(8) Homeostasis and excretion Flashcards
What is homeostasis?
It is how the body’s internal conditions are kept constant.
What is tissue fluid?
It is a watery solution of salts, glucose and other solutes. It surrounds all cells, forming a pathway to transfer nutrients.
Why is homeostasis important?
Because cells will only function properly if they are bathed in a tissue fluid that can provide them with optimum conditions.
What are two examples of nitrogenous waste?
- Urea
- Ammonia
What arteries supply blood to and from the kidneys?
The renal artery and the renal vein.
Where is urine stored in?
The bladder
What is the darker outer region of the kidney called?
The cortex, this is also where the nephrons are located.
What is the middle layer of the kidney called?
The medulla
What are pyramids?
They are bulges in the medulla, and they empty urine into a funnel like structure called the pelvis.
What is a bowman’s capsule?
It is a cup of cells that is at the start of a nephron.
What is a glomerulus?
It is a ball of capillaries that is inside of the capsule.
What are the names of the arterioles that supply blood to and from the glomerulus?
The afferent arteriole supplies blood to the glomerulus and the efferent arteriole supplies blood away from the glomerulus.
What is the membrane between the glomerulus and the bowman’s capsule?
It is the basement membrane.
What does the loop of henle do?
It is involved with concentrating the fluid in the tubule by reabsorbing more water into the blood.
What does ADH do?
It is a hormone that controls the concentration of urine.
What is a homeothermic animal?
A warm blooded animal.
Why is it important that the body temperature doesn’t get too hot?
So the enzymes don’t denature.
What is the thermoregulatory center?
It is a part of the brain that monitors the body temperature.
What is the purpose of skin?
- It forms a tough outer layer
- Acts as a barrier to prevent pathogens from entering.
- Acts as a sense organ
- Controlling the loss of heat.
What does the epidermis do?
Stop water loss and protects the body against pathogens.
What does the hypodermis do?
It consists of a layer of fatty tissue which insulates the body.
What happens when the hypothalamus detects a rise in body temperature.
- The sweat glands produce more sweat.
- The hairs on the skin lie flat against the skin.
- The arterioles in the skin dilate. (Vasodilation)
How does shivering help to heat up the body?
The rapid contractions and relaxing of the muscles generates a lot of heat.
