PRACTICE QUIZ UNIT 11

Question 1

Another name for the subcutaneous layer

Answer 1

Hypodermis

Question 2

Layer composed of keratinized stratified squamous epithelium

Answer 2

Epidermis

Question 3

Pigment secreted by specialized cells in skin absorbing UV

Answer 3

Melanin

Question 4

Layer of epidermis composed of single row cuboidal or columnar keratinocytes

Answer 4

Stratum basale

Question 5

Layer of skin composed of mainly dense irregular connective tissue containing collagen and elastic fibres

Answer 5

Dermis

Question 6

Sweat gland function

Answer 6

Important role in thermoregulation

Question 7

Stratum Basale (2)

Answer 7

• Single layer of cuboidal-shaped epithelial cells that undergo cell division.
• Two other cell types: Merkel Cells (touch receptors) and melanocytes (melanin).

Question 8

Stratum Spinosum (4)

Answer 8

-Eight to ten layers of spiny-looking keratinocytes.
- Look spiny due to protruding cell processes that join cells via desmosomes.
- Langerhans cells also present (function as macrophages).
- Keratinocytes produce keratin and release a water-repelling glycolipid that helps
prevent water loss from the body, making the skin relatively waterproof.

Question 9

Stratum Granulosum (2)

Answer 9

• Grainy appearance, 3-5 layers of cells become flatter, cell membranes thicken, and make large amounts of fibrous keratin and keratohyalin, which accumulates as granules within the cells.
• Cell organelles disintegrate as the cells die.

Question 10

Stratum Lucidum (3)

Answer 10

• Translucent layer found only in the thick skin of the palms, soles, and digits
  . - Keratinocytes are dead and flattened.
• Cells packed with eleiden, a clear protein, derived from keratohyalin, which
  gives them their transparent (lucid) appearance and provides a barrier to water.

Question 11

Stratum Corneum (3)

Answer 11

• 15-30 layers of dead cells displaying increased keratinization.
• Prevents penetration of microbes, dehydration of underlying tissues, and
  mechanical protection against abrasion.
• Cells shed periodically and replaced by cells pushed up from the layer below.

Question 12

Eccrine Sweat Gland (3):

Answer 12

• Produces a hypotonic sweat for thermoregulation.
• Found all over the skin’s surface, but especially abundant on the palms of the
  hand, the soles of the feet, and the forehead.
• They are coiled glands lying deep in the dermis, with the duct rising to a pore on
  the skin surface, where the sweat is released.

Question 13

Apocrine Sweat Gland (3)

Answer 13

• Usually associated with hair follicles in densely hairy areas, such as the armpits and anogenital regions.
• Larger than eccrine sweat glands and lie deeper in the dermis, with the duct normally emptying into the hair follicle.
• In addition to water and salts, apocrine sweat includes organic compounds that make the sweat thicker and subject to bacterial decomposition and subsequent smell.