Integumentary System

what is the epidermis

outer layer of skin

what 4 cells are found in the epidermis

1. keratinocytes

2. maleanocytes

3. markel cells

4. langerhans cells

what are keratinocytes (2)

1. makes keratin that gives skin strength

2. creates waterprrof layer of skin

what is melanocytes

pigment

what is markel cells

thought to be touch sensation

what are langerhans cells

defends from invading cells on the skin

what are the 4 layers of the epidermis

1. stratum corneum (pointy layer)

2. stratum lucidum (clear layer)

3. granular layer

4. stratum spinosum/spiny layer

what is the dermis

structural strength

what are the 2 layers of the dermis

1. papillary layer

2. reticular layer

what is the papillary layer (2)

1. made of loose connective tissue, fibres, and ground substance

2. nerve endings/meissners copuscles

what is the reticular layer in the dermis

made of irregular connective tissue

what is the hypodermis/subcutaneous layer? (3)

1. used as a thermoinsulator

2. mechanical shock absorber

3. mostly made of adipose

fill in the blanks

top - epidermis

mid - dermis

bot - hypodermis

— — is where the fur is

thick skin or thin skin

what do melanocytes do when they are stimulated by UV light

deposit melanin to protect from the uv rays

define macrophage

immune cell

what movement type does langerhans cells have

diapedesis

define diapedesis

white blood cells squeeze through the walls of tiny blood vessels

what is the 6 functions of the epidermis

1. protection - chemical, physical, biological barrier

2. Body temp regulation - sweating and dermo flow

3. Cutaneous sensation - touch, pressue, pain, temp receptors

4. Metabolic function - synthesis of vitamin d precursor

5. Blood resevoir - dermal vascular supply

6. Excretion - eliminates nitrogenous wastes and salt in sweat

what is feeding the epidermis

dermis