Homeostasis

Question 1

What is homeostasis?

Answer 1

Balancing body functions to maintain a constant internal environment

Question 2

Why do conditions in your body need to be kept steady?

Answer 2

So that cells can function properly

Question 3

What are the two main conditions that need to be kept balanced in the human body?

Answer 3

Water content
Temperature

Question 4

Name 3 ways water is lost from the body?

Answer 4

-through the skin as sweat
-Via the lungs in breath
-Via the kidneys as urine

Question 4

There needs to be balance between the water you gain and the water you lose. How is water into the body?

Answer 4

What is taken in through food and drink

Question 5

Why is it important for the body temperature to remain at about 37°c?

Answer 5

Enzymes in the human body work best at about 37° C. A part of the brain acts as a personal thermostat receiving messages from temperature receptors in the skin. The nervous system can activate necessary effectors to keep the body temperature just right?

Question 6

When you are too hot, what does your body do to bring down your body temperature?

Answer 6

Sweat is produced
Blood vessels close to the surface of the skin widen
Hairs lie flat

Question 7

How does sweating cool you down?

Answer 7

Sweat evaporates and transfers energy from your skin to the environment cooling you down

Question 8

What is vasodilation?

Answer 8

Blood vessels close to the surface of the skin widen, this allows more blood to flow near the surface so it can transfer more energy into the surroundings which cools you down

Question 9

What does your body do when you’re too cold?

Answer 9

Very little sweat is produced
Blood vessels near the surface constrict
Shiver
Hair stand on end

Question 10

What is vasoconstriction?

Answer 10

Blood vessels near the surface of the skin constrict this means less blood flows near the surface so less energy energy is transferred to the surroundings

Question 11

How does shivering warm your body?

Answer 11

When you shiver, it increases your rate of respiration which transfers more energy to warm the body. Exercise does the same

Question 12

Why do your hairs stand on end to warm you up?

Answer 12

Hair stand on end to trap an insulating layer of air which helps keep you warm

Question 13

What is adrenaline? Where does it come from? What is it role and what are its effects?

Answer 13

Adrenaline comes from the adrenal glands
Adrenaline readies the body for flight or fight response
Adrenaline increases heart rate, blood flow to muscles and blood sugar level

Question 14

What is insulin? Where does it come from? What is its role and what are its effects?

Answer 14

Insulin comes from the pancreas.
It helps control the blood sugar level
Insulin stimulates the liver to turn glucose into glycogen for storage

Question 15

What is testosterone? Where does it come from? What is its role and what are its effects?

Answer 15

Testosterone comes from the testes. It is the male sex hormone testosterone, it promotes male, secondary sexual characteristics i.e. facial hair

Question 16

What is oestrogen? Where does it come from? What is its role and what are its effects?

Answer 16

Oestrogen comes from the ovaries.It is the main female sex hormone, It controls the menstrual cycle and promotes female secondary sexual characteristics

Question 17

What is progesterone? Where does it come from? What is its role and what are its effects?

Answer 17

Progesterone comes from the ovaries. It supports pregnancy. Progesterone maintains the lining of the uterus.

Question 18

What is ADH? Where does it come from? What is its role and what are its effect

Answer 18

ADH is anti diuretic hormone. ADH comes from the pituitary gland and it controls the water content of the body. ADH increases the permeability of the kidney tubules to water.

Question 19

What is FSH? Where does it come from? What is its role and what are its effects?

Answer 19

FSH comes from the pituitary gland. It is a female sex hormone. FSH causes an egg to mature in an ovary. It stimulates the ovaries to produce oestrogen.

Question 20

What is LH? Where does it come from? What is its role and what are its effects?

Answer 20

Comes from the pituitary gland. It is a female sex hormone. LH stimulates the release of an egg from an ovary.

Question 21

What are the main differences between jobs carried out by hormones and nerves?

Answer 21

Jobs carried out by nerves are fast, for a short time on a precise area
Jobs carried out by hormones are slower, act for a long time and in a more general way