15. Neural Control

Question 1

what is the receptor in homeostasis?

Answer 1

it detects the stimulus

Question 2

what is the control centre in homeostasis?

Answer 2

its the ‘thermostat’ - the hypothalamus

Question 3

whats the effector in homeostasis?

Answer 3

the thing that the control centre makes change - ie the ‘heater or air con’

Question 4

what is the afferent input?

Answer 4

its the sensory input

Question 5

what is the efferant output?

Answer 5

the motor output

Question 6

define negative feedback and give an example of a type

Answer 6

buildup of the end product of the sytem then shuts off.

For example thermoregulation - when its to hot or cold the receptor detects the stimulus then the control centre (hypothalamus) makes an adjustment

Question 7

what is a positive feedback loop and give an example

Answer 7

involves a change in a varable that triggers mecahnisms that amplify the change

for example the sodium potassium pump - the sodium going out stimulates potassium to come in which can then stimulate action potentials

Question 8

how does the CNS and PNS work togehter?

Answer 8

central nervous system intergrates information recieved from the periferial nervous system and makes an appropriate response

Question 9

name three things that the nervous system is capable of doing

Answer 9

1. detecting change in the internal and external enviornment
2. rapid responses of short duration
3. voluntary and involunatry responses

Question 10

where do the cranial nerves originate and go too?

Answer 10

they originate in the brain and terinate mostly in ogans of the head and upper body

Question 11

where do the spinal nerves originate and where do they go too?

Answer 11

originate in the spinal cod and go to the body below the head

Question 12

what are the four types of afferent signals

Answer 12

physical (theroreceptors)

chemical (plasma glucose)

mechanical (barroreceptors, pressure on a pen)

photreceptors (in eyes)

Question 13

what do afferent neurons do?

Answer 13

carry the signals to the central nervous system - internal and external environement

Question 14

explain the process of afferent signals, intergratin and respoonse

Answer 14

1. affrent neurons carry the signal to the CNS
2. the CNS and intergrating centre compares the input with a ‘set point’ which compares it wiht hte set value
3. the integrating centre (hypothalamus, CNS or endocrine gland) sends a motor signal (efferent) to the effector
4. effector changes the condition

Question 15

what are the two types of motor divisions?

Answer 15

somatic - concious and voluntary but the reflexes are involuntary

autonomic - controls unconsious functions (growth, digestion, breathing)

Question 16

what are the three divisions of the autonomic nervous system?

Answer 16

1. sympathetic
2. parasympathetic
3. enteric

Question 17

what do the sypathetic, parasympathetic and entric divison do (from the autonomic system)

Answer 17

sympathetc - control over organs in emergency situations

parasymathetic - recovery - ‘normal situations

entric - digestve tract, gall bladder and pancreas

Question 18

what is the similarities and differences between the symathetic and parasymathetic division? (1 of each)

Answer 18

similarities: control balance

differences: sympathetic is for excitable and parasympathetic is for ‘normal’

Question 19

why would the sypathetic divison of the autonmic system inhibit the action of the digestive system, but stimulate the release of glucose from the liver?

Answer 19

because the parasympathetic system acts in opposition to the sypathetic divison. therefore when the sympathetic division is stimulated, it opposes the parasympathetic system, therefore in ‘fight or flight mode’ the sympathetic divisin is activated