chap 3 + 4

Question 1

Transmission of a synapse

Answer 1

1. action potential arrives at axon terminal
2. voltage gated ca2+ channels open and ca2+ enters the axon terminal
3. ca2+ entry causes the neurotransmitters-containing synaptic vesicles to release their contest by exocytosis.
4. Neurotransmitters diffuse across the synaptic cleft and binds to receptors on the post synaptic membrane initiating an action potential

Question 2

resting membrane potential volatge

Answer 2

-70mv

Question 3

brain cortex functional area

Answer 3

sensory: interpret impulses from receptors
motor: Control muscle movement
Association: concerned with intellectual and emotional responses

Question 4

meninges

Answer 4

a membrane composed of three layers

Dura mater the outer layer is top and fibres and therefore provide below protection for the brain it’s Steve closely to the bones of the skull

Arachnoid mater is the middle layer and is a loose mesh of fibre

Parra mater is the inner layer and is far more delicate it contains many blood vessels and sticks closely to the surface of the brain and spinal cord

Question 5

Cerebrospinal fluid

Answer 5

Occupies the space between the middle and inner layer of meninges. It has three functions

Protection act as a shock absorber cushioning any blades or not to the central nervous system

Support: the brain is suspended inside the cranium and floats in fluid surrounds it

Transport: form from the blood and circles around the central nervous system

Question 6

medulla oblangata

Answer 6

Contains;
The cardiac Centre, which regulates the right and force of heartbeat
The respiratory centres which control the rate and depth of breath
The vet so meter centre which regulates the blood vessels diameter

Question 7

action potential

Answer 7

The opening and closing of voltage gated channels which causes the rapid depolarisation and repolarisation of the membrane lasting around one milli second.

Question 8

Grey matter and white matter

Answer 8

Grey matter contains neuron cell bodies and processes information from the sensory organ and areas\

White matter contains mile unaided axons and connects the brain with the body receptors and effectors

Question 9

Difference between involuntary action and a reflex action

Answer 9

A voluntary action new pathway would include connections to and from the brain by the spinal-cord.

A reflex action goes through the spinal-cord via the internueron runs information about the action will be sent to the brain after the action has happened

Question 10

Dopamine

Answer 10

Is the neurotransmitter responsible for relaying messages that plan and control body movement for coordination between brain and movements

Question 11

how a nerve fibre generates and propagates a nerve impulse.

Answer 11

Step 5
Resting membrane potential - Nerve fibre is resting and unstimulated. The electrical charge is at
-70mV (difference between outside and inside the cell). The cell is polarised/ charged.
Step 1
Stimulus applied - When a stimulus of 15mV+ is applied to a nerve fibre, the membrane
becomes permeable to sodium ions (Na+) and they move into the cell through sodium ion
channels. The threshold for an action potential is reached (-55mV).
Step 2
Depolarisation – Sodium ion channels open along the membrane and sodium ions (Na+)
continue to move/ flood into the cell. The cell membrane voltage rises and the inside becomes
positively charged, while the outside becomes negatively charged in comparison.
Step 3
Repolarisation - At approximately 35mV, sodium ion (Na+) channels shut and potassium ion (K+)
channels open. Potassium ions (K+) move out of the cell. Inside the cell returns to being
negatively charged and the outside positively charged.
Step 4
Hyperpolarisation – potassium ions (K+) continue to move out of the cell. Inside of cell becomes
more negative than resting potential. Sodium-potassium pumps restore a resting membrane
potential of -70mV.

Question 12

Differences between cranial and spinal nerves

Answer 12

Cranial nerves the nerves that emerge directly from the brain. They really miss information between the brain and parts of the body primarily to regions from head a neck

Spinal nerves emerge from the spinal-cord between the vertebrae. They take nerve impulses to and from the central nervous system to the rest of the body

Question 13

fluid inside cell

Answer 13

Intracellular fluid has a low concentration of sodium irons and a cord irons. Its main positive irons of potassium and negative irons come from a variety of organic substances made by the cell.

Question 14

Sodium potassium pump

Answer 14

Move to potassium ions into the cell for every three sodium ions that are moved

1. Sodium potassium pump and three sodium ions and molecules of ATP
2. The splitting of the ATP to provides energy to change the shape of the channel. The sodium ions are driven through the channel
3. The sodium irons are released to the outside of the membrane and the new shape of channel allows two potassium irons to bind
4. Release of the phosphate allows the channel 2 about its to original form, releasing the potassium irons on the inside of the membrane.

Question 15

polarised

Answer 15

When the inside of the soul is more negative than the outside it produces a negative resting membrane potential and is polarised

Question 16

strong stimulus

Answer 16

caused depolarization of more nerve fibres

produces more nerve impulses in a given time

Question 17

unmyelinated fibres

Answer 17

Depolarisation of one area causes a movement of sodium irons into the adjacent Area.
Stimulates opening of voltage gated sodium channels which initiate action potential in the next membrane
You cannot go backwards due to the refractory period action potential cannot occur

Grey in colour and slow 2 m/s

Question 18

myelinated fibres

Answer 18

Sheath insulate nerve fibre but does not nodes of ranvier
Therefore irons cannot flow between the inside and outside of membrane

Instead jumps from one node of ranvier to the next

This is called saltatory conduction

Question 19

myelinated fibres

Answer 19

Sheath insulate nerve fibre but does not nodes of Ranvier
Therefore irons cannot flow between the inside and outside of membrane

Instead jumps from one node of Ranvier to the next

This is called saltatory conduction

Question 20

insula

Answer 20

The insula controls autonomic functions through the regulation of the sympathetic and parasympathetic systems.

Question 21

polarised

Answer 21

When the inside of the cell is more negative than the outside it produces a negative resting membrane potential and is polarised

Question 22

state 4 types of structural neurons

Answer 22

unipolar- are sensory neurons connect

Question 23

state 4 types of structural neurons

Answer 23

unipolar- one extension an axon. Censoring neurons connecting receptors to the central nervous system

multipolar- one axon, multiple dendrites. Most common includes most of it into neurons in the brain and spinal cord as well as motor neurons that carry to skeletal muscles

bipolar- rare and sensory neurons associated with the eye ear and nose

Pseudounipolar- sensory neurons found in the dorsal route ganglion and majority of those in the cranial nerve sensory ganglia carry information about touch vibration proprioception pain and temperature

Question 24

dorsal root ganglion

Answer 24

Contain cell bodies for sensory neurons that carry sensory information to the spinal-cord

Question 25

types of recepters

Answer 25

Thermo receptors; response to heat or cold

Osmo receptors: concentration of substances the dissolved in the water of blood plasma

Chemo receptors: present and nose and mouth are smelling and tastes internal chemo receptors sensitive to the composition of body fluids

Touch receptors: skin hair receptors pain receptors pressure receptors fine touch stretch pressure and vibration

Pain receptors none in the brain stimulated by damaged tissue

Question 26

Reflexes

Answer 26

4 properties
Required to trigger reflex
It is involuntary
Responses rapid
Is stereotyped

Question 27

basal ganlia

Answer 27

deep inside cerebrum

grpoup of nerve cell bodies associated with control of skeletal muscle. they initiate desired movements

Question 28

frontal lobe

Answer 28

frontal lobe

thinking, problem solving, emotions, personality, language and controls movement

Question 29

parietal

Answer 29

Process temp, touch, pain, pain and movement

Question 30

temporal

Answer 30

processing memories and linking them to senses

also receives auido information

Question 31

occiptal

Answer 31

vision

Question 32

insula

Answer 32

5 th lobe

different sense and