Homeostasis

Question 1

Define homeostasis

Answer 1

Keeping the internal environment constant despite external changes

Question 2

Define negative feedback loop

Answer 2

When a change in the body causes a response that reverses the change

Question 3

Define positive feedback

Answer 3

When a change occurs in the body and the response amplifies the change

Question 4

Define an endotherm

Answer 4

organisms that can maintain the temperature of their bodies within fairly strict limits independent of external changes

Question 5

Endotherm responses for high body temp

Answer 5

Sweat more, panting, hairs lie flat on skin, vasodilation (dilation of capillaries near skin), rate of metabolism decreases, no shivering

Question 6

Endotherm responses for low body temperature

Answer 6

Less sweat, no panting, hairs on skin stand on end, vasoconstriction, rate of metabolism increases, shivering

Question 7

Define an ectotherm

Answer 7

An organism who’s body temperature tends to fluctuate with the external temperature

Question 8

What causes an increase in heart rate and using which nerve

Answer 8

Stretch receptors in muscles, adrenaline in blood and low blood pH, the accelerator nerve

Question 9

What causes decrease in heart rate and by which nerve

Answer 9

High blood pressure detected by carotid sinus, vagus nerve