5.5 Plant and Animal responses ...

Question 1

what is the nervous system split in to ?

2

Answer 1

• Peripheral nervous system

- central nervous system

Question 2

what is the peripheral nervous system spilt into ?

2

Answer 2

• sensory system

- motor system

Question 3

what is the motor system split into ?

2

Answer 3

• autonomic

- somantic

Question 4

What is the autonomic nervous system split into ?

2

Answer 4

• sympathetic nervous system

- parasympathetic nervous system

Question 5

What does the sympathetic nervous system do?
effects name three
total marks :4

Answer 5

- flight or fight response ( response to stress)
increased heart rate 
dilated pupils 
increased ventilation rate 
reduced digestive activity

Question 6

where are the ganglia in the sympathetic nervous system ?

2

Answer 6

• just outside the CNS

- short pre ganglionic neurones but long post ganglionic neurones

Question 7

where are the ganglia in the parasympathetic system ?

2

Answer 7

• in effector tissue
• long neurones before
• short neurones after

Question 8

what neurotransmitter does

a) sympathetic nervous system use ?
b) parasympathetic nervous system use ?

Answer 8

• a) symp = noradrenaline

b) para= acetylcholine

Question 9

what does the cerebrum control ? 1

whats it split into ? 1

Answer 9

• conscious thought

- spilt into LHS/RHS cerebral hemispheres

Question 10

what does the cerebellum control ?

where is it ?

Answer 10

• movement and balance (leaf like at the back of head )

Question 11

what do the hypothalamus and pituitary system do ?1

Answer 11

• organise homeostatic resposes

Question 12

what does the medulla oblongata do ? 1

Answer 12

• coordination of many autonomic functions

Question 13

what areas are the cerebrum divided into ?

3

Answer 13

• sensory areas -receive AP’s from sensory neurones
• association areas - compare to previous experience and judge an appropriate response
• motor areas - AP to effector

Question 14

what are the 4 lobes of the brain ?

4

Answer 14

• frontal lobe
• parietal lobe
• temporal lobe
• occipital lobe

Question 15

what does the corpus callosum do ? 2

Answer 15

• separates the RIGHT and LEFT hemispheres of the brain

- also connects both half of the brain

Question 16

list the parts of the Brian that’d be involved in driving a car
6

Answer 16

• The visual area / visual association area
• the auditory area / auditory association area
• the motor area in the cerebrum.
• Also the cerebellum

Question 17

list part of the brain involved in answering a question verbally ?
4

Answer 17

• Auditory area
• auditory association area
• speech areas (Broca’s area)
• motor area in cerebrum.

Question 18

why are reflexes so quick ?

4

Answer 18

• they don’t involve the CNS
• Myelinated neurones
• few synapses involved
• nervous pathway is short

Question 19

When we pick up an expensive china plate , we don’t just drop it - why ?
4

Answer 19

• The eyes and nose detect that the object is of value;
• the association areas of the brain send impulses
• which inhibit the action of the synapse
• this prevents the response to let go.

Question 20

why must the action potentials to override the neurones be carried by myelinated neurones ? 1

Answer 20

• so that they are quick and arrive at the synapse in time to stop the reflex action

Question 21

what’s the difference between blinking and knee jerk reflex?

3

Answer 21

• blinking reflex is a cranial reflex so it passes through the brain = reflex arc ( 3 neurones = sensory , relay , motor)
• the knee jerk reflex = spinal reflex so it passes through he spinal cord instead of the brain
• it only has 2 neurones involved : sensory to motor

Question 22

why are digestive disorders signs of long term stress?

2

Answer 22

• One action of adrenaline is to reduce blood flow to the digestive system.
• Therefore the digestive system may not receive sufficient blood flow to operate effectively.

Question 23

how is it possible for an imagined threat to stimulate the fight or flight response ?
2

Answer 23

• The higher centres of the brain send impulses down the sympathetic part of the autonomic nervous system to the adrenal glands.
• This stimulates the release of adrenaline.

