Homeostasis

Question 0

How does the body respond to low water potential of cells?

Answer 0

1. Hypothalamus stimulated
2. More ADH released by pituitary gland into bloodstream into kidneys
3. Cells in walls of collecting ducts more permeable to water
4. More water reabsorbed into bloodstream.
5. Urine more concentrated, less urine produced.
6. Water potential of blood increase

Question 1

How does the body go through homeostasis?

Answer 1

Constant adjusting any changes in physical and chemical conditions of its body fluids. Eg temperature, pH, osmotic pressure.

Question 2

How does the body respond to higher concentration of glucose in the blood?

Answer 2

1. Islets of langerhans in pancreas stimulated.
2. IOL secrete insulin into bloodstream, into liver and muscles
3. Insulin increase permeability of cell surface membrane to glucose, glucose more quickly absorbed by cells.
4. Insulin causes liver and muscles to convert excess glucose to glycogen, stored in M and L.
5. Glucose in blood decreases, provides feedback to receptor to reduce insulin production.

Question 3

How does the body react when body glucose levels falls below normal?

Answer 3

1. Islets of langerhans in pan crease stimulated.
2. IOL secrete glucagon into bloodstream, transported into livers and muscles.
3. Glucagon converts glycogen to glucose, enter bloodstream.
4. Blood glucose conc increase, provide feedback to receptor to decrease glucagon production.

Question 4

What are the functions of the mammalian skin?

Answer 4

1. Protective covering over body.
2. Excretory organ.
3. Regulator to body temperature.

Question 5

Describe the innermost Malpighian layer in the skin.

Answer 5

1. Living cells
2. Contains melanin which absorbs uv rays in sunlight, damaging living cells in deeper layers of skin.
3. Prolonged exposure to sun causes pigments to appear darker.
4. Cells here undergo cell division to give new cells.
5. New cells gradually move towards surface of skin

Question 6

Describe the outer cornified layer.

Answer 6

1. Hard and waterproof dead cells.
2. Limits uncontrolled water loss by evaporation.
3. Prevents micro organisms from gaining entry into body unless there’s cut.
4. Serves as protective covering over body surfaces.

Question 7

How does your body lose heat?

Answer 7

1. Through skin by radiation, convection and a little conduction.
2. Evaporation of water in sweat from surface of skin.
3. Faeces and ur one.
4. Air being exhaled.

Question 8

What happens when body temperature is higher than normal?

Answer 8

Erector muscles relax, so hairs lie flat on skin, radiation rate increased.

1. Dilation of arterioles and constriction of shunt vessels allow more blood to flow through blood capillaries.
2. Allows more hear to be lost through skin by radiation, convection and conduction.
3. Sweat glands more active, sweat production increases, more latent heat of vaporization lost from body.4. Decreased metabolic rate, to reduce amount of heat released within body.

Question 9

What happens when human body temperature begins to fall?

Answer 9

Erector muscles attached to hair follicles contract, making hairs stand on end to trap air.

1. Constriction of skin arterioles and dilation of shunt vessels so less blood flow through capillaries in skin, reducing heat loss by convection, conduction and radiation.
2. Sweat glands less active, sweat production decreased, less latent heat of vaporization lost.
3. Increased metabolic rate, to increase amt of heat released within body.
4. Shivering occurs if too cold to increase amt of heat released.