The Endocrine System

Question 1

What are the functions of the endocrine system?

Answer 1

• Regulate cell/organ activity within the body + maintain homeostasis
• Release hormones from glands into the bloodstream which bind to specific receptors —> imbalance may lead to dysfunction

Question 2

Describe the process of fight or flight

Answer 2

1 Brain detects a threat in the hypothalamus
2 This activates the sympathetic nervous system, initiating fight or flight response
3 Adrenaline hormone is released from adrenal glands into the bloodstream
4 Causes physiological changes in the body
5 Once threat passes, parasympathetic NS is activated, initiating rest + digest
6 parasympathetic NS causes homeostasis to occur, reversing previous changes

Question 3

Give examples of the physiological changes in the fight or flight response and why

Answer 3

• increased heart rate, more blood pumped to muscles
  -faster breathing, more O2 pumped to muscles
  -dry mouth as saliva production decreases as blood flow to digestive system decreases
  -“butterflies” = blood draining from digestive system
  -dilated pupils for better vision by letting in more light
• sweating/feeling hot, more blood @ skin surface

Question 4

Describe the structure and function of sensory neurons

Answer 4

~ long dendrites to pick up lots of sensory info
~ short axons
~ often have cell body in middle w/ two axons each side
~ carry messages from PNS to CNS

Question 5

Describe structure and function of relay neuron

Answer 5

~ have short axons and dendrites
~ connect sensory neurons to motor
~ only found in spinal cord and brain

Question 6

Describe structure and function of motor neurons

Answer 6

~ Short dendrites and long axons to reach from CNS to rest of body
~ sends messages from CNS to effectors (glands + muscles)