AS Biology Paper 1 2021 with correct answers 100%

AS Biology Paper 1 2021 with correct answers 100% Question 1.2 - Correct Answer 1489 method (4.38x10^3 / 5) x 1.7= 1489 Two differences between tRNA and mRNA structure - Correct Answer tRNA has amino acid binding site, mRNA doesn't tRNA has anticodon, mRNA has codon Difference in mRNA and pre-mRNA - Correct Answer mRNA has fewer nucleotides due to splicing Structures A and B of HIV - Correct Answer A= Attatchment protein B= capsid How HIV is replicated - Correct Answer Attachment proteins attach to receptors on helper T cells, Rna enters cell, reverse transcriptase converts RNA to DNA, enzymes produced, virus particles assembled and released Name one organelle inn digesting these bacteria (U. marinum cells) - Correct Answer Lysosomes fuse with vesicle, releases hydrolytic enzymes question 3.3 - Correct Answer 32, Actual=image/magnification Describe and explain the arrangment of genetic material in figure 4 (during prophase) - Correct Answer Chromosomes are not lined up because no spindle activity 4.2 question - Correct Answer A Fixed position occupied by gene on DNA molecule - Correct Answer Locus How a gene is a code for the production of a polypeptide - Correct Answer Base sequence in triplets determines sequence of amino acids which codes for the polypeptide Structure of glycogen relating to its function - Correct Answer Branched so compact, polymer of glucose so easily hydrolysed, branched so more ends for faster hydrolysis, glucose provides respiratory substrate for energy, insoluble so doesn't affect water potential Type of peptidases which hydrolyse bond labelled G - Correct Answer Endopeptidases 5.3 - Correct Answer 3 Pathway a red blood cell takes when travelling in the human circulatory system from a kidney to the lungs - Correct Answer Renal vein, vena cava to right atrium, right ventricle to pulmonary artery Type of blood vessel labelled M - Correct Answer Vein, wider lumen how tissue fluid is returned to the circulatory system? - Correct Answer proteins remain, water potential gradient, water moves to blood by osmosis, returns to blood by lymphatic system question 7.1 (equation one) - Correct Answer Answer 2.7 Cutting plants with a lawn mower increased the species richness of insects in that medown, why incorrect - Correct Answer Same number of species in both plots How student should use data from plot 1 and other information to estimate total number of beetle species in the meadow - Correct Answer Determine area of plot 1, calculate area of meadow, divide area of meadow by area of plot, Multiply by number of beetles Improvement to design of table and to presentation of data - Correct Answer Improvement to design of table- Independent variable in first column To presentation of data- Same number of decimal places in column on the right (0.72 not 0.7) Advantage to carrying the experiment out at 30C rather than 20C - Correct Answer Has more KE so quicker osmosis WP of egg is higher than of vinegar. Is student correct? - Correct Answer NO. Egg mass increased, water moved in by osmosis, so egg WP lower How to use calculated ratios to determine WP of eggs? State independent variable - Correct Answer Independent variable- concentration of sugar solution. Graph of ratio against concentration of sugar. Interpolate from tatio of 1; Change concentration into WP 2 organelles in kidney cells that enable production of EPO - Correct Answer Golgi apparatus and Ribosomes Biological advantage to athletes injecting synthetic EPO - Correct Answer More oxygen transport so ATP produced so exercise longer How mice injected with EPO produce anti-human EPO antibody - Correct Answer Epo displayed on antigen-presenting cells, helper T cells stimulates B cell to divide, plasma cells secrete/produce/release antibody