LESSON 19 (Hair, Sweat and Nails)

Question 1

what are Pili?

Answer 1

• aka hairs
• flexible strands of dead, keratinized cells produced by hair follicles

Question 2

what is the function of hair?

Answer 2

• warning of parasites on your skin
• insulating heat
• protects your head against physical trauma
• shields skin from sunlight

Question 3

what is the Shaft?

Answer 3

the main region of the a hair tht projects from the skin

Question 4

what is the Root?

Answer 4

the hair part that is EMBEDDED in the skin

Question 6

How are hair pigments made?

Answer 6

By melanocytes at the base of the hair follicle and then transferred to the cortical cells

Question 7

what is the structure of hair follicles?

Answer 7

folds down from the epidermis into the dermis and occasionally into the hypodermis

Question 8

what are hair bulb surrounded by?

Answer 8

sensory nerve endings called Hair Follicle Receptors or Root Hair Plexus

Question 9

What are the wall of hair follicle compose of?

Answer 9

• Peripheral Connective Tissue Sheath (thick basement membrane from the dermis)
• Epithelial Root Sheath (derived from the epidermis)

Question 10

What is the hair matrix?

Answer 10

a group of actively dividing cells that produce the hair which is located within the hair bulb

Question 11

What are Arrector Pili Muscle?

Answer 11

bundles of smooth muscle and which causes hairs to stand upright when contraction occurs

Question 12

What is Hair Papilla?

Answer 12

a dermal tissue that contains a know of capillaries that supplies nutrients for hair growth

Question 13

what are Vellus Hairs?

Answer 13

hairs that are pale, fine and short hairs (PEACH FUZZ)

Question 14

what are Terminal Hairs?

Answer 14

hairs that are longer, coarser and thick (PUBIC HAIR)

Question 15

what is Alopecia

Answer 15

when hair is not replaced as quickly as it is lost. Leading to hair thinning and balding

Question 16

what does Sebaceous Gland secrete?

Answer 16

Sebum (grease)

Question 17

Function of Sebaceous Glands

Answer 17

functions as a Holcrine
- secreting their product into a hair follicle or to a pore on the surface of the skin

Question 18

Function of Sebum

Answer 18

• to soften and lubricate the hair and skin
• slows water loss
• bactericidal

Question 19

What are Eccrine

Answer 19

• aka MEROCRINE
• sweat glands that produce true sweat
• abundant on the palms of the hands, soles of the feet, and forehead

Question 20

which area can you find the Apocrine Sweat Glands?

Answer 20

Axillary (ARMPIT) and anogenital areas

Question 21

What does Apocrine Sweat Glands produce

Answer 21

fat and protein-rich true sweat,

Question 22

what are Ceruminous Glands and where can you find it

Answer 22

modified Apocrine Swear Glands which can be found lining the ear canal that secrete earwax (cerumen)

Question 23

what are Mammary Glands?

Answer 23

also a modified Apocrine Sweat Glands that secrete milk

Question 24

What the purpose of nails?

Answer 24

it forms a protective covering on the dorsal side of the distal finger or toe

Question 25

what are nails made up of?

Answer 25

- hard keratin - have a free edge, nail body that is attached to the skin and a root embedded in the skin

Question 26

what is the Nail Matrix responsible for and where is it located?

Answer 26

- nail matrix contains dividing cells therefore responsible for nail growth - nail matrix can be found within the proximal part of the nail bed

Question 27

what is the Free Edge on the fingernails?

Answer 27

it extends past the finger or toes

Question 28

What is the Proximal Nail Fold and Lateral Nail Fold of the fingernails?

Answer 28

where the skin covers over the edges of the nail

Question 29

What is the Luna (little moon) part of the fingernails?

Answer 29

the thick, white part of the nail, immediately distal to the eponychium

Question 30

What is Eponychium (Cuticle) part of the fingernails?

Answer 30

the stratum corneum of the epidermis at the proximal nail fold

Question 31

what part is the Nail Root on the fingernails?

Answer 31

the portion that is not visible

Question 32

what part is the Nail Body on the fingernails?

Answer 32

the visible portion of the nail

Question 33

what part is the Nail Bed on the fingertip?

Answer 33

the skin below the nail body

Question 34

what is the function of Hyponychium

Answer 34

secures the nail to the fingertip

Question 35

what is the Distal Phalanx?

Answer 35

the finger or toe bone under the nail