AQA BIOL5 ~ 17th June 2013 ~ A2 Biology

Hey guys! what sort of things could you write about in an essay question on the roles of membranes in living organisms?

Nucleic Acids (DNA/RNA)
Proteins (polypeptides)
Carbohydrates (Polysaccharides - Cellulose, Starch, Glycogen)

The different ways in which organisms use ATP OR ATP and its roles in living organisms
The nature/structure of ATP and its importance as energy currency. Production and use of ATP in cytoplasm by glycolysis Production of ATP by mitochondria in Krebs cycle and ETS – aerobic respiration. Anaerobic respiration. Role of chloroplasts in ATP production via light independent reaction Uses e.g. Active transport (carrier protein shape changes), Nerve action (maintaining resting potentials via Na+/K+ pump and resynthesis of ACh), selective reabsorption by nephron, absorption by gut, Calvin cycle, muscle contraction (cross bridge formation), Biosynthesis of organic compounds, Contractile vacuoles, Translocation (loading of phloem), cell division (movement of chromosomes via spindle), CP formation in muscles, Nitrogen fixation (Blue-green algae), Kidney function, movement of sperm, secretion of digestive enzymes in saprophytic fungi, cilia and flagella action

Thanks for this, the first 2 look hard! One question: polymers? I'm thinking of chemistry here ha, what are polymers in biology?

31. The part played by the movement of substances across cell membranes in the functioning of different organs and organs systems (June 2008).
Plasma membranes and movement across Gaseous exchange system/ lungs Digestive system/small intestine Blood vascular system Transpiration/root/stem Mass flow/leaf/stem Nervous system/eye Excretory system/ kidney Muscle systems Liver, blood glucose Root mineral ions Lungs cystic fibrosis
Any other sensible example of the movement of substances across cell membranes in the functioning of different organs and organ systems should be credited. In a good essay, the emphasis should be on movement across membranes involving organ function.

can someone just go through how adrenaline increases blood glucose conc

If your asking for cystic fibrosis then:
A faulty gene cause the cystic fibrosis transmembrane conductance regulator (CFTR) not to work properly, meaning chloride ions are transported from the cilia into the epithelial cells i think in the trachea, meaning water (moisture) in the cilia diffuses from the cilia into the epithelial cells via osmosis, because the chloride ions make the water potential lower in the epithelial cells, meaning mucus produced by (goblet?) cells is sticky. I am not sure, but i think that's right, but i wrote that from a disease point of view, so just pick out the useful stuff

can someone just go through how adrenaline increases blood glucose conc

This is wrong... Cystic Fibrosis is caused by the faulty gene (CFTR) NOT producing any chloride ions. This means that water isn't transported out of the cells so the membrane is dry, producing sticky mucus.

Ah right thanks!



All of those in bold aren't in are syllabus are they?! I don't know about any of them .That essay would be like 1/2 off syllabus content! (also by CP formation in muscles did you mean phosphocreatine? Wouldn't that be PC?)...

can someone just go through how adrenaline increases blood glucose conc

can someone just go through how adrenaline increases blood glucose conc

I thought the cftr was non functional, so does not allow the transport of chloride ions across the epithelial membrane due to its shape being unresponsive ? not that it produces chloride ions?

This is wrong... Cystic Fibrosis is caused by the faulty gene (CFTR) NOT producing any chloride ions. This means that water isn't transported out of the cells so the membrane is dry, producing sticky mucus.

Is a promoter the same as a primer?

I thought the cftr was non functional, so does not allow the transport of chloride ions across the epithelial membrane due to its shape being unresponsive ? not that it produces chloride ions?