The Nervous System

Question 1

What makes up the make up the central nervous system (CNS)

Answer 1

The brain and spinal cord

Question 2

What makes up the peripheral nervous system (PNS)

Answer 2

All other nervous tissue

Question 3

Functions of the Nervous System

Answer 3

Sensory Function: Detecting stimuli
Integrative Function: Analysing & integrating, storing sensory information
Motor Function: responding to sensory decisions

Question 4

What are the divisions of the Peripheral nervous system

Answer 4

Somatic Nervous System (SNS): Motor neurons carry impulses from the central nervous system to the skeletal muscles

Autonomic Nervous System (ANS):
The output (motor) part of the ANS has two branches or divisions:
Sympathetic: supports ‘fight-or-’flight’ actions
Parasympathetic: supports ‘rest-and-digest’ activities

Enteric Nervous System (ENS):
It senses changes in the gastrointestinal tract
Controls the operation of the gastrointestinal tract

Question 5

There are two types of cell that make nervous tissue

Answer 5

Neurones: sensing, thinking, remembering, controlling muscle activity, etc..

Neuroglia: support, nourish and protect neurons, maintain homeostasis around the neurons

Question 6

Action Potentials/ Synaptic Transmission

Answer 6

Synaptic transmission is the process by which one neuron communicates with another. Information is passed down the axon of the neuron as an electrical impulse known as action potential. Once the action potential reaches the end of the axon it needs to be transferred to another neuron or tissue. It must cross over the synaptic gap between the presynaptic neuron and post-synaptic neuron. At the end of the neuron (in the axon terminal) are the synaptic vesicles, which contain chemical messengers, known as neurotransmitters. When the electrical impulse (action potential) reaches these synaptic vesicles, they release their contents of neurotransmitters. Neurotransmitters then carry the signal across the synaptic gap. They bind to receptor sites on the post-synaptic cell, thereby completing the process of synaptic transmission.

Question 7

Examples of Neurotransmitters

Answer 7

Acetylcholine, Glutamate, aspartate, gamma aminobutyric acid (GABA), glycine, norepinephrine, dopamine, serotonin, neuropeptides, nitric oxide

Neurotransmitters can be either excitatory or inhibitory

Question 8

The Spinal cord is approximately how long

Answer 8

42-45cm

Question 9

How is the spinal chord protected?

Answer 9

1. The vertebral column protects the spinal cord
2. The brain and spinal cord are also surrounded by meninges:

Dura Mater (outermost)
Arachnoid Mater (middle layer)
Pia Mater (innermost layer)

3. Cerebrospinal fluid (CSF) circulates in the subarachnoid space

Question 10

How many pairs of spinal nerves are there?

Answer 10

There are 31 pairs of spinal nerves, named according to the level of the vertebral column

Question 11

What is reflex mean? What are the components?

Answer 11

are nerve impulses that follow a particular pathway known as a reflex arc

The components of a reflex arc include:
Sensory receptor
Sensory neuron
Integrating centre
Motor neuron
Effector

Question 12

The Brain consists of how many neurons and neuroglia?

Answer 12

consisting of about 85 billion neurons and 10-50 trillian neuroglia with a mass of about 1300g.

Question 13

How is the spinal cord and brain protected against chemical and physical injury?

Answer 13

cerebrospinal fluid (CSF) is clear, colourless liquid that carries oxygen, glucose, and other chemicals to neurons and neuroglia and removes their wastes and toxic substances

Question 14

Brain Stem consists of three regions? It houses?

Answer 14

Medulla oblongata
Pons
Midbrain

Cardiovascular centre, which regulates the rate and force of the heartbeat and the diameter of blood vessels

Medullary respiratory centre, which adjusts the basic rhythm of breathing

Question 15

Major regions of the diencephalon include

Answer 15

Thalamus is the major relay station for most sensory impulses that reach the cerebral cortex from the spinal cord and brainstem

Hypothalamus
- controls and integrates activities of the autonomic nervous system
- controls the pituitary gland and production of hormones; - regulation of emotions;
- regulations of eating and drinking;
- control of body temperature;
- regulation of circadian rhythms and states of consciousness

Pineal gland
- secretes the hormone melatonin, it is part of the endocrine system

Question 16

Function of the Cerebellum

Answer 16

compare intended movements programmed by the cerebral cortex with what is actually happening. It constantly receives sensory impulses from muscles, tendons, joints, and visual receptors

Question 17

Functions of the Cerebrum? What are the 4 lobes?

Answer 17

provides us with the ability to read, write, and speak; to make calculations and compose music; and to remember and to create

Each cerebral hemisphere has 4 lobes that are named after the bones that cover them:
Frontal lobe
Parietal lobe
Temporal lobe
Occipital lobe

Question 18

Functional Regions of the brain? What does the left and right hemisphere control and the functions?

Answer 18

Brain controls opposite side of the body: all sensory and motor pathways cross in CNS:
Left side of the brain controls right side of the body
Right side of the brain controls left side of the body

Left hemisphere is important for spoken and written language, numerical and scientific skills, and reasoning

Right hemisphere is more involved with spatial and pattern recognition and emotional content