Histology 🔬

Question 1

Histological structure of The cerebellum

Answer 1

• It has arborization like the leaves of a tree called “ Folia”.

Question 2

what does Each folium consists of?

Answer 2

• central core (inner medulla) of white matter (pale by H & E).
• periphral or outer cortex of gray matter (dark by H & E).

Question 3

Cerebellar cortex consists of three layers from outside inwards, explain

Answer 3

Cerebellar cortex consists of three layers from outside inwards:
- Molecular layer.
- Purkinje cell layer.
- Granular (nuclear) layer.

Question 4

what are Purkinje cel. of cerebellum?

Answer 4

• Large pyriform arranged in one row away from each other

Question 5

Axon of purkinje cell of cerebellum

Answer 5

• Axon of Purkinje cell enter the white matter to end in deep cerebellar nuclei & vestibular nuclei.

Question 6

what are Layers of cerebral cortex?

Answer 6

I. Plexiform (molecular) layer.
II. Outer granular layer.
III. Pyramidal cell layer.
IV. Inner granular layer.
V. Ganglionic layer.
VI. Multiform cell layer.

Question 7

Stains of Cerebral cortex

Answer 7

Silver stain, H & E

Question 8

what does the brain stem consist of?

Answer 8

PPT

Question 9

Other names of inferior pons level

Answer 9

• level of facial colliculus

Question 10

Other names of middle pons level

Answer 10

• level of trigeminal nuclei

Question 11

Other names of superior pons level

Answer 11

level of the four lemnisci

Question 12

Other names of inferior midbrain level

Answer 12

• Level of inferior colliculus
• Level of trochlear nerve nucleus
• Level of decussation of superior cerebellar peduncles

Question 13

Other names of superior midbrain level

Answer 13

• Level of superior colliculus
• Level of red nucleus
• Level of occulomotor nerve nucleus

Question 14

Structure of Pacinian corpuscle

Answer 14

• Thin C.T. capsule.
• Concentric layers of modified schwann cells.
• The naked nerve )non- myelinated( is seen in the center of the corpuscle.

Question 15

Structure of Muscle spindle

Answer 15

Capsulated structure between the skeletal muscle fibers and is formed of:

• Capsule and sub-capsular space.
• Intrafusal muscle fibers.

Question 16

Structure of Corneal epithelium

Answer 16

• ## stratified squamous non- keratinized

Question 17

Structure of Substantia propria

Answer 17

(main thickness): parallel collagenous bundles and C.T. cells

Question 18

Structure of Iris

Answer 18

PPT

Question 19

what is Ciliray body formed of?

Answer 19

• formed of the ciliary muscles which are formed of smooth muscle fibers that run in different directions.

Question 20

Ciliary processes

Answer 20

• appear as ridge-like processes projecting towards the posterior chamber of the eye

Question 21

Structure of Ciliary processes

Answer 21

The ciliary processes are formed of:

• C.T. core
• Ciliary epitheliuim: Formed of two layers of cubical epithelial cells one is non
  pigmented and the other is richly pigmented with melanin pigment.

Question 22

Structure of eyelid

Answer 22

• The external surface is covered with thin skin.
• Mebomian gland is seen in the tarsal plate.
• The internal surface is covered with palpebral conjunctiva.

Question 23

where do Cells forming organ of Corti lie?

Answer 23

• on the basilar membrane inside the cochlear duct.

Question 24

what covers organ of corti?

Answer 24

• Tectorial membrane