what (specifically) was hard about last years bio paper?
atoms make up amino acids. Amino acids make up polypeptides. Polypeptides make up proteins.
polypeptides are composed of amino acids linked by peptide bonds. proteins are made up of one or more polypeptide chains.
§ Secretion: This is the process where the body actively transports substances from the blood into the nephron. Some toxins, such as urea, tend to diffuse back into the blood, so it must be secreted back into the nephron. It is also done to regulate salt and water levels again, or to remove additional toxins. This is active transport.
So is a protein chain the chain of Amino acids joined by the peptide bonds?
so its like the beginning and happens before filtration and reabsorption?
so amino acids form polypetides.
Thankyou. So much easier than the textbook I'm reading.
my understanding is that it is done selectively to remove toxins that have diffused back into the blood. logically, these toxins would diffuse back into the blood through the reabsorption stage. the body then actively secretes the toxins that shouldn't have diffused back into the blood.
in the syllabus it doesn't specifically mention secretion but it is part of the active transport associated with kidneys as the toxins that diffused back in the blood are actively secreted into the nephron.
well there was a 5 mark question on hormone activity last year which isn't exactly hormone replacement but similar. if a question did turn up it would be more likely on this than hormone activity.