Nervous system Flashcards

Question

What is the function of the temporal lobe

Answer 1

It processes sensory information, important for hearing, recognising language and forming memories

Answer 2

Major visual processing center in the brain

Answer 3

It processes sensory information Your thalamus is your body's information relay station. All information from your body's senses (except smell) must be processed through your thalamus before being sent to your brain's cerebral cortex for interpretation.

Answer 4

Major control center for the automatic motor system. Involved in some hormonal activity and connects hormonal and nervous system. Helps regulate homeostasis

Answer 5

Produces hormone melatonin, which regulates sleep-wake cycles

Answer 6

It regulates behavioural and emotional responses. Most important parts are the hippocampus and amygdala

Answer 7

It is used to control voluntary motor movements, habit learning, eye movement, cognition and emotion

Answer 8

Coordinates gait and maintains posture. It also controls muscle tone and voluntary muscle activating, but is unable to initiate muscle contraction It receives information about: Voluntary muscle movements from cerebral cortex and from muscles, tendons and joints. And also balance

Answer 9

Connect forebrain to spinal cord and cerebellum. Responsible for vital functions of life; breathing, consciousness, blood pressure, heart rate and sleep

Answer 10

Carries motor and sensory signals between brain and periphery and coordinates reflexes Organised into segments, with each segment having a pair of spinal nerves (efferent and afferent information) There are 4 components to the spinal cord Also, the gray matter is inside the spinal cord, whereas the white matter is on the outside of the spinal cord

Answer 11

Cervical spine(8), thoracic spine(12), lumbar spine (5), sacral spine (5) The sacral region (sacrum) is at the bottom of the spine and lies between the fifth segment of the lumbar spine (L5) and the coccyx (tailbone). The sacrum is a triangular-shaped bone and consists of five segments (S1-S5) that are fused together.

Answer 12

The crossing of the right and left corticospinal tract

Answer 13

Sensory pathways decussate (cross over) from one side of the CNS to the other. As such, each cerebral hemisphere receives sensory information from opposite side of the body Motor pathways decussate from one side of CNS to the other

Answer 14

Peripheral nerves reside outside your brain and spinal cord. They relay information between your brain and the rest of your body.

Answer 15

The cranial nerves are a set of 12 paired nerves in the back of your brain. Cranial nerves send electrical signals between your brain, face, neck and torso. Your cranial nerves help you taste, smell, hear and feel sensations. They also help you make facial expressions, blink your eyes and move your tongue. they are more complicated

Answer 16

Dermatomes are areas of skin that connect to a specific nerve root on your spine.

Answer 17

Cardiac muscle Smooth muscle Exercise glands Endocrine glands

Answer 18

It is the basic structural unit of nervous system (it is a nerve cell) Each neurone is an individual cell which communicates at synapses It is a single body with dendrites and axons

Answer 19

The places where neurons connect and communicate with each other are called synapses.

Answer 20

Dendrites, nucleus, node of Ranvier, myelin sheaths, shwann cell, axon, axon terminals

Answer 21

The main function of dendrites is to receive information from other neurons, called pre-synaptic neurons, or from the environment

Answer 22

Nodes of Ranvier are gaps in the myelin sheath coating on the neural axon. The myelin allows the electrical impulse to move quickly down the axon. The nodes of Ranvier allow for ions to diffuse in and out of the neuron, propagating the electrical signal down the axon. Allows for the jumps

Answer 23

Myelin is an insulating layer, or sheath that forms around nerves, including those in the brain and spinal cord. It is made up of protein and fatty substances. This myelin sheath allows electrical impulses to transmit quickly and efficiently along the nerve cells.

Answer 24

From the broadest perspective, the function of axons is to carry electrical impulses that are the means of communication within the brain and between the brain and the rest of the body.

Answer 25

An axon terminal contains many vesicles filled with neurotransmitters which allows the neuron to conduct electrical impulse down to another neuron or another type of cell by the release of signals into the synapse.

