Integumentary System

Question 1

Epidermis?

Answer 1

• Superficial, thinner portion composed of epithelial tissue.

Question 2

Dermis?

Answer 2

• Deeper, thicker portion, composed of dense irregular connective tissue.

Question 3

Hypodermis?

Answer 3

Deep to dermis but not part of skin is subcutaneous (hypodermis).

Question 4

Epidermis contains 4 types of cells?

Answer 4

• Keratinocytes: Produce keratin. Protects cells, maintains elasticity,
• Melanocytes: Produce melanin. Melanin protects skin by shielding from the sun.
• Intraepidermal macrophages- Immune response.
• Tactile epithelial cells: Detect touch sensations.

Question 5

Lamellar granules?

Answer 5

Present in keratinocyte.
Release lipid rich secretion that acts as a water repellent sent, holding back loss of water.

Question 6

Newly formed cells in the stratum basale are?

Answer 6

Slowly pushed to surface.

Question 7

More and more kertain accumulation is called?

Answer 7

Keratinisation.

Question 8

Epidermis has 4 layers?

Answer 8

• Stratum corneum- Most superficial layer.
• Stratum granulosum- Keratinocytes undergo apoptosis here.
• Stratum spinosum- Provides strength and flexibility.
• Stratum basale- Deepest layer.

Palms and soles have one extra layer- Stratum Lucidum.

Question 9

Dermis?

Answer 9

• Superficial layer is called papillary layer.
• Consists of:
  Areolar (contains elastic fibres).
  Dermal papillae with though receptors.
  Capillary loops and sensory neurons.

Question 10

Meissner corpuscle?

Answer 10

Type of touch receptor.
Found in dermal papillae.

Question 11

Deepest part of dermis is called?

Answer 11

• Reticular layer.
• Consists of:
  Dense irregular.
  Elastic and collagen.
• Function: Provide strength and flexibility.

Question 12

Accessory structures of skin are?

Answer 12

• Hair.
• Nails.
• Glands.

Question 13

Associated with hair are?

Answer 13

• Bundles of smooth muscle called arrector pili.
• Sebaceous glands or oil glands.

Question 14

Colour of hair is due to?

Answer 14

Melanin.
- Grey hair occurs with decline in melanin.
- White hair results from accumulation of air bubbles in the hair shaft.

Question 15

Glands?

Answer 15

Single or groups of epithelial cells that secrete a substance.

Question 16

Sebaceous glands?

Answer 16

• Usually connected to hair follicles.
• Produce sebum which moistens hair and waterproofs skin.

Question 17

Ceruminous glands?

Answer 17

Reduces risk of bacterial and fungal infection.
Located in ear canal, earwax.

Question 18

Sudoriferous glands?

Answer 18

Secrete water and salt as sweat.
Helps lower body temperature.

Question 19

Two types of sudoriferous glands?

Answer 19

• Apocrine: Found mainly in skin of armpit, groin etc.
• Eccrine: Most prevalent. Found in forehead, palms and soles.

Question 20

Cell division of nail matrix cells produces?

Answer 20

New nails.

Question 21

5 major functions of skin?

Answer 21

1. Body temperature regulation- Release sweat to lower temperature.

Question 22

2.?

Answer 22

Protection.
Keratin protects tissue form microbes and heat etc.
Lipids released by lamellar granules inhibit evaporation of water from skin surface.

Question 23

3.?

Answer 23

Cutaneous sensations.
Touch, pressure, vibration and pain.

Question 24

4.?

Answer 24

Excretion and absorption.
Skin has a small ability to absorb and excrete chemicals and toxins.

Question 25

5.?

Answer 25

Synthesis if vitamin d. Exposing skin to UV radiation activates vitamin d.

Question 26

When there is damage to skin, cells begin to heal to restore homeostasis?

Answer 26

- Epidermal- Involves damage to epidermis only and stratum basale move into wound to reproduce and create new layers. - Deep wound healing- Extends to epidermis and lower. Fibroblast lay down collagen and forms scar tissue.

Question 27

Aging and integumentary system?

Answer 27

- Collagen fibres decrease in number and stiffen. - Elastic fibres lose elasticity, thicken into clumps. - Fibroblasts which produce both of the above decreasing number known as wrinkles. - Less sebum and sweat. - Hair thins may stop going. - Slower skin healing.

Question 28

3 common forms of skin cancer?

Answer 28

- Basal cell carcinoma. Tumours in stratum basale, rarely spread. - Squamous cell carcinoma. Arise from stratum spinosum and may spread. - Malignant melanoma. Arise from melanocytes.

Question 29

Exposure to UV radiation may?

Answer 29

Produce photosensitivity, reaction of skin.

Question 30

Burns?

Answer 30

1st- Only epidermis and mild pain, no blisters. 2nd- Damage epidermis and part of dermis, can cause blisters. 3rd- Damage epidermis and dermis and subcutaneous layer, most skin functions are lost.

Question 31

Which is the only layer of the epidermis that contains stem cells capable of continued cell division?

Answer 31

Stratum basale.

Question 32

Cuticle of the nail consists of?

Answer 32

Stratum corneum.

Question 33

Arrector pilli contract in response to?

Answer 33

Stress like cold or fright.