Brain 1: Spinal cord physiology and brain development and coverings

Question 0

2 main sensory tracts

Answer 0

Spinothalamic tract:

Posterior column:

Question 1

2 main function of spinal cord

Answer 1

1. Propagates nerve impulses (in white matter)

2. Integrates information (in grey matter)

Question 2

What does spinothalamic tract do

Answer 2

Conveys nerve impulses for sensing pain, temperature, itch, tickle and deep pressure

Question 3

What is two tracts of posterior column?

Answer 3

Facilicus (leg) and Cunneate fascilicus (arm)

Question 4

What does posterior column do?

Answer 4

conveys nerve impulses for touch, light pressure, vibration and conscious proprioception

Question 5

What is conscious proprioception

Answer 5

The awareness of the positions and movements of muscles, tendons and joints

Question 6

what is 2 main motor tracts

Answer 6

Direct pathways (lateral corticospinal tract, anterior corticospinal tract, corticobulbar tract)
corti- cortex,
spinal -spinal, efferent, motor
bulbar - brainstem

Indirect pathways (rubrospinal, tectospinal, vestibulospinal, lateral reticulospinal, medial reticulospinal tracts)

Question 7

What is direct pathways of motor tracts

Answer 7

nerve impulses originate in cerebral cortex
cause voluntary movements of skeletal mm
brainstem is considered traveling down

Question 8

what do indirect pathways of motor tracts do

Answer 8

nerve impulses originate in brain stem
cause automatic movements
helps coordinate body movements with visual stimuli
maintain muscle tone

Question 9

what is reflex

Answer 9

a fast involuntary unplanned sequence of actions that occurs in response to a particular stimulus
can be in born or learned

Question 10

4 different reflexes

Answer 10

spinal reflex
cranial reflex
somatic reflex
automatic (visceral) reflexes

Question 11

spinal reflex is

Answer 11

when integration happens in gray matter in Spinal cord

Question 12

cranial reflex is

Answer 12

when integration happens in brainstem

Question 13

somatic reflex is

Answer 13

involves contraction of skeletal muscle

Question 14

autonomic (visceral) reflexes is

Answer 14

not usually consciously perceived

Invovled responses of smooth mm, cardiac mm and glands

Question 15

Four somatic spinal reflexes

Answer 15

1. The stretch reflex
2. Tendon reflex
3. Flexor (withdrawal reflex)
4. crossed extensor reflex

Question 16

Stretch reflex

Answer 16

Sensor receptor: muscle spindle
Mono synapse
Reciprocal innervation: yes
ipsilateral reflex
intersegmental: no

Question 17

Tendon reflex

Answer 17

Sensory receptor: G.T.O
Poly synapses
Reciprocal innervation: yes
Ipsilateral reflex
Intersegmental: No

Question 18

Flexor (withdrawal) reflex

Answer 18

Sensory receptor: n/a
Poly synapses
Reciprocal innervation: Yes
Ipsilateral reflex
intersegmental: Yes

Question 19

Cross extensor reflex

Answer 19

Sensory receptor: n/a
poly synapses
reciprocal innervation: yes
Intersegmental: yes

Question 20

what do brain and spinal cord develop from

Answer 20

ectoderm, arranged in a neural tube

Question 21

Three primary brain vesicles

Answer 21

Prosencephalon (forebrain)
Mesencephalon (midbrain)
Rhombencephalon (hindbrain)
3-4 week embryo

Question 22

5 secondary brain vesicles

Answer 22

5 week embryo
Prosencephalon divides to Telencephalon and Dienephalon
Mesencephalon stays as Mesencephalon
Rhombencephalon divides to Metencephalon and Myelencephalon

Question 23

Adult brain structure (walls and Cavities)

Answer 23

5 week embryo
Telencephalon becomes wall: Cerebrum, Cavities: lateral ventricles
Diencephalon becomes wall: Thalamus, hypothalamus and epithalamus, Cavities: Third ventricle
Mesencephalon becomes wall: Midbrain, cavities: Aqueduct of the midbrain
Metencephalon becomes wall: pons and cerebellum, cavities: upper part of forth ventricle
Myelencephalon becomes wall: Medulla oblongata, cavities: lower part of forth ventricle

Question 24

what does brain stem have

Answer 24

Continuous with spinal cord
medulla oblongata
pons
midbrain

Question 25

Where is cerebellum located?

Answer 25

posterior to brain stem

Question 26

what and where is diencephalon

Answer 26

superior to brain stem
Thalamus
Hypothalamus
epithalamus

Question 27

Where and what is cerebrum

Answer 27

largest part of the brain

sits on diencephalon

Question 28

protective coverings of the brain

Answer 28

cranium and cranial meninges surround and protect the brain

cranial meninges - continuous with the spinal meninges (Dura mater, arachnoid mater and pia mater)

Question 29

What is missing from spinal cord structure

Answer 29

no epidural space around brain

Question 30

Dura mater of the brain

Answer 30

outer meningeal layer made up of periosteal layer (external) and meningeal layer (internal). These 2 layers are fused together except where they separate to enclose the dural venous sinuses

Question 31

what is Dural venous sinuse

Answer 31

Endothelial-lined venous channels

Drain blood from the brain and deliver it into internal jugular veins

Question 32

3 extensions of dura mater

Answer 32

1. Falx cerebri: separates the 2 hemispheres of the cerebrum
2. Falx cerebelli: separates the 2 hemisphere of cerebellum
   3: Tentonium cerebelli: Separates the cerebrum from the cerebellum

Question 33

Blood flows to brain mainly via

Answer 33

internal carotid, vertebral arteries

Question 34

Blood flows out of brain via

Answer 34

the dural venous sinuses which drain into the internal jugular veins