Nervous system

Question 1

What are the specific functions of the nervous system?

Answer 1

Sensory input, integration and motor output

Stimulus – receptor – afferent pathway – integrated centre – efferent pathway

Question 2

What is nervous tissue made up of?

Answer 2

neurons and neuroglia cells

Question 3

What are neurons and what is their role?

Answer 3

Highly specialised nerve cells – Neurotransmission/synaptic transmission employing action protentional and neurotransmitters

Question 4

What are neuroglia and what is their role?

Answer 4

includes many cells types that protect neurons

Question 5

examples of neuroglia cells

Answer 5

largest glial cell found in the brain (CNS) are the astrocytes
smallest are microglial cells

Question 6

neurones depend on having a constant internal environment, which is effected by the ……

Answer 6

blood- brain barrier (BBB).

Question 7

What role do astrocytes have in the CNS?

Answer 7

Regulate movement of substances from blood into brain tissue, by bulbous cling to capillaries

provide physical structure and support for neurons

regulate the internal environment and neurons.
Maintain balance of Ca2+ and k+ ions

Question 8

The Blood Brain Barrier is a highly selective membrane. What are some of the clinical implications of this high selectivity?

Answer 8

Restricts the movement of microscopic pathogens into the Central nervous system.

Question 9

Draw and label a motor neuron

Answer 9

terminal buttons, 
presynaptic membrane, 
synaptic cleft,
 post synaptic membrane.
Axon
myelien sheath
Node of ranvier
axon hillock
soma
dendrite

Question 10

What is the difference between sensory neurons and motor neurons

Answer 10

Sensory neurons are efferent pathway - receptors to CNS

Motor neurons run afferent pathway - CNS- affectors

Question 11

Resting membrane potential is due too;

Answer 11

Unequal distribution of cations and anions between the inside and outside of the cell,

Question 12

Examples of cations

Answer 12

sodium/potassium/calcium ARE POSITIVELY CHARGED

Question 13

Examples of anions

Answer 13

chloride/fixed negatively charged proteins ARE NEGATIVELY CHARGED

Question 14

what does depolarisation mean?

Answer 14

polarised means difference in charge so depolarised means it is become less charged. Resting is polarised when open channels it starts depolarisation

Question 15

What is resting membrane potential?

Answer 15

Balance of positive and negative ions are across membrane results in negative resting membrane potential, intracellular proteins are fixed, by controlling the movement of sodium and potassium across the cell membrane. Membrane potential can be changed

Question 16

what is action potential?

Answer 16

In response to the appropriate stimulus, the cell membrane of a nerve cell goes through a sequence of depolarization and repolarization

Question 17

What is Nerve impulse conduction or propagation?

Answer 17

where action potentials are sequentially triggered along the length of the nerve cell membrane allowing for the signal transmission.

Question 18

What is a myelin sheath?

Answer 18

Myelin Sheath is a many layered coating that protects and insulates the axon.
Made of fatty substance called myelin.

Question 19

What are Nodes of Ranvier and their role?

Answer 19

Are gaps in the Myelin.

speed up propagation of action potential along the axon

Question 20

what are autoimmune demyelinating conditions?

Answer 20

conditions that damage myelin (body creates antibodies that attack the mylien sheath). When this happens, scar tissue forms in its place. Brain signals can’t move across scar tissue as quickly, so your nerves don’t work as well as they should

Question 21

List the events that occur at a synapse in order to perpetuate an impulse from one nerve to another

Answer 21

Step 1: Neurotransmitter synthesis

Step 2: Neurotransmitters packaging into vesicles (dopamine and ACH)

Step 3: release across synaptic cleft (exocytosis) (or Na2+) Ca 2+ ion gives instructions on how to cross. Opening channel in membrane

Step 4: Neurotransmitter binding - they now swim through synaptic cleft to the postsynaptic neuron which contains receptors and bind that translate the action potential from the vesicles. These channels let ions into the next neurone and travel along it and depolarising allowing action protentional.

Step 5: Receptors are cleared and recycled back to the presynaptic terminal to be degraded and turned back into neuro transmitters sometimes absorbed by postsynaptic terminal. Ready to repeat the cycle

Question 22

Briefly explain the mechanism of action of Fluoxetine (Prosac)

Answer 22

delay the re-uptake of serotonin, resulting in serotonin persisting longer when it is released. Acting as an antidepressant and reduces anxiety

Question 23

Neurotransmitter Excitatory and inhibitory chemical messengers allow…

Answer 23

neurons to communicate with each other at the synapse

Question 24

Central nervous system:

Answer 24

part of the nervous systems that includes the brain and the spinal cord and coordinates the motor responses of the body.

