Simplier Quiz 2

Question 1

1. Epithelial Tissues and Cell Types

Answer 1

Simple Epithelia:

Cuboidal: Cube-shaped cells, found in glands.
Columnar: Tall, column-like cells, often involved in absorption (e.g., intestines).
Pseudostratified: Appears stratified but is a single layer with nuclei at different heights.
Stratified Epithelia:

Stratified Squamous: Multiple layers; protection (e.g., skin).
Keratinized Stratified Squamous: Tough, waterproof (found in skin).
Stratified Cuboidal/Columnar: Rare, found in certain ducts like sweat glands.

Question 2

2. Features of the Epidermis

Answer 2

Layers of the epidermis (from deep to surface):
Stratum Basale: Deepest layer, where cells divide.
Stratum Spinosum: Cells begin keratinization.
Stratum Lucidum: Dead cell layer (in thick skin only).
Stratum Corneum: Outermost, keratinized layer.

“Before Sunshine Lies Cells” (Basale, Spinosum, Lucidum, Corneum). (BuduSsy LiCk my Coochie)

Question 3

3. Features of the Dermis

Answer 3

Derived from the dermatome.
Consists mostly of collagen.
Dermal bones: Formed via intramembranous ossification.
Key feature: The dermis is the connective tissue layer beneath the epidermis, providing strength and elasticity.

Question 4

4. Epidermal Invagination vs. Dermal Evagination

Answer 4

Epidermal invagination: Structures like hair, feathers, and glands are formed by the epidermis dipping down into the dermis.

Dermal evagination: Structures like scales form by the dermis pushing up into the epidermis.

Remember: “Invagination goes in, evagination goes up.”

Question 5

5. Types of Bone

Answer 5

Lamellar Bone: Organized, slow-growing, and mature bone.
Non-lamellar Bone: Disorganized, found in young or fast-growing bones.

Question 6

6. Intramembranous vs. Endochondral Ossification

Answer 6

Intramembranous: Bone forms directly from mesenchymal tissue (e.g., skull bones).

Endochondral: Bone forms from a cartilage model (e.g., long bones like the femur).

Question 7

Skull Bones and Evolution

Answer 7

Three Major Divisions:

Splanchnocranium: Supports gills and respiratory structures.

Chondrocranium: Supports the brain.

Dermatocranium: Forms the outer casing (skull roof).

Question 8

8. Embryonic Derivation of Vertebrae

Answer 8

Derived from somites (specifically, the sclerotome part).

Steps:
Sclerotome cells migrate around the notochord.
Form the perichordal ring.
Eventually form the vertebrae.

Question 9

9. Types of Vertebrae

Answer 9

Acoelous: Flat on both sides, limited flexibility.
Opisthocoelous: Convex front, concave back; allows more movement.
Heterocoelous: Saddle-shaped, allows more flexibility.

Question 10

10. Regionalization of Vertebrae

Answer 10

Vertebrae vary in shape depending on location (cervical, thoracic, lumbar), affecting movement and flexibility.

Question 11

11. Rib Parts and Function

Answer 11

Parts: Head (attaches to vertebra), neck, tubercle, and shaft.

Function: Support, muscle attachment, and protection of visceral organs.

Question 12

12. Limb Evolution and Fin Parts

Answer 12

Fin Rays:
Ceratotrichia: Keratin-based in sharks and rays.
Lepidotrichia: Ossified/cartilaginous in bony fish.

Limb Divisions:
Stylopod: Upper arm/thigh.
Zeugopod: Forearm/shank.
Autopod: Hands/feet.

Question 13

13. Tetrapod Limb Development

Answer 13

Autopod: Developed mostly from the postaxial (back side) of the zeugopod.

Question 14

14. Pelvic and Pectoral Girdles

Answer 14

Pelvic Girdle: Always endoskeletal, attaches to the vertebral column via the ilium.

Pectoral Girdle: Muscular sling attaching it to the axial skeleton.

Question 15

15. Grades of Locomotion

Answer 15

Unguligrade: Walks on the tips of toes (e.g., horses).
Digitigrade: Walks on toes (e.g., dogs).
Plantigrade: Walks on the soles of feet (e.g., humans).