Homeostasis - C6

Question 1

Define homeostasis

Answer 1

Complex, multicellular organisms are constantly exposed to environmental changes, homeostasis is the body regulating in response to these environmental factors

Question 2

When was the idea of homeostasis first proposed, and by who?

Answer 2

1930s, Walter B. Cannon

Question 3

Nervous system

Answer 3

Sensory receptors detect stimuli (temperature, PH and pressure) and motor/effector nerves can enact some responses (moving to shiver, raising hairs when cold)

Question 4

Endocrine system

Answer 4

Specialized glands release hormones into bloodstream and only specific target cells/tissues/organs have the right receptors for hormones

Question 5

Define negative feedback loop

Answer 5

When a stimulus is detected, and a response in enacted by the body to counter the stimulus, brining the body back to a baseline state

Question 6

Define positive feedback loop

Answer 6

When the stimulus, rather than being tamped down is instead amplified. This is very rare and dangerous (hyperthermia)

Question 7

Functions of the pituitary gland

Answer 7

Sends out ADH, growth hormone, stress controlling hormones, metabolic hormones, sexual reproductive and oxytocin

Question 8

Thyroid Glands

Answer 8

Front of neck, over voice box, controls metabolism, can contract hyper or hypothyroid

Question 9

Hypothalamus

Answer 9

Important role in integrating both endocrine and nervous systems

Question 10

Adrenal Gland - Medulla

Answer 10

On top of kidneys, helps heart function, fat distribution, digestive system function, adrenaline (short term stress stimulator - epinephrine), noradrenaline, works in partnership with adrenaline (norepinephrine)

Question 11

Pancreas

Answer 11

Behind stomach - produces two main hormones = insulin and glucagon

Question 12

Discuss water regulation

Answer 12

ADH tells kidneys to absorb water in collecting ducts
Insulin = converts excess glucose to glycogen via liver
Glucagon = does reverse in the liver