Question

1.What happens when more than one sperm fertilizes an egg? Do you get a “viable” pregnancy? Why or why not?

2.What is the role of the collecting ducts in maintaining homeostasis

Answer 1

1. A sperm is a male gamete whereas egg is a female gamete. When sperm fuses with the egg fertilization takes place resulting in formation of a zygote. The zygote formed is diploid i.e. it contains two copies of each chromosome, one from egg and the other from sperm.
When more than one sperm fuses with the egg it is known as polyspermy. It results in development of a zygote that contains three copies of chromosome, one from the egg and one from each sperm. This results in inviable pregnancy.
2. Collecting ducts are part of nephron adjacent to the distal convulated tubules. Collecting ducts are responsible for reabsorption and excretion of many ions and water under the influence of hormones and maintains homeostasis.
Aldosterone secreted from adrenal gland acts on the collecting duct to increase sodium reabsorption and increase potassium excretion. It also increases water retention. This results in increased blood volume and blood pressure and maintains homeostasis.
ADH secreted from posterior pituitary also acts on collecting duct and increases water retention. This results in increased blood volume and blood pressure. This helps maintain homeostasis.