Answer 26

Less negative charge inside cell compared to outside

Answer 27

More negative charge inside cell compared to outside, which occurs right after depolarisation

Answer 28

It has a resting potential of -70mV. This is because of the Na and K ions. This is because K+ concentration is higher inside the cell than outside, and Na+ is higher outside the cell than inside. Ultimately, there is a lower charge inside the neuron compared to outside of the neuron leading to a negative resting potential.

Answer 29

They are there to respond to a depolarisation of the cell membrane, which would cause it to open up and allow Na+ to come into the cell, further causing depolarisation in the cell. However, once it reaches a certain

Answer 30

The resting membrane potential of the neuron is at -70mV. When the dendrites receive a signal from the synaptic cleft, and the cell body decides that it is a significant enough signal (meeting the threshold potential), it leads to the staggered depolarisation of the neuron. This depolarisation is caused by the open voltage gated ion channels which allow for the influx of Na+ ions into the neuron. However, once it reaches a certain point, the voltage gated ion channels close. However, the change in membrane potential also opens the potassium voltage gated channels, causing potassium to leave the cell via diffusion. As such, this causes repolarisation. This repolarisation typically overshoots causing a hyperpolarisation, where the cell membrane potential drops below the resting potential, and eventually comes back up to equilibrium via the Na-K pump This repolarisation process is important as it allows for the signal to be transmitted down the axon without the signal being transmitted back up as it is still undergoing repolarisation and needs a higher than normal stimulus to bring it back

Answer 31

Minimum resting membrane potential for a signal to be transmitted. Anything below won't work (~-55mV)

Answer 32

The myelin increases speed of nerve conduction. It is present around nerves in the CNS and PNS and insulates axons. It is made up of about 80% lipid Here, action potentials can't be generated while myelin is wrapped around it --> prevents creation of an action potential

Answer 33

These are points on the axon which has no myelination present

Answer 34

Describes how an electrical impulse skips from node to node down the length of an axon. In myelinated axons, action potentials generated at the nodes --> saltatory conduction. This increases speed of action potential propagation compared to continuous conduction across unmyelinated axons, as they cause the action potentials to move more rapidly by 'jumping' --> speeds up transmission on axon

Answer 35

Place where neurons connect and communicate to each other

Answer 36

when an action potential reaches the axon terminal, Ca2+ moves in, allowing neurotransmitter release. Neurotransmitters diffuse across synaptic cleft to bind with receptors on the post synaptic neuron.

Answer 37

They are broken down by enzymes or undergo reputake into the presynaptic neurone

Answer 38

The synaptic cleft—also called synaptic gap—is a gap between the pre- and postsynaptic cells that is about 20 nm (0.02 μ) wide. The small volume of the cleft allows neurotransmitter concentration to be raised and lowered rapidly.

Answer 39

They are on the postsynaptic neuron and allow for the neurotransmitters to bind onto them which allows for further propagation of the action potential

Answer 40

An excitatory postsynaptic potential (EPSP) occurs when sodium channels open in response to a stimulus. The electrochemical gradient drives sodium to rush into the cell. When sodium brings its positive charge into the cell, the cell's membrane potential becomes more positive, or depolarizes.

Answer 41

An inhibitory postsynaptic potential (IPSP) is a kind of synaptic potential that makes a postsynaptic neuron less likely to generate an action potential.

Answer 42

Glutamate acts as a major excitatory neurotransmitter. It opens Na+ channels in post synaptic membranes, causing excitatory post synaptic potentials, and a depolarisation. Ultimately it increases the chances of a neuron undergoing the action potential.

Answer 43

It acts as a major inhibitory neurotransmitter. It works like this through opening Cl- channels in post synaptic membrane. This causes further hyperpolarisation, reducing the chances of the neuron being stimulated to the threshold potential, thus inhibiting the signals. Basically by opening Cl- channels, Cl- is greater in extracellular fluid compared to intracellular, and Cl- will enter the cells --> more -ve --> decreased chances of action potential occurring

Answer 44

Big stimulus from a single presynaptic terminal into a single axon --> lots of action potential --> release of glutamate into cleft --> multiple EPSPs which increase resting potential

Answer 45

Multiple synaptic inputs into multiple dendrites. Each dendrite wont have enough EPSPs on its own to trigger action potential, but together it can increase resting membrane potential to threshold potential