AQA BIOLOGY

AQA A LEVEL BIOLOGY Paper 1 Questions With Accurate Answers What is the function of the cell membrane? - Accurate answers To control what enters and leaves the cell, acts as a barrier between the cell and its environment. What structural feature of the cell membrane allows substances to enter/leave? - Accurate answers Partially permeable What is the fluid mosaic model? - Accurate answers States that a membrane is a fluid structure (because phospholipids are...

AQA A LEVEL BIOLOGY IMMUNOLOGY Questions With Accurate Answers

AQA A level Biology Essay The importance of responses to changes in the internal and external environment of an organism. - Accurate answers Control of heart rate (changes in pH and pressure) Control of blood glucose (glucagon and insulin) Osmoregulation (water potential changes) Action potentials/ pacinian corpuscles (stimulus) Muscle contraction (calcium ions) Synaptic transmission (calcium ions) Natural selection (new allele) Immune response (pathogens)

AQA A LEVEL BIOLOGY - BIODIVERSITY Questions With Accurate Answers What is a community? - Accurate answers All the organisms of different species living in a habitat What is a habitat? - Accurate answers Place where an organism lives What is biodiversity? - Accurate answers the variety of life in the world or in a particular habitat or ecosystem.

AQA A LEVEL BIOLOGY Questions With Accurate Answers what are killer t-cells? - Accurate answers - cytotoxic cells - bind to non-self antigens how to killer t-cells work? - Accurate answers 1. virus attaches to and enters host cell 2. viral DNA causes host cell to express viral antigens on its surface 3. killer t-cells attaches to viral antigens on infected cells 4. killer t-cells induces death of infected cell (apoptosis) what is apoptosis? - Accurate answers...

AQA A LEVEL BIOLOGY Questions With Accurate Answers the krebs cycle takes place in the _______ of the ___________ - Accurate answers matrix mitochondria epistasis - Accurate answers arises when the allele of one gene affects or masks the expression of another in the phenotype autosome - Accurate answers a chromosome that is not a sex chromosome

AQA A LEVEL BIOLOGY: IMMUNITY Questions With Accurate Answers what are the two type of defence mechanisms? - Accurate answers specific, non specific what are two types of non specific defence mechanisms? - Accurate answers physical barrier (skin), phagocytosis what are two types of specific defence mechanisms? - Accurate answers cell mediated response, humoral response

AQA A LEVEL BIOLOGY- GENES Questions With Accurate Answers Define gene - Accurate answers A section of DNA that is a sequence of bases coding for a sequence of amino acids in a protein Define genome - Accurate answers The whole of the genetic information of an organism Define locus - Accurate answers Location of a gene on a chromosome

AQA A LEVEL BIOLOGY: SYNAPSES Questions With Accurate Answers synaptic cleft - Accurate answers a gap that separates neurons what do synapses transmit - Accurate answers neurotransmitters where is the synaptic knob located - Accurate answers the end of the axon terminal of the presynaptic neuron what is the purpose of a synapse - Accurate answers to relay information in the form of neurotransmitters in one neuron to another

aqa biology exam questions and answers 2023 with complete solution 1)What name is used for the non-coding sections of a gene? Introns Some gene mutations affect the amino acid sequence. Some mutations do not. Explain whether mutation 1 affects the amino acid sequence. No effect as it still codes for the same amino acid (Glycine) How mutation 2 could lead to the formation of a non-functional enzyme. Change in amino acid sequence Change in hydrogen and ionic bonds which alters tertiary st...