Exam 2 Ch. 5 Study Guide Questions Flashcards
Name 3 types of epidermal cells and their functions.
Stratified squamous epithelium tissue including:
1. Keratinocytes - make keratin, waterproofing and strengthening protein 2. Melanocytes - make melanin, pigment protein protects from UV light
3. Langerhans cells - immune function
4. Merkel cells/discs - light touch sensory receptor
Name the 5 strata from top to bottom of the epidermis. Which layer contains stem cells?
- Corneum
- Granulosum
- Spinosum
- Lucidum - palms, fingertips and soles only for extra wear and tear
- Basale - stem cells divide and fill above for growth and repair
In which dermal layer are Meissner’s corpuscles found? What do they do?
Papillary layer of dermis - touch/pressure receptors
Name two pigment proteins responsible for skin color.
Melanin (main) and carotene (absorbed)
What are the three layers, from outside to in, of any hair?
Cuticle, cortex, medulla
Which part of the hair follicle contains blood vessels and receives nutrients at the base of the hair?
Papilla - blood vessels/capillaries at the base called hair bulb
How does Rogaine work in stimulating hair growth?
Vasodilation to improve blood flow through capillary bed of papilla.
Where do you find hair follicle free nerve endings?
Around the follicle - gives hair touch sensation
When your hair “stands on end” or you have “goosebumps” it is due to:
Arrector pili muscle
What is brown hair color due to? How about blonde or grey?
Brown/black - more melanin
Blonde - less melanin
Grey - lack of melanin
What are the functions of sebaceous glands?
Secrete oil called sebum
What is found in sebum?
Lipids - triglycerides, cholesterol
Contrast eccrine and apocrine sudoriferous glands. Which opens to the epidermis? Name three substances found in sweat.
Eccrine - open directly onto skin surface through pores exiting epidermis, make sweat through exocytosis mostly (water, salts, urea) for cooling
Apocrine - active at puberty, open into hair follicle, mix of organic compounds, pinch off part of cell so mix includes lipids, secretion can be behavioral (anxiety)
Which glands make ear wax? How is it protective?
Ceruminous glands - thick wax inhibits microbial growth and penetration (ear canal)
Following the steps of the negative feedback mechanism, what happens to the skin to cool the body in thermoregulation?
Thermoreceptors send signal to hypothalamus which directs effectors in skin. Sweat glands sweat to create evaporative cooling on skin surface. Blood vessels in dermis near surface vasodilate (increase diameter/flow) to release heat to air.
