Nervous System

Question 1

The basic organisation of the nervous system: CNS vs PNS

Answer 1

Central nervous system (CNS)
-brain and spinal cord
integrating and processing information
- sensory information to -> commands
interpreting info and making decision

Peripheral Nervous Sytem (PNS)
-everything else
commands from CNS -> body
body sensory information -> CNS

Question 2

What is the role of the nervous system in homeostasis

Answer 2

the nervous system maintains homeostasis by controlling organ systems and behavioural drives

Question 3

The structure and function of a nerve

Answer 3

Basic parts:
-cell body or soma
-axons
-Dendrites
Cell body or soma
-contains the cell nucleus
Dendrites:
-receive information from other neurons (like an antennae)

Axon
-transmits signal to another cell (nerve or tissue)
-Electrical and chemical component

Question 4

The supporting glial cells and their functions

Answer 4

Support for neurons, glial cells aid in the maintenance of homeostasis, and form myelin

Question 5

The role of myelin

Answer 5

Myelin quickens nerve signals.
Cell types that make myelin differ in CNS and PNS

Oligodendrocytes:
-central nervous system
Schwann cells:
-provide myelin for axons in peripheral nervous system

Question 6

What are action potentials?

Answer 6

There is five stages of action potential the resting potentialthsi is when the voltage of the , threshold, the rising phase, the falling phase, and the recovery phase.

Question 7

What electrolytes are required for action potentials, and the different stages of an action potential

Answer 7

The two electrolytes required for action potential are sodium and potassium. Sodium is required in depolarisation and potassium in repolaristation.

Question 8

The composition and function of myelin, and the cells that comprise it

Answer 8

Myelin quickens nerve signals.
Cell types that make myelin differ in CNS and PNS

Oligodendrocytes:
-central nervous system

Schwann cells:
-provide myelin for axons in
peripheral nervous system

Question 9

What are chemical and electrical synapses

Question 10

What are neurotransmitters and receptors

Question 11

What are key functions of each of the brain regions?

Answer 11

1. Frontal Lobes
   Function: Higher-level executive functions, including reasoning, planning, problem-solving, and judgment.
   Additional Roles: Controls voluntary movement (motor cortex), language production (Broca’s area), and aspects of personality and social behavior.
2. Parietal Lobes
   Function: Sensory processing, including touch, temperature, and pain.
   Additional Roles: Spatial awareness and coordination (sensory cortex), and integrating sensory information to form a coherent perception of the environment.
3. Temporal Lobes
   Function: Auditory processing and language comprehension.
   Additional Roles: Involved in memory formation (hippocampus) and emotional responses (amygdala).
4. Occipital Lobes
   Function: Visual processing and interpretation.
   Additional Roles: Primary visual cortex processes visual stimuli, while higher visual areas contribute to object recognition and spatial awareness.
5. Cerebellum
   Function: Coordination of voluntary movements, balance, and posture.
   Additional Roles: Fine-tunes motor activity and plays a role in motor learning.
6. Brainstem
   Function: Basic life-sustaining functions, including heart rate, breathing, and blood pressure.
   Additional Roles: Includes the midbrain, pons, and medulla oblongata; controls many reflexes and relays signals between the brain and spinal cord.
7. Hypothalamus
   Function: Regulates homeostasis by controlling body temperature, hunger, thirst, and circadian rhythms.
   Additional Roles: Links the nervous system to the endocrine system via the pituitary gland.
8. Thalamus
   Function: Relay station for sensory and motor signals to the cerebral cortex.
   Additional Roles: Plays a role in regulating consciousness, sleep, and alertness.
9. Amygdala
   Function: Emotional processing, particularly related to fear and pleasure.
   Additional Roles: Involved in forming and storing memories associated with emotional experiences.
10. Hippocampus
    Function: Essential for forming new memories and spatial navigation.
    Additional Roles: Plays a role in memory consolidation and retrieval.
11. Basal Ganglia
    Function: Regulation of movement and coordination.
    Additional Roles: Involved in motor control and learning, influencing voluntary motor activity and procedural learning.
12. Corpus Callosum
    Function: Connects the left and right cerebral hemispheres, facilitating communication between them.
    Additional Roles: Coordinates motor and sensory activities between both sides of the body.

Question 12

What are neural circuits and what is their purpose?

Answer 12

the connection of multiple neurons. they are used to communicate messages to the CNS. they play an important role in the nervous system.

Question 13

What are the key roles of the brain stem?

