Special Sense Organs Part 1 Flashcards Preview

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Flashcards in Special Sense Organs Part 1 Deck (33)
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1

T/F: The special sense organ of vision, the eye, is derived from both the ectoderm and the mesoderm.

True

2

What are the fibrous coats of the eyes derived from?

mesoderm

3

What parts of the eye are derived from the ectoderm?>

lens, retina, cornea, and pigmented layers

4

What 3 coats make up the eye?

Fibrous tunic (outermost), vascular tunic, and the nervous tunic (retina)

5

Which coat of the eye is made up of the sclera and cornea?

fibrous tunic

6

What is the term for the thick, dense, firm, opaque, white part of the eye?

sclera

7

What structure maintains the shape of the eye if internal pressure is increased?

sclera

8

What kind of structures pass through the many openings of the sclera?

blood vessels and neurons

9

T/F: extraocular muscles attach to the sclera.

True

10

T/F: posteriorly, the sclera transitions to the cornea at the limbus and is lined with conjunctiva.

False; this occurs anteriorly

11

What structure is the sclera continuous with posteriorly?

fibrous sheath that covers CN II

12

What is the anterior part of the fibrous tunic?.

cornea

13

T/F:The cornea is transparent, concave to the anterior, and is the primary refractory part of the eyeball.

False; should say convex to the anterior

14

What are the 5 layers of the cornea from anterior to posterior?

Corneal epithelium, Anterior limiting lamina, Substantia propria, Posterior limiting lamina, and Endothelium (CASPE)

15

Which layer of the cornea is continuous with the conjunctiva?

Corneal epithelium

16

What layer of the cornea covers the inside surface of the cornea and lines the iridocorneal layer?

Endothelium

17

What is the largest part of the cornea?

Substantia propria

18

What are the 3 parts of the Vascular Tunic?

choroid, ciliary body, and iris

19

T/F: the choroid is thin with a poor blood supply.

False; thin with a rich blood supply

20

T/F: the blood vessels of the choroid are heavily supplied by autonomic, vasomotor fibers and may have a cooling effect.

True

21

The choroid is loosely attached to the sclera except for where?

choroid is firmly attached to the sclera where the optic nerve pierces it

22

What purpose does the dark pigmentation of the choroid serve?

helps limit the passage of light both through the sclera to the retina and through the retina to the sclera

23

What is the ciliary body continuous to the anterior? to the posterior?

iris;
choroid

24

T/F: the ciliary body serves to suspend the lens and produce aqueous fluid found in the anterior segment of the eye?

True

25

T/F: the ciliary body may produce some glycosaminoglycans of the vitrous body.

True

26

Where is the ciliary muscle contained?

ciliary body

27

What is the function of the ciliary muscle?

contraction allows the lens to become more convex, allowing for near vision

28

What is the colored part of the eye which ranges from light blue to dark brown?

Iris

29

What divides the anterior segment of the eye into anterior and posterior chambers?

Iris

30

What muscles does the Iris consist of?

sphincter pupillae and dilator pupillae