Homeostasis

Question 1

What is homeostasis?

Answer 1

the maintenance of the internal environment within restricted limits involving physiological controls

Question 2

Give 3 examples of things homeostasis regulates

Answer 2

• temperature
• blood glucose regulation
• blood ph

Question 3

Are all things homeostasis regulates controlled by hormones?

Answer 3

no

Question 4

What’s negative feedback?

Answer 4

the restoration of systems to their original level

Question 5

Describe negative feedback

Answer 5

• deviation from normal range is detected by a receptor

- leading to a corrective mechanism to restore the back to normal levels

Question 6

Describe the steps of negative feedback

Answer 6

1. receptors detected a deviation from normal range
2. hormone is secreted by a gland
3. blood transports this hormone around the body
4. the hormone binds to the target organs cells within the complementary receptor
5. triggering a cascade of reactions in the target cell

Question 7

Why is homeostasis important?

Answer 7

The enzyme activity is effected when temperature or ph fluctuates too much
-meaning metabolic reactions controlled by enzymes are impacted

Question 8

Why does blood glucose concentration need to maintained?

Answer 8

• in order to supply cells with glucose for respiration

- if not controlled the water potential of the cell are affected

Question 9

How is water potential effected when blood glucose concentration is too high?

Answer 9

• its reduced to the point where water molecules diffuse out of the cell into the blood by osmosis
• as they are moving from a area of high concentration to an area of low concentration of water
• causing cells to shrivel up and die

Question 10

How is a cell effected if blood glucose concentration is too low?

Answer 10

• cells are unable to carry out normal activities as there is not enough glucose for respiration to provide energy

Question 11

What happens if temperature increases?

Answer 11

• more heat means more kinetic energy
• molecules move faster
• substrates are more likely to collide with enzymes
• leading to the likely hood of successful enzyme substate collisions increasing
• leading to more enzyme substrate complexes being formed
  THUS INCREASING THE RATE OF REACTION

Question 12

What happens if temperature increases too much?

over 40

Answer 12

• the rise in temperate leads to enzyme molecules to vibrate more
• if the temperature rises above a certain level the vibrations will break hydrogen bonds responsible for minting the enzymes tertiary structure
• leading to a change in the enzymes 3D structure and thus their active site
• meaning enzyme substrate complexes can no longer form as the catalyst has been denatured

Question 13

Why happens when the body temperature is too low?

Answer 13

• enzyme activity is reduced

- slowing the the rate of metabolic reactions

Question 14

What happens when PH fluctuates too far from the optimum?

Answer 14

• the ionic and hydrogen bonds that hold together their tertiary structure are broken
• resulting in a change in the shape of the enzymes active site
• meaning enzyme substrate complexes can no longer form as the catalyst has been denatured

Question 15

What is the equation for PH?

Answer 15

PH= -log10 [H+]

Question 16

Describe the response of Insulin and Glucagon compared to a nervous response

Answer 16

• slower response than nervous responses
• response concours all over the body
• longer lasting as broken down less rapidly