module 5 - 14.5 coordinated responses

Question 1

what is the action of adrenaline?

Answer 1

increases heart rate
sends blood quickly to muscles and brain (adrenal medulla)
rapidly raises blood glucose concentration levels by converting glycogen to glucose

Question 2

what is the action of noradrenaline?

Answer 2

works with adrenaline in response to stress
increases heart rate
widens pupils
widens air passages in lungs
narrows blood vessels in non-essential organs

Question 3

what is the action of cortisol?

Answer 3

• helps regulate metabolism by controlling how the body converts fats, proteins and carbohydrates to energy
• helps regulate blood & cardiovascular function in response to stress (in adrenal cortex)

Question 4

what is an example of coordination between neuronal and endocrine systems?

Answer 4

fight or flight response is an example of coordination between neuronal and endocrine systems to bring about correct responses to external stimuli

Question 5

what are the ‘players’ in the fight or flight response’?

Answer 5

autonomic nervous system
adrenal cortical system
adrenaline and noradrenaline
sympathetic nervous system
glands and smooth muscle
pituitary gland
ACTH
cortisol

Question 6

what are the steps involved in the fight or flight response?

Answer 6

1. autonomic NS detects threat
2. hypothalamus communicates with
   (a) sympathetic NS and (b) adrenal cortical system
3. sympathetic NS uses nervous impulses to cause (a) adrenal medulla to release adrenaline and noradrenaline and (b) glands and smooth muscle to respond appropriately
4. hypothalamus communicates with pituitary gland
5. pituitary gland secretes ACTH
6. ACTH stimulates adrenal cortex to release (a) cortisol and (b) corticosterone

Question 7

what is the response of the communicator adrenaline?

Answer 7

increased heart rate, release of glucose by liver cells (GLYCOGENOLYSIS)

Question 8

what is the response of the communicator noradrenaline?

Answer 8

increased heart rate, widening pupils, dilation of bronchioles in lungs, vasoconstriction of non-essential organis

Question 9

what is the response of the communicator, sympathetic nervous system?

Answer 9

general effect on sphincters of the body, dilation of blood vessels for muscles, inhibition of salivation, relaxation of bladder, tunnel vision, increased muscle tension, disinhibition of spinal reflexed

Question 10

what is the response of the communicator cortisol?

Answer 10

increases blood pressure, increases blood sugar, suppresses immune system

Question 11

what is the response of the communicator corticosterone?

Answer 11

suppresses immune system and inflammatory responses in response to an infection

Question 12

what are sphincters?

Answer 12

circle muscles (in tubes) at top and bottom of stomach

Question 13

what is the action of adrenaline?

Answer 13

• promotes glycogenolysis in liver cells
• is hydrophilic and binfd to receptors in cell surface membrane of liver cells
• action of adrenaline on liver cells is cell signalling

Question 14

what are the molecules involved in the action of adrenaline?

Answer 14

• adrenaline as first messenger
• adenylyl cyclase to convert ATP to cAMP
• cAMP as a second messenger
• protein kinases to phosphorylate other enzymes
• glycogen
• glucose

Question 15

why is adrenaline hydrophilic?

Answer 15

• forms hydrogen bonds with water
• hydrophilic so has receptors, can’t get inside the membrane so uses a second messenger (cAMP)

Question 16

what is the process of adrenaline promoting glycogenolysis in liver cells?

Answer 16

adrenaline (outside cell) → receptor site on liver cell mambrane → activates adenylyl cyclase → (inside cell) coverts ATP to cAMP → activates other enzymes → converts glycogen to glucose