Coordinated response

Question 1

What is the fight or flight response?

Answer 1

• insitinct that all mammals posses
• when a potentially dangerous situation is detected, the body automatically triggers a series of physical responses
• these are intended to help mammals survive by preparing the body to either run or fight

Question 2

How is the response triggered?

Answer 2

• Nerve impulses from sensory neurones arrive at the hypothalmus activating both the hormanal system andthe sympathetic nervous system
• the sympathetic nervous system uses neuronal pathway ot initiate body reactions whereas the adrenal-cortical system uses hormones in the bloodstream

Question 3

What is the role of the sympathetic nervous system?

Answer 3

• send out impulses to glands and smooth muscles and tells the adrenal medulla to releases adreanaline and noradrenaline into the bloodstream
• these stress hormones causes several changes in the body, including an increased heart rate

Question 4

What is the role of the pituitary gland?

Answer 4

• the release of other stress hormones which have a longer-term action from the adrenal cortex iss controlled by hormones produced by the pituitary gland in the brain

Question 5

What does the pituitary gland release?

Answer 5

• the hypothalmus stimulaties the pituitary gland to secrete ACTH
• this travels in the bloodstream to the adrenal cortex, where it activates the release of many hormones that perpare the body to deal with the threat

Question 6

What are the target cells, response and role in fligh or fight response when adreanaline is releaseD?

Answer 6

• sino-atrial node
  
  • increase rate of firing impulse
  • increased heart rate circulates blood more quickly - more oxygenated blood around the body
• Smooth muscle in bronchioles
  
  • muscle relaxes
  • bronchioles dilate and allow more oxygen to reach blood
• liver cell
  
  • increases glycogenolysis
  • makes more glucose available for respiration
• erector muscle in skin
  
  • contraction of muscle
  • causes hair to be raised so makes animal look larger / more agressive
    *

Question 7

What happens when adreanline bind to a receptor?

Answer 7

• the enzyme adenylyl cylase (which is also present in the cell membrane) is activated

Question 8

What is the purpose of the enzyme activated?

Answer 8

• converts ATP to cylcic AMP, whcih acts as a second messenger
• activates other enzymes that, in turn, convert glycogen to glucose

Question 9

What are the other fight or flight responses caused by adreanaline?

Answer 9

• pupils dilate - to take in as much liught as possible for better visison
• arterioles in skin constrictit - more blood to major muscle groups, brian, heart, and muscles of ventilation
• difficulty focusing on small tasks - brain is solely focused on threat
• non-essential system e.g. digestion shut down - resources on emergency functions

Question 10

What can be the long term adverse effects of continued exposure to stress?

Answer 10

• prolonged high blood pressure can lead to cardiovascular problems#
• prolonged high blood sugar can lead to, problems with blood sugar regulation / diabetes
• suppression of the immune system can lead to susceptibility to, disease / infection