AQA A-Level Biology Paper 3 (7402/3) - 19th June 2024 [Exam Chat]

halfharry coming in clutch as always 😍🙏

💙💙🤭🥺🫡🫶
Side note: the examiners only sent the above and like 2 docs on how to get the best mark on the essay to teachers like LAST WEEK and so I'm reading through it and posting the best bits

can someone drop a list of all topics that did not come up in p1+2 pls

what points would you guys write for the importance of carbon dioxide as a carbon containing compound

Was just wondering if anyone could give me feedback on the style / content of my essay (this is just 2 paras of it) - this is my first practice AND IDK IF IM DOING IT RIGHT
The question was 'The importance of complementary shapes of molecules in organisms'
One process in which complementary shapes are important in organisms is in DNA replication, in which it is crucial that DNA nucleotide bases align with their complementary base pair to ensure accurate DNA replication. DNA helicase separates the complementary base pairs between two strands, and free DNA nucleotides are attracted to their complementary base pair. Cysosine aligns with guanine, and adenine with thymine, and hydrogen bonds form. In this way, accurate DNA replication is enabled to occur with the correct sequence of DNA triplets. This is important in organisms because this DNA codes for polypeptides, such as enzymes and antibodies. Therefore, if the wrong base sequences occurred, which may be the case if base pairs were not complementary, this may lead to a change in the sequence of amino acids, as a subsequent change in the position of ionic, disulphide and hydrogen bonds and teritiary sructure. This would form non-functional proteins, such as enzymes with wrong shape active site.
Another process in organisms in which complementary shapes are important in during the process of respiration, in which the enzyme ATP synthase has an active site that is complementary to protons that bind, and move through via facillitated diffusion. This process begins as protons are actively pumped from the matrix into the intermembranal space, which generates an electrochemcial gradient. Protons then bind to the active site of ATP synthase, which is complementary to its shape, and forms and enzyme-substrate complex by inducing fit. This then catalyses the reaction combining ADP + pi to form ATP. This is important in organisms as the hydrolysis of ATP is required for many energy-requiring processes, such as active transport and protein synthesis which enable organisms to survive. One way in which ATP use is crucial for survival is during absorption of glucose, as sodium ions are actively transported out of the epithelial cell, enabling sodium ions and glucose to diffuse in via co-transport. This allows glucose to be absorbed into the blood by facillitated diffusion, and therefore be taken up by cells to use in respiration.

im good at writing topics, but with saying importance, i never really know how far to go. should you go "this is important because if it didnt happen, less X woul be made, so less Y can take place .." and carry on until the organism dies 😭 i know why a process is important but i always sound like im clutching at straws, and my teacher gave me 15/25 for doing that, since he said i didnt go deep enough int importance

miss estruch planned this in one of her videos. she did glycogen, ATP, DNA, proteins, and lipids (specifically phospholipids)

try to link it to a another topic andtalk about why thats important e.g in photosynthesis glucose is produced ...then talk about the control of blood glucose levels and what would happen if it wasn't controlled

but those two dont link. it is not important for a plants survival to produce glucose from photosynthesis for blood-glucose conentration in the blood because they dont have blood

ok then link it to biodiversity and how the plant has more yield and the importance of maintaining biodiversity