Question 25

Peripheral nervous system;

Answer 25

Part of the nervous system that includes all the nerves what are not in the brain or spinal cord.

Question 26

Somatic nervous system:

Answer 26

Part of the nervous system that coordinates the voluntary movement of skeletal muscles, sensory input from the special senses and pro-proceptive sensation from mechano-receptors in skin, joints and muscles

Question 27

Autonomic nervous system:

Answer 27

Is the functional part of the peripheral nervous system. that acts as a control centre to ensure homeostasis is maintained. These activities are generally performed without conscious control including heart rate, digestion, respiration rate, salivation, perspiration, and diameter of the pupils, micturition (urination), and sexual arousal.

Question 28

Sympathetic nervous system:

Answer 28

functions part of the autonomic nervous system that controls fight or flight response.

Question 29

Parasympathetic nervous system:

Answer 29

Part of the autonomic that regulates SLUDD (Salivation, lacrimation (tears), urination, digestion, defecation.

Question 30

Cranial Nerves

Answer 30

Part of the peripheral nervous system

Question 31

Cranial Nerves

Answer 31

Part of the peripheral nervous system in the brain stem that control head and neck motor function

Question 32

Spinal Nerves

Answer 32

peripheral nervous system. Nerves that originate in the spinal cord that control motor and sensory function of the body.

Question 33

what is the Cerebral cortex

Answer 33

part of the brain that controls emotions and feelings, memory and sensation

Question 34

functions of the Hypothalamus

Answer 34

controls homeostasis by linking nervous and endocrine systems.

Question 35

what does the Mid brain control?

Answer 35

controls vision and hearing

Question 36

what does the Cerebellum do?

Answer 36

important for the coordination, balance and perception.

Question 37

What does the brain stem control?

Answer 37

contains the controls for breathing and the heart.

Question 38

what happens in the Spinal cord

Answer 38

sensory information passing from the peripheral nervous system to the brain and motor information passing from the brain to muscles and glands found in the body

Question 39

where is the Cortico-spinal tract and what doe sit do?

Answer 39

within the spinal cord motor commands passing from the primary motor cortex to the ventral horn where upper motor neurons synapse with lower motor neurons

Question 40

what are the Meninges

Answer 40

The 3 membranes which envelop the brain and spinal cord that consist of the Dura, arachnoid mater and pia mater whose primary function is to protect the central nervous system

Question 41

what are Ventricles in the brain?

Answer 41

The cavities found in the brain and spinal cord that are filled with cerebrospinal fluid whose main functions are: buoyancy, protection, and chemical stability of the brain

Question 42

what is the Circle of Willis

Answer 42

The collateral circuit of blood vessels that is Functional Anatomy of the Autonomic Nervous System

Question 43

viscereceptors

Answer 43

receptors in the visceral organs and are attached to the autonomic sensory neurons. measure the physical and chemical internal environment

Question 44

Visceral organs

Answer 44

Heart, brain, lungs, blood vessels, urinary and gastational tracts

Question 45

examples of viscereceptors

Answer 45

Chemorecepters - measure blood CO2 mechanoreceptors - detect the degree of stretch in the walls of organs or blood vessels thermoreceptors - that measure temperature baroreceptors - that measure blood pressure

Question 46

visceral pain

Answer 46

Visceral pain occurs when pain receptors in the pelvis, abdomen, chest, or intestines are activated. We experience it when our internal organs and tissues are damaged or injured. Visceral pain is vague, not localized, and not well understood or clearly defined. It often feels like a deep squeeze, pressure, or aching.

Question 47

Somatic pain

Answer 47

Surface pain: eg. scratches Visceral pain occurs when pain receptors in the pelvis, abdomen, chest, or intestines are activated. We experience it when our internal organs and tissues are damaged or injured. Visceral pain is vague, not localized, and not well understood or clearly defined. It often feels like a deep squeeze, pressure, or aching.

Question 48

Autonomic reflexes

Answer 48

are responses that occur when nerve impulses pass through an autonomic reflex arc. These reflexes play a key role in regulating controlled conditions in the body, such as: blood pressure: by adjusting heart rate, force of ventricular contraction, and blood vessel diameter; digestion by adjusting the motility (movement) and muscle tone of the gastrointestinal tract; defecation and urination by regulating the opening and closing of sphincters.

Question 49

Dual innervation:

Answer 49

Sympathetic and parasympathetic divisions innervate mostly the same structures (e.g Gastrointestinal function)

Question 50

Antagonistic action:

Answer 50

Sympathetic and parasympathetic divisions cause opposite effects (e.g heart function)