Question 24

what are the steps to coordinate the fight or flight response ?
5

Answer 24

1- AP to sensory centre in brain
2- then AP to association centre
3-if threat is recognises then CEREBRUM STIMULATES HYPOTHALAMUS
4-HYPOTHALAMUS increases activity in SYMPATHETIC NERVOUS SYSTEM .
5-PITUITARY gland secretes hormones …

Question 25

why is adrenaline a first messenger ?

1

Answer 25

• it can’t go inside of cells , but it must cause an effect inside the cell

Question 26

so how does adrenaline cause action ?

4

Answer 26

• binds to receptor which is attached to G protein on plasma membrane
• activates enzyme adenyl cyclase
• adenyl cyclase converts ATP to cAMP (secondary messenger )
• the cAMP causes the effect inside the cell

Question 27

whats the mechanism fro adrenaline action ? 4

Answer 27

• 1. adrenaline binds to receptor (complementary ) on the plasma membrane
     
     2. This is attached to a G protein , which is stimulated to activate the enzyme - ADENYL CYCLASE
     3. Adenyl cyclase converts : ATP –> cAMP= secondary messenger
     4. this causes an effect by activating enzyme action

Question 28

what does adenyl cyclase do ? 1

Answer 28

• converts ATP to cAMP

Question 29

what does the hypothalamus secrete ? 1

Answer 29

• releasing factors into the blood

- this stimulates activity in the endocrine glands

Question 30

what does CRH cause ? and where is it secreted ? 3

Answer 30

• secreted by hypothalamus

- causes the release of ACTH—-> RELEASES CORTICOSTEROID HORMONES SUCH AS CORTISOL

Question 31

What does TRH cause ? where is it secreted ?

3

Answer 31

• hypothalamus
• causes the release of thyroid stimulating hormone
• which makes the thyroid gland release thyroxine .

Question 32

what does thyroxine do ? 1

Answer 32

• makes cells more sensitive to adrenaline .

Question 33

where do we change the frequency of the heart rate?

Answer 33

• medulla oblongata

Question 34

what route does an AP take to increase heart rate ?

2 neurotransmitter ?

Answer 34

• AP down sympathetic nerve - accelerans nerve .

- causes release of noradrenaline at SAN

Question 35

route taken to decrease heart rate ?

neurotransmitter ? 2

Answer 35

• Vagus nerve

- acetylcholine

Question 36

how can we decide whether to increase or decrease the heart rate ? 3

Answer 36

• chemoreceptors
• baroreceptors
• stretch receptors
• temperature recepetors

Question 37

How do chemoreceptors change the frequency of the heart rate ?
5
how does it come back to normal ?

Answer 37

1- CO2 level increases
2-blood ph drops
3-chemoreceptors in carotid arteries increases frequency
of impulses to medulla oblongata
4-medulla oblongata = increases hear rate via sympathetic nervous system
5-heart rate increases = breathing rate increases so more CO2 is exhaled and blood PH comes back to normal .

Question 38

what do stretch receptors in muscles do ? 3

Answer 38

• detect movement of limbs so send impulses to cardiovascular centre in the medulla oblongata
  -informing that more O2 will soon be needed
  = increase in heart rate !

Question 39

what do stretch receptors in carotid sinus do ? 2

Answer 39

-monitor blood pressure
-if pressure is top high they send AP’s to medulla oblongata to reduce heart rate .
and so forth

Question 40

what are the three types of muscle ?

3 what kinds are they ?

Answer 40

• skeletal ( striated and voluntary )

- involuntary : smooth and cardiac muscle

Question 41

How is cardiac muscle specialised ?2

Answer 41

• intercalated discs - allow diffusion of ions between cells
• cross bridges to make a squeezing action

Question 42

which kind of muscle is uninucleate , what does that mean ? 2

Answer 42

• involuntary
• cardiac
  it means that each cell has its own nucleus .