Answer 13

Medulla oblongata:
-regulation of cardiovascular, -respiratory, and digestive systems
Pons function:
-subconscious control of skeletal muscle
-control of smooth muscle in organs
Midbrain function:
-processing visual (sight) and auditory (sound) information
-movement reflexes
-maintenance of consciousness

Question 14

What is the role of the peripheral nervous system in homeostasis?

Answer 14

Delivers sensory information to the central nervous system
Internal and external
Position
Temperature
Pressure
Aroma
Chemical (eg capascin)
Pain stimuli (location and type)

Delivers motor commands to peripheral tissues
Conscious (skeletal muscle)
Unconscious (smooth muscle)

Question 15

What are dermatomes and how are they useful in clinical diagnosis?

Answer 15

dermatomes are the spinal cord nerves and are useful in clinical diagnosis as they allow for the identification of injuries to the spinal nerves through the inability to feel, touch or lift a body part.

Question 16

Can you describe a reflex arc, and the components of the arc?

Answer 16

Receptor:
Function: Detects the stimulus (e.g., heat, pressure, or pain).
Example: Sensory receptors in the skin that respond to a sharp object.
Sensory Neuron (Afferent Neuron):
Function: Transmits the sensory information from the receptor to the central nervous system (CNS).
Example: The neuron that carries the signal from the skin to the spinal cord.
Integration Center:
Function: Processes the sensory input and determines the appropriate response. This center is often located in the spinal cord (in spinal reflexes) or in the brainstem (in cranial reflexes).
Example: In a simple spinal reflex, the integration center is a synapse or series of synapses in the spinal cord.
Motor Neuron (Efferent Neuron):
Function: Carries the response command from the CNS to the effector.
Example: The neuron that transmits the signal from the spinal cord to a muscle.
Effector:
Function: Executes the response by acting upon the command from the motor neuron.
Example: A muscle that contracts in response to the stimulus, such as pulling your hand away from a hot surface.

Question 17

What is the role of the autonomic nervous system in homeostasis?

Answer 17

The role of the autonomic nervous system is to maintain homeostasis that is relevant ti a moment in time. It is the unconscious action directed by the braining using SNS and PSNS which work against each other to maintain homeostasis.

Question 18

What are the key roles of the sympathetic and parasympathetic nervous system components of the ANS?

Answer 18

sympathetic (fight or flight)
1. Increase Heart Rate:
Function: Accelerates the heartbeat to supply more oxygen and nutrients to muscles and vital organs.
2. Dilate Airways:
Function: Expands the bronchi in the lungs to increase airflow and enhance oxygen intake.
3. Dilate Pupils:
Function: Enlarges the pupils to improve vision and enhance sensory perception.
4. Redirect Blood Flow:
Function: Constricts blood vessels in the digestive and urinary systems while dilating those in the muscles and skin, prioritizing blood flow to areas crucial for immediate action.
5. Stimulate Glucose Release:
Function: Promotes the release of glucose from the liver to provide a quick energy source for muscles.
6. Inhibit Digestive Processes:
Function: Slows down digestion and other non-essential functions to redirect energy toward immediate physical demands.

Parasympathetic (Rets and digest)
1. Decrease Heart Rate:
Function: Slows down the heart rate to conserve energy and promote relaxation.
2. Constrict Airways:
Function: Reduces the size of the bronchi in the lungs, as less oxygen is required when the body is at rest.
3. Constrict Pupils:
Function: Narrows the pupils to reduce light entry, which helps in focusing on close objects.
4. Stimulate Digestive Processes:
Function: Enhances digestion by increasing digestive enzyme secretion and stimulating peristalsis in the gastrointestinal tract.
5. Promote Urination and Defecation:
Function: Facilitates processes related to waste elimination, which are less urgent when the body is in a relaxed state.
6. Increase Salivation:
Function: Stimulates salivary glands to aid in the initial stages of digestion.

Question 19

What are the key neurotransmitters and receptors in the SNS and PSNS in the ANS, and what are the key actions they perform?

Question 20

What are some example of how prescribed drugs can impact in the ANS?

Question 21

What are the key structures and the functions of those structures in the eye

Question 22

The roles of rods and cones

Question 23

What cranial nerves are responsible for the motor and sensory functions of the eye

Question 24

What are the key structures and the functions of those structures in the ear

Question 25

How does the ear convers sound to something we hear

Question 26

What cranial nerves carry the ear’s sensory information