Question

1.- Define homeostasis. Who was the first person to describe the phenomenon? Who was the first person to coin the term Homeostasis. Explain the processes involved in returning your body temperature to its 37°C set point during a run when your body temperature gets above 37°C.

2.-As you are sitting at your desk reviewing ANS 100 lectures during Spring 2020, you look out your window and notice a new species of animal. You remember reading about this new species Covidicus whoknowswhatitis on social media and that people don’t know much about it yet. So like a good Animal Science student you go outside to take a closer look. You see that there are lots of individuals of this species and they range in size from about 1g to 1000g. They are transparent and so you can see their internal organs (and you have superpowers so you know the weight of everything you look at!). You notice that one individual is 10g and has a 1g liver, you then notice another individual that is 30g and has a 3 g liver. In this species, does liver size scale allometrically or isometrically? Both animals turn around and now you see their kidneys. In the 10g species the kidney is 0.5g (yes, they have big kidneys) and in the 30g species the kidney is 1g. In this species, does the kidney scale allometrically or isometrically? Explain the difference between allometric and isometric scaling. Why do many physiological processes or anatomical structures scale allometrically?

Answer 1

1. Homeostasis- It is the property of cells, tissues, and organisms that allows the maintenance and regulation of the stability and constancy needed to function properly.

Claude Bernard was the first person to describe the phenomenon.

Walter Cannon was the first person to coin the term Homeostasis.

Negative feedback is the mechanism by which the body maintains conditions within particular limits. The body will do this by opposing a change that deviates from the normal.

It is important to maintain a constant temperature so that living organisms can maintain metabolism.

The temperature in mammals is detected by thermoreceptors in the skin and the hypothalamus which is in the brain. Changes in temperature bring about nerve impulses from the brain to the muscles and glands which will bring about changes depending on whether it is hot or cold.

While running, temperature of the body increases. For the temperature to return back to its normal value, following changes in the body occur:-

VASODILATION- Arterioles dilate so more blood enters skin capillaries and heat is lost.

SWEATING- Sweat glands secrete sweat which removes heat when water changes state.

PILORELAXATION- Hair of the body flattens.

STRETCHING OUT