Animal responses (the nervous system and the brain)

Question 1

what is the somatic response (voluntary)

Answer 1

• input - from sensory receptors in sense organs
• output - to skeletal muscles, via motor neurones.

Question 2

what is the autonomic response (involuntary)

Answer 2

• input - from internal receptors,
• outputs to smooth muscles, glands.

Question 3

what are the two types of nervous response

Answer 3

• somatic (voluntary)
• autonomic (involuntary)

Question 4

what is parasympathetic stimulation

Answer 4

• acetylcholine
• vagus nerve stimulation -> decreases HR

Question 5

what is sympathetic stimulation

Answer 5

• noradrenaline (NA)
• accelerants nerve stimulation -> increase HR

Question 6

understand the page 4 similarities and differences between somatic and autonomic nerve response.

Question 7

what is a reflex action

Answer 7

• a rapid automatic response
• follows a specific pattern in response to a given stimulus
• it is determined by the presence of an inherited pattern of neurones forming spinal and cranial reflex arcs.
• brain may be informed that reflex has happened; but is not involved in co - ordinating the reponse
• usually some sort of survival value

Question 8

reflex arc pathway (candle)

Answer 8

• stimulus - detectable change in surrounding - temperature
• receptor - thermoreceptor/ pain receptor, detects stimulus- generator potential
• sensory neurone - produces, action potential, if threshold potential is reached
• relay neurone - transmitting impulse, through CNS, between sensory + motor neurone.
• motor neurone - transmits impulse, to effector
• effector - e.g. skeletal muscle, carries out response.

Question 9

what sudden changes in the environment, may lead to blinking

Answer 9

• foreign objects, touching cornea
• bright light
• loud noise
• sudden movement

Question 10

what are the four stages in a reflex (blink reflex)

Answer 10

1. foreign object, stimulates mechanoreceptors (touch receptors) in cornea.
2. action potential, is transmitted along sensory neurone
3. action potential, is transmitted along relay neurone in the lower brain stem (pons)
4. action potential, is sent along branches of motor neurone
5. eyelid muscles around the eye, pulls eyelid inward helping to close the eyelid.

Question 11

what is the Cerebrum

Answer 11

• largest part
• conscious thought and memory
• coordinated balance and learned sequences of movement
• (unconscious functions).

Question 12

what is the medulla oblongata

Answer 12

• vital functions
• damage here can be fatal
• responsible, for forming a link, between the brain and spinal cord.

Question 13

what is the cerebral cortex

Answer 13

• the wrinkly layer on the outer surface of the cerebrum, is know as the cerebral cortex

Question 14

what are the sensory areas

Answer 14

• receiving information from sensory receptors

Question 15

what is the association areas

Answer 15

compare sensory inputs, with previous experiences

Question 16

what is the motor areas

Answer 16

sends action potentials, to effectors.

Question 17

what is the function of the hypothalamus

Answer 17

• regulation of body temperature/thirst/sleep
• monitors chemical and hormone levels, in the blood (e.g. chemoreceptors
• controls the release of hormones, like ACTH from the anterior pituitary gland

Question 18

what is the role of the anterior lobe

Answer 18

• produces ACTH (hormone) -> acts on the adrenal cortex

Question 19

what is the role of the posterior lobe

Answer 19

• directs nerve connection, within the hypothalamus
• -> neurosecretory cells, release ADH into the blood stream
• -> ADH, synthesised in the hypothalamus
• (ADH receptors, found on the plasma membranes of the collecting duct.