Answer:
A feedback loop is a biological occurrence where the output of a system amplifies the system (positive feedback) or inhibits the system (negative feedback).
Explanation:
Example, during blood clotting, a cascade of enzymic proteins acitvates each other, leading to the formation of fibrin clot that prevents further blood loss.
Correct question:
if a nondisjunction occurs at anaphase I of the first meiotic division, what will the proportion of abnormal gametes (for the chromosomes involved in the nondisjunction)?
Answer:
100%
Explanation:
Nondisjunction at meiosis-I means that two homologous chromosomes of at least one homologous pair fail to separate from each other during anaphase-I. This would result in the formation of one cell with one extra chromosome and the other with one less chromosome by the end of meiosis-I. Meiosis-II in these two cells would maintain this chromosome number in the daughter cells. Therefore, out of the total four gametes formed by the end of the meiosis, two would have one extra chromosome and would be denoted as "n+1". The rest of the two gametes would have one less chromosome and would be denoted as "n-1".
Axons with large diameters conduct impulse faster than those with small diameters. Also Myelinated axons conduct impulse faster than unmyelinated axons. Axons with the largest diameter are all myelinated, therefore they are capable of salatory conduction (Impulses jump from one myelinated node to another). The smallest diameter axons are unmyelinated, so their conduction is continuous.
I hope this helps. :) :)
