The Nervous System

Question 1

What are the 2 classifications of the nervous system?

Answer 1

• Central Nervous System (CNS)
• Peripheral Nervous System (PNS)

Question 2

What does the CNS consist of?

Answer 2

The brain and spinal cord

Question 3

What does the PNS consist of?

Answer 3

Sensory and motor neurons

Question 4

What are the 3 types of neurons?

Answer 4

• Sensory
• Motor
• Interneurons

Question 5

What are sensory neurons?

Answer 5

Receptors embedded in the skin, organs and muscles which transmit signals to interneurons

Question 6

What are interneurons?

Answer 6

Neurons that transmit signals between other neurons

Question 7

What are motor neurons?

Answer 7

Neurons with long axons to extend and send a signal to effectors, such as muscles and glands

Question 8

What is the myelin sheath?

Answer 8

Many schwaan cells, which allow a faster conduction than non-myelinated neurons

Question 9

What is the membrane potential?

Answer 9

Electrical difference between the inside and outside of the cell

Question 10

What is a resting potential?

Answer 10

Sodium pumps sodium ions outside the cell via ATP, so the inside of the cell becomes negative

Question 11

What is an action potential?

Answer 11

Sodium channels open and sodium ions rush inside the cell, so the inside of the cell becomes positive.

Question 12

What is a synapse?

Answer 12

A gap between two neurons, where neurotransmitters are released to cause a specific effect

Question 13

What are the 3 areas of the brain?

Answer 13

• Forebrain
• Midbrain
• Hindbrain

Question 14

What does the forebrain consist of?

Answer 14

• Cerebrum
• Olfactory bulbs
• Thalamus
• Hypothalamus

Question 15

What is the hindbrain consist of?

Answer 15

• Cerebellum
• Brainstem

Question 16

What does the cerebrum of the forebrain do?

Answer 16

• Conscious awareness of sensory input
• Controls all voluntary actions
• Personality
• Memory
• Learning

Question 17

What does the olfactory bulbs of the forebrain do?

Answer 17

Relay smell data to cerebrum

Question 18

What does the thalamus of the forebrain do?

Answer 18

Relays data from special data to cerebrum

Question 19

What does the hypothalamus of the forebrain do?

Answer 19

• Links the endocrine and nervous system together
• Maintains homeostasis

Question 20

What does the cerebellum of the hindbrain do?

Answer 20

Controls balance and coordination

Question 21

What does the brainstem of the hindbrain do?

Answer 21

Controls vital functions such as respiratory rate, heart rate, swallowing and vomiting

Question 22

What are the 4 things that protect the brain?

Answer 22

• Cranium
• Meninges
• Cerebrospinal fluid (CSF)
• Blood brain barrier (BBB)

Question 23

What are meninges?

Answer 23

• Protective layers made up of connective tissue membranes around the brain, which has cerebrospinal fluid between the arachnoid mater and the pia mater

Question 24

What are the 3 layers of meninges?

Answer 24

• Dura mater: tough membrane
• Arachnoid mater: thinner membrane
• Pia mater: delicate membrane covering brain

Question 25

What is the blood brain barrier and what does it do?

Answer 25

- Neuroglial cells that surround capillaries to make them not leaky - Protects the brain from harmful substances and infections - Permeable to oxygen and glucose

Question 26

What is the spinal cord?

Answer 26

- A cord that exits the skulls and runs inside the vertebral canal, giving off pairs of spinal nerves and the splits into several nerves called the cauda equina - Grey matter: cell bodies and unmyelinated fibres - White matter: myelinated fibres, ascending and descending tracts

Question 27

What are the 3 things that protect the spinal cord?

Answer 27

- Vertebrae - Meninges - Cerebrospinal fluid

Question 28

How do meninges protect the spinal cord?

Answer 28

Space between the vertebrae and dura mater are filled with fat and capillaries

Question 29

What are sensory neurons that are classed as conscious?

Answer 29

Neurons that relate the animal to the environment

Question 30

What are sensory neurons that are classed as unconscious?

Answer 30

Neurons that monitor digestion and metabolism

Question 31

What are motor neurons that are classed as conscious?

Answer 31

Neurons that regulate body movement by control of skeletal muscle

Question 32

What are motor neurons that are classed as unconscious?

Answer 32

Neurons that are autonomic in the smooth and cardiac muscles as well as glands

Question 33

How many major cranial nerves (mnemonic) are they?

Answer 33

12

Question 34

What is the I nerve?

Answer 34

Olfactory

Question 35

What is the II nerve?

Answer 35

Optic

Question 36

What is the III nerve?

Answer 36

Oculomotor

Question 37

What is the IV nerve?

Answer 37

Trochlear

Question 38

What is the V nerve?

Answer 38

Trigeminal

Question 39

What is the VI nerve?

Answer 39

Abducens

Question 40

What is the VII nerve?

Answer 40

Facial motors

Question 41

What is the VIII nerve?

Answer 41

Vestibulocochlear/Auditory

Question 42

What is the IX nerve?

Answer 42

Glossopharyngeal

Question 43

What is the X nerve?

Answer 43

Vagus

Question 44

What is the XI nerve?

Answer 44

Accessory

Question 45

What is the XII nerve?

Answer 45

Hypoglossal

Question 46

What is the brachial plexus?

Answer 46

Spinal nerves C6, C7, C8, T1, and T2 which supply the foreleg

Question 47

What is the lumbosacral plexus?

Answer 47

Spinal nerves L3, L4, L5, L6, L7, S1, and S2, which supply the hindleg

Question 48

What is a radial nerve paralysis caused by?

Answer 48

Fracture of humerus and stretching of the brachial plexus

Question 49

What is tibial nerve paralysis causes by?

Answer 49

A broken pelvis, which may damage the tibial portion of the sciatic nerve

Question 50

What is proprioception?

Answer 50

Position sense which is controlled by the somatic nervous system

Question 51

What is the autonomic nervous system?

Answer 51

- Unconsciously controlled motor nerves that supply cardiac msucle, visceral (smooth) and glandular tissue - Consist of sympathetic and parasympathetic

Question 52

What nerves are controlled by the parasympathetic system?

Answer 52

Cranial, vagus and sacral nerves

Question 53

What nerves are controlled by the sympathetic system?

Answer 53

Spinal nerves T1-L5, including the chain going up to the neck and the pelvis

Question 54

What are the effects of the sympathetic system?

Answer 54

- Increased heart and respiratory rate - Dilated pupils - Constricted blood vessels - Inhibited digestion

Question 55

What are the effects of the parasympathetic system?

Answer 55

- Decreased heart and respiratory rate - Constricted pupils - Dilated blood vessels - Stimulated digestion

Question 56

What is a reflex arc?

Answer 56

A protective involuntary response to noxious stimuli

Question 57

What are the clinical uses of using a reflex arc?

Answer 57

- Pedal (withdrawal reflex) - Tendon stretch - Perineal (anus twitches if touched) - Palpebral (tapping eyelid) - Corneal (touching corneal of the eye) - Pupillary light reflex (pen touch: dim light = pupils bigger, bright light = pupils smaller