial [blank_start]matrix[blank_end]. CO2 is released from pyruvate and the pyruvate is [blank_start]reduced[blank_end] by NAD. Co enzyme A combines with the acetate to form [blank_start]acetyl[blank_end] CoA.

Complete this diagram of the Krebs Cycle

Taxis is a response that is determined by the direction of the stimulus.

Kinesis is a plant growth movement in response to a directional stimulus.

In cell tips IAA causes cells to [blank_start]elongate[blank_end] whereas in the root tips it [blank_start]inhibits[blank_end] elongation.

As pressure is applied to the Pacinian corpuscle, the shape of the membrane changes and stretch mediated [blank_start]sodium[blank_end] ion channels are opened and [blank_start]sodium[blank_end] ions to flood in.

Rod cells respond to [blank_start]low[blank_end] light and many receptors share 1 neurone. They give [blank_start]back and white[blank_end] images. Cone cells only respond to [blank_start]high[blank_end] light intensities and each have their own sensory neurone. They give [blank_start]colour[blank_end] images.

Heart rate is controlled by the [blank_start]autonomic[blank_end] nervous system. The [blank_start]sympathetic[blank_end] nervous system speeds up the heart rate and the [blank_start]parasympathetic[blank_end] slows it down. Changes are controlled by the medulla oblongata in the [blank_start]brain[blank_end]. Changes occur due to chemical (by [blank_start]chemoreceptors[blank_end]) and pressure changes (by [blank_start]baroreceptors[blank_end])

The all or nothing principle states that if the threshold [blank_start]isn't[blank_end] reached then an action potential won't fire.

The refractory period means that action potentials [blank_start]don't[blank_end] overlap and limits the frequency at which the neve impluse can be transmitted. It causes the action potential to be [blank_start]unidirectional[blank_end].

Depolaristion occurs [blank_start]between[blank_end] Schwann cells in the [blank_start]nodes of Ranvier[blank_end].

Select the incorrect statement: During the contraction of a sarcomere,

Slow twitch muscle fibres get their energy from aerobic respiration.

Select the statements that are true about fast twitch muscle fibres

The polar bear is an [blank_start]endotherm[blank_end] so [blank_start]will[blank_end] generate it's own heat from metabolic reactions. Their body temperature [blank_start]is[blank_end] kept constant despite the envrioment.

Insulin [blank_start]lowers[blank_end] blood glucose concentration whereas glucagon [blank_start]increases[blank_end] it. Deviation from the norm is detected by α and β receptors in the [blank_start]islets of langerhans[blank_end].

Complete this diagram of the nephron

Co-dominance is when [blank_start]both[blank_end] alleles are expressed in the phenotype.

Sex-linkage is when the allele that codes for a characteristic is located on a [blank_start]sex[blank_end] chromosome. XY individuals will express a characteristic even when it is recessive since they only have [blank_start]1[blank_end] copy of it.

Complete the statements regarding the assumptions for the Hardy-Weinberg Principle: -> [blank_start]Large[blank_end] population -> [blank_start]No[blank_end] immigration -> [blank_start]No[blank_end] mutations -> [blank_start]Random[blank_end] mating

[blank_start]Allopatric[blank_end] Speciation Has geographical isolation which means that different alleles will be advantageous for the different populations so eventaually the 2 populations will change so much that they will become different species.

If there is a mutation in a tumour supressor gene, it will become inactivated and the cell will begin to divide uncontrolably.

A mutated proto-oncogene becomes an oncogene.

Unipotent cells can differentiate into a few different types of cell.

siRNA in [blank_start]plants[blank_end] is [blank_start]double[blank_end] stranded and will bind to target mRNA and [blank_start]cut[blank_end] it so it cannot be translatd.

Place the following statements about how the gene machine works in the correct order: [blank_start]2[blank_end]) Nucleotides are added step by step in the correct order [blank_start]1[blank_end]) Sequence is designed [blank_start]3[blank_end]) Short sections of DNA called oligonulceotides are produced and joined together into longer DNA fragments

During the process of PCR, the sample is heated to [blank_start]95°C[blank_end] to break the H bonds between the strands. It is then cooled to [blank_start]55°C[blank_end] so the primers can anneal. It is heated again to [blank_start]72°C[blank_end] so the DNA polymerase can work.

A VNTR is a V[blank_start]ariable[blank_end] N[blank_start]umber[blank_end] T[blank_start]andem[blank_end] R[blank_start]epeat[blank_end]

During genetic fingerprinting, the shorter fragments move the least.