Lab 8

Question 1

Central Nervous System (CNS)

Answer 1

which includes the brain and spinal cord occupying the dorsal body cavity.

Question 2

Peripheral Nervous System (PNS)

Answer 2

which consists mainly of the nerves which extend from

the brain and spinal cord, the cranial and spinal nerves.

Question 3

3 basic functions of NS

Answer 3

Sensory

• Sensory receptors detect internal and external stimuli
• sensory information is carried to the brain and spinal cord through cranial and spinal nerves.

Integrative
-The brain and spinal cord process, integrate and coordinate this incoming sensory information to formulate an appropriate response

Motor
-motor response is initiated by activating effector organs (muscles and glands) through cranial and spinal nerves.

Question 4

CNS 3 main protective structures

Answer 4

• Skull/Vertebral Column: a bony outer covering
• Meninges: three layers of membrane called
• Cerebrospinal fluid: watery fluid

Question 5

Skull and Vertebral Column

Answer 5

• sutures: immovable joints that join together bone
- All the bones of the adult skull
- except the mandible (lower jaw) & three small bones of the middle ear
•cerebrum is divided up into various regions or lobes
•lobes are named after the bones of the skull which overlie the brain
• Foramina - small holes
• Foramen magnum - large hole at its base
• vertebral column is composed of 33 vertebrae
• Vertebral foramen: each vertebra has a large hole, the vertebral foramen, through which the spinal cord passes.

Question 6

several small holes in skull through which many of the cranial nerves exit

Answer 6

foramina

Question 7

large hole at skull base through which the spinal cord passes as it enters the vertebral column

Answer 7

foramen magnum

Question 8

each vertebra has a large hole through which the spinal cord passes.

Answer 8

vertebral foramen

Question 9

3 layers of connective tissue in brain

Answer 9

Called meninges (singular: meninx):

1. dura mater
   
   • periosteal dura mater
   • meningeal dura mater
2. arachnoid mater
3. pia mater

Question 10

dura mater

Answer 10

• outermost meninx
• 2 layers: periosteal dura mater, meningeal dura mater
• The dural layers are fused together except where they separate under the cranium to form dural venous sinuses (eg. superior sagittal sinus) that collect venous blood from the brain and transfer it into the internal jugular veins.
• The spinal cord does not have a periosteal dura mater layer.
• epidural space: between the wall of the bony vertebral foramen and the spinal dura mater, filled with fatty tissue for cushioning.

Question 11

periosteal dura mater,

Answer 11

-closely attached to the inner surface of the bones of the skull

Question 12

meningeal dura mater

Answer 12

• forms the actual external covering over the brain
• sends one extension down between the cerebrum and cerebellum, and another between the two cerebral hemispheres (FN: anchor the brain inside the cranial cavity)

Question 13

arachnoid mater

Answer 13

• middle layer of the meninges
• filmy, cobweb like material with spider-like extension
• Beneath the arachnoid mater is a wide separation called the subarachnoid space

Question 14

pia mater

Answer 14

• innermost meninx
• very delicate
• highly vascularized membrane composed of areolar connective tissue
• adheres closely to the surface contours of the brain and spinal cord and dips deeply into the grooves
• not possible to separate the pia mater from the surface of the brain and spinal cord.
• anchor the spinal cord to the dura mater at regular intervals, limiting sideways movement of the cord.

Question 15

epidural space

Answer 15

between the wall of the bony vertebral foramen and the spinal dura mater, filled with fatty tissue for cushioning.

