Nervous System

Question 1

Functions of Nervous System

Answer 1

the function of the nervous system is to detect impulses from the senses; control center of the body

Question 2

Major Organs of Nervous System

Answer 2

Brain
Spinal Cord
Senses
Nerves

Question 3

Neurons and Neuroglia

Answer 3

Neurons (make up 10% of the nervous system)

Neuroglia (“nerve-glue”, make up 90% of the nervous system)

Question 4

Dendrite

Answer 4

receive the nerve impulses from the senses or another neuron

Question 5

Soma

Answer 5

body of the neuron that holds the nucleus

Question 6

Schwann Cells

Answer 6

wrap around axons of motor and sensory neurons to form the myelin sheath

Question 7

Node of Ranvier

Answer 7

impulses jump from node to node, which increase speed of impulse

Question 8

Myelin

Answer 8

insulates the axon. Produced by the Schwann cells

Question 9

Axon

Answer 9

passageway for nerve impulses after cell body; end in axon terminal

Question 10

Axon Terminal

Answer 10

the button-like endings of axons through which axons make contact with other nerve cells.

Question 11

CSF

Answer 11

The cerebrospinal fluid protects the brain by preventing the it from contacting the skull.
It also maintains the blood-brain barrier, which controls homeostasis for the brain and prevents infection.
The CSF is produced in spaces within the brain called ventricles. CSF is constantly being produced, circulated and reabsorbed within these ventricles.

Question 12

Cerebrum

Answer 12

Largest part of brain
Divided into 2 hemispheres
Outer cerebral cortex= “gray matter,” made of cell bodies & dendrites
Controls conscious activities
Inner cerebral medulla= “white matter,” made of myelinated axons

Question 13

Frontal Lobe

Answer 13

Voluntary movements (walking)
Reasoning & decision-making
Memory
Ability to predict consequences of actions
Planning
Verbal communication

Question 14

Parietal Lobe

Answer 14

The parietal lobe controls:
Sensations
Visual-spatial processing
Body position

Question 15

Occipital Lobe

Answer 15

The occipital lobe controls:

Visual processing- vision & memory of objects

Question 16

Temporal Lobe

Answer 16

The temporal lobe controls:
Memory
Comprehension & pronunciation of words
Sensations of smell and sound
Emotional association of memories

Question 17

Thalamus

Answer 17

2 bulb-shaped halves in the center of the brain

Relays sensory impulses to the cerebral cortex for processing and sorting

Question 18

Hypothalamus

Answer 18

Controls hormones released by pituitary gland (often called the “master endocrine gland”)
Responsible for autonomic processes (body temperature, hunger, sleep, thirst, blood volume, etc)

Question 19

Brainstem

Answer 19

Located between the cerebrum and spinal cord.

Question 20

Midbrain

Answer 20

Also known as mesencephalon
Relays info to cerebrum
Controls body movements and postures

Question 21

Pons

Answer 21

The Bridge!
Almost completely made of white matter that links cerebral cortex and cerebellum
Carries info from one side of brain to the other (why its called the bridge)
Central control of breathing

Question 22

Temporal Lobe

Answer 22

The temporal lobe controls:
Memory
Comprehension & pronunciation of words
Sensations of smell and sound
Emotional association of memories

Question 23

Cerebellum

Answer 23

Second largest part of brain
Near back of skull
Responsible for coordinating the movements directed by the cerebrum so that they are graceful and efficient
All involuntary movements
Aids in “muscle memory”

Question 24

Spinal Cord

Answer 24

Extends from the medulla oblongata
31 pairs of spinal nerves branch out from the spinal cord, connecting to all parts of the body
Relays impulses from the PNS to the brain
A cross section of the spinal cord has a “butterfly” of gray matter surrounded by white matter

Question 25

Mechanoreceptors (touch)

Answer 25

Mechanoreceptors are a type of somatosensory receptors which relay extracellular stimulus to intracellular signal transduction through mechanically gated ion channels.

Question 26

Thermoreceptors (temperature variations)

Answer 26

Thermoreceptors are free nerve endings that reside in the skin, liver, and skeletal muscles, and in the hypothalamus, with cold thermoreceptors 3.5 times more common than heat receptors.

Question 27

Pain receptors

Answer 27

A nociceptor (“pain receptor”) is a sensory neuron that responds to damaging or potentially damaging stimuli by sending “possible threat” signals to the spinal cord and the brain.

Question 28

Chemoreceptors (chemicals)

Answer 28

Chemoreceptors are specialized cell groups responsible for acquiring information about the chemical environment and subsequently conveying the information to neurons.

Question 29

Photoreceptors (light)

Answer 29

Photoreceptors are specialized cells for detecting light. They are composed of the outer nuclear layer that contains the cell nuclei, the inner segment that houses the cell machinery, and the outer segment that contains photosensitive pigment.

Question 30

Papillae

Answer 30

The tongue is filled with bumps called papillae. Many of these papillae contain taste buds, which contain chemoreceptors.

Question 31

Malleus

Answer 31

hammer

Question 32

Incus

Answer 32

anvil

Question 33

Stapes

Answer 33

stirrup

Question 34

Cochlea

Answer 34

boney snail-shaped structure containing membranes filled with fluid

Question 35

Cornea

Answer 35

allows light into the eye

Question 36

Pupil

Answer 36

muscles regulate the amount of light entering the eye

Question 37

Iris

Answer 37

works with pupil to regulate the amount of light entering the eye

Question 38

Retina

Answer 38

located in the back of the eye, contains thousands of photoreceptors

Question 39

Lens

Answer 39

semi-solid disc that directs light waves towards the retina

Question 40

Farsighted vs Nearsighted

Answer 40

farsighted- can’t see near

nearsighted- can’t see far