Lab midterm Bio40B

Question 1

Components of a reflex arc:

Answer 1

1. Receptor
2. Sensory Neuron
3. Integration center
4. Motor Neuron
5. Effector

AKA…..R.S.I.M.E

Question 2

Somatic spinal reflexes:

Answer 2

1. Stretch reflexes
2. Crossed extensor reflexes
3. Superficial cord reflexes
4. Cranial nerve reflexes

Question 3

Longitudinal Fissure:

Answer 3

Divides the cerebral hemisphere into right and left

Question 4

Transverse Fissure

Answer 4

Divides cerebrum from the cerebellum

Question 5

Central Sulcus

Answer 5

Divides the frontal lobe from the parietal lobe

Question 6

Lateral Sulcus

Answer 6

Separates the temporal lobe from the frontal and part of the parietal lobe

Question 7

Parieto-occipital sulcus

Answer 7

divides the parietal lobe from the occipital lobe

Question 8

Protections of the spinal cord:

Answer 8

1. Vertebrae
2. Meninges: Dura mater; arachnoid mater; Pia mater
3. Cerebrospinal Fluid

Question 9

Two grooves run the length of the SC

Answer 9

• Posterior median sulcus

- Anterior median fissure

Question 10

White matter(SC)

Answer 10

• Composed of myelinated and unmyelinated axons
• Allows communication between SC and brain
• Classified by type: ascending fibers: descending fibers; commissural fibers

Question 11

Gray matter(SC): shaped like the letter H

Answer 11

• Dorsal horns: consist of interneurons
• Ventral and Lateral horns: contain cell bodies of motor neurons
• Gray commissure: contains central canal

Question 12

Ventral roots

Answer 12

arise from the anterior horn and contain motor fibers(efferent)

Question 13

Dorsal roots

Answer 13

arise from sensory neurons in the dorsal root ganglion and contain sensory fibers(afferent)

Question 14

Cervical plexus: C1-C5

Answer 14

includes phrenic nerve

Question 15

Brachial plexus: C5-T1

Answer 15

includes axillary nerve, Ulnar nerve, median nerve, radial nerve

Question 16

Lumbar plexus: L1-L4

Answer 16

femoral nerve

Question 17

Sacral plexus: L4-S4

Answer 17

Sciatic nerve

Question 18

Pupillary light reflex:

Answer 18

Tests for optic nerve II and III

Question 19

Eye layers

Answer 19

1. Fibrous layer
2. Vascular layer
3. Sensory layer; Retina

Question 20

Fibrous layer(eye)

Answer 20

Sclera and Cornea

Question 21

Vascular layer(eye)

Answer 21

Choroid, Ciliary body and Iris

Question 22

Sensory layer; Retina

Answer 22

Pigmented layer; Neural layer

Question 23

Ciliary muscle(eye)

Answer 23

changes lens thickness to allow light to be properly focused on the retina

Question 24

Vitreous humor in posterior segment(eye)

Answer 24

Jellylike, transmits light< maintain shape of eyeball and holds the retina in place

Question 25

Aqueous humor in Anterior segment(eye)

Answer 25

filled with liquid, replaced continuously, brings nutrients

Question 26

Sensory layer(Retina) contains photoreceptors:

Answer 26

1. Rods 2. Cones 3. Signals leave the retina toward the brain through the optic nerve

Question 27

What is the sclera?

Answer 27

White outer layer of eyeball. At the front of eye it is continuous with the cornea

Question 28

What is the cornea and what does it do?

Answer 28

Acts as outermost lens. The aperture

Question 29

What is the function of the Optic nerve?

Answer 29

Transfer visual information from retina to vision centers in brain via electrical impulses

Question 30

What does the Iris do?

Answer 30

responsible for controlling diameter and size of pupil and thus amount of light reaching retina. Eye color is defined by that of Iris

Question 31

What is the Pupil?

Answer 31

Light enters the eye through the pupil

Question 32

What is the function of the Ciliary muscle?

Answer 32

fibers that suspend the lens in position during accommodation, enabling changes in lens shape for light focusing

Question 33

What does the Lens do?

Answer 33

Helps to focus light and images on your retina

Question 34

What is the Vitreous humor?

Answer 34

transparent jellylike tissue filling the eyeball behind the lens

Question 35

Where is the blind spot located?

Answer 35

where the optic disc is located(aka the optic nerve head).

Question 36

What is the Retina?

Answer 36

Layer at back of eyeball containing cells that are sensitive to light and that trigger nerve impulses that pass via the optic nerve

Question 37

What is the function of the Tapetum?

Answer 37

retroreflector. reflex visible light back through the retina.

Question 38

Do humans have a Tapetum layer?

Answer 38

Humans do not have a Tapetum layer

Question 39

Which structure is made up of circular and radial smooth muscles?

Answer 39

Ciliary body

Question 40

The lens divides the eye into:

Answer 40

Anterior and Posterior chambers

Question 41

Choose the correct answer A. Cataract is when the lens becomes more opaque. B. Cataract is when the aqueous humor does not drain well

Answer 41

A

Question 42

Where is the origin of the Optic nerve?

Answer 42

Retina

Question 43

Lamellar or Pacinian corpuscles

Answer 43

responsible for sensitivity to vibrations and pressure

Question 44

Rods and cones. Highest concentration of these are located in:

Answer 44

The Macula

Question 45

The suspensory ligaments and ciliary muscle control the shape of the following structure:

Answer 45

Lens

Question 46

Monosynaptic reflexes:

Answer 46

Sensory neuron synapse directly on a motor neuron(no interneuron).

Question 47

Polysynaptic reflexes:

Answer 47

at least one interneuron between the sensory and motor neuron

Question 48

Ipsilateral reflexes:

Answer 48

A reflex response that effects the same side as the stimulus

Question 49

Contralateral reflexes:

Answer 49

A reflex that affects the opposite side of the body from the stimulus

Question 50

Consensual reflex:

Answer 50

Occurs on both sided of the body at the same time.

Question 51

Intersegmental reflex:

Answer 51

The integration occurs at different levels in the spinal cord.