Question 16

subarachnoid space

Answer 16

contains cerebrospinal fluid and also the largest blood vessels serving the brain

between Pia & arannoid

Question 17

Cerebrospinal Fluid

Answer 17

• watery fluid with a composition similar to blood plasma and interstitial fluid
• fills the four ventricles of the brain and the central canal
• FUNCTION: as a cushion for the entire central nervous system, protecting the soft tissue from jolts and blows
• continuously produced by capillaries in the choroid plexuses found in the roof of each ventricle.
• CFS produced and drained at a constant rate
• in subarachnoid space, CSF is absorbed by the arachnoid villi

Question 18

CSF continuously produced by capillaries in the ______ found in the roof of each ventricle

Answer 18

choroid plexuses

Question 19

____ knobby projections of the arachnoid mater, to enter the venous blood in the dural sinuses. CSF is absorbed by this in the subarachnoid space

removes CSF

Answer 19

arachnoid villis

Question 20

List ventricles and connentions

Answer 20

• lateral ventricles, two large cavities filled with cerebrospinal fluid (numbered one and two)
• third ventricle can be seen as a shallow depression surrounding the thalamus, an oval mass beneath the lateral ventricle
• fourth ventricle, a triangular space between the pons and the cerebellum
• cerebral aqueduct: connects 3 to 4
• corpus callosum: forms an arch above the lateral ventricles
• central canal of the spinal cord: continuous with 4th ventricle

Question 21

What is hydrocephalus

Answer 21

is a condition in which an accumulation of cerebrospinal fluid (CSF) occurs within the brain. This typically causes increased pressure inside the skull.

A build up of cerebrospinal fluid occurs within the ventricles of the brain

Question 22

What is meningitis?

Answer 22

is an inflammation (swelling) of the protective membranes covering the brain and spinal cord. A bacterial or viral infection of the fluid surrounding the brain and spinal cord usually causes the swelling.

Question 23

What’s the largest portion of the brain?

Surface is highly convoluted with?

Answer 23

cerebrum

gyri (singular gyrus) = fold/ridges/elevations
sulci (singular sulcus) = grooves/depressions
fissures = deeper grooves

Question 24

separates the cerebrum into right and left cerebral hemispheres

Answer 24

longitudinal fissure

Question 25

a structure composed of nerve fibers which conduct impulses between the two hemispheres of the cerebrum.

Answer 25

corpus callosum

Question 26

cerebellum

Answer 26

- concerned with the involuntary coordination of skeletal muscle activity and the control of balance and equilibrium. - outer cortex made up of gray matter - inner region of white matter

Question 27

midbrain

Answer 27

is the topmost part of the brainstem, the connection central between the brain and the spinal cord

Question 28

- four rounded prominences on the dorsal midbrain surface. - The superior pair are visual reflex centers that coordinate head and eye movements when viewing a moving object. - The inferior pair are involved in the pathway of sound from the hearing receptors of the ear to the sensory cortex and also turning of the head towards sound in the startle reflex.

Answer 28

corpora quadrigemina

Question 29

medulla oblongata

Answer 29

contains many vital autonomic centers involved in the control of heart rate, respiratory rate, and blood pressure

Question 30

pons

Answer 30

pons = bridge | connect parts of the cerebellum and the medulla with the cerebrum.

Question 31

crossover point for the major motor tract descending from the cerebrum to the spinal cord

Answer 31

pyramids

Question 32

insula

Answer 32

fifth lobe deep within the lateral sulcus and is not visible unless parts of the other lobes are removed.

Question 33

precentral gyrus:

Answer 33

contains the primary motor area which is responsible for voluntary movement of skeletal muscle.

Question 34

postcentral gyrus:

Answer 34

contains the primary sensory area which receives information from sensory receptors for pressure, pain and temperature

Question 35

thalamus

Answer 35

important relay station for sensory impulses passing upward to the cerebral cortex. relay station for sensory impulses (hearing, sight, eveything but sence of smell)

Question 36

Hypothalamus

Answer 36

FUNCTION: regulate bod temp, control appitite, emotions like fear/rage, stores some hormones that are produced in pituitary gland. Produces hormones to control pituitary gland. Basically the master of the pituitary gland. involved in many vital processes such as regulating body temperature, water balance, appetite, and emotions such as fear and rage. It also regulates the release of hormones from the pituitary gland.

Question 37

thalamus + hypothalamus =

Answer 37

diencephalon

Question 38

The point at which these nerves emerge from the surface of the brain is referred to as their ________the area within the brain where the nerve fibers actually begin is known as their______.

Answer 38

superficial origin deep origin