Integumentary System Chapter 5

Lesson 1 Primary structures of the skin

Do Now Read Medical Focus: Body Art and answer questions

Structure Cutaneous membrane Adults: 20.83 sq feet Largest organ in the body 4 types of tissue: epithelial, connective, muscular, nervous Epidermis = outer Dermis = inner Hypodermis = between skin and structures

Epidermis Structure 3 layers Outer Thin Epithelial tissue No blood vessels Tightly packed cells Stratum corneum Stratum lucidum Stratum basale

Stratum Corneum Most superficial Waterproof Keratin (protein) Protects from water loss/gain Keratin (protein) Protects from invaders

Stratum Lucidum Protection from friction Found in thick skin Hands, feet elbows

Stratum Basale Deepest layer Produces new cells Uses sensory nerves Pain receptors send messages to the brain

Dermis Inferior to epidermis Dense connective tissue Thick layer Collagen and elastic fibers Flexible Blood vessels Dermal Papillae: fingerlike tissue which anchors the dermis to the epidermis

Hypodermis Below dermis Between dermis and body structures (bones, tendons, muscles) Loose connective tissue Fat Insulates body Excess = obesity

Content Check The deepest layer of the epidermis is the ____________________ Blood vessels can be found in: a) all 3 layers of skin b) the dermis only c) the hypodermis and dermis

In class assignment Read pg. 92 “I.C.E. – In Case of Emergency” What is a first responders role in treating burns? What is the “rule of nines” What does “ABC” Stand for? Describe the difference between 1st, 2nd, and 3rd degree burns. What are the major complications of burns?

Homework Text pg. 96 “Study Questions” # 1-4

Lesson 2 Analyzing fingerprints

Lesson 3 Accessory structures

Do Now Pluck a strand of hair from your own head. Describe the following: Color Texture Density Flexibility Strength

Hair Structure of hair Accessory structure Epithelial tissue Fine and downy except on head Found on all body parts except: palms, soles, lips, nipples, external reproductive organs Oil gland Sebaceous glands Smooth muscle Errector pilli allows hair to stand on end

Hair Follicles Located in the dermis Divide rapidly producing new hair cells As hair is pushed away less nutrients are received Root = within the follicle Shaft = beyond the skin

Nails Accessory structure Epithelial tissue Nail root: divides to push out new nail Cuticle: large amount of cell division Vascularized creates pink color of unpainted nails

Content Check Which part of the hair contains actively growing cells? a) base of hair follicle b) hair root c) hair shaft

In class assignment Forensic worksheet

Homework Text pg. 96 “Study Questions” #5

Lesson 4 Hair

In class assignment Analyze hair samples

Lesson 5 Glands and Homeostasis

Do Now Read pg. 93 Medical Focus “Body Art: Buyer Beware” What are the risks of tattoos and piercings? Why do people take that risk? How permanent is body decoration?

Glands Functions Types Specialized groups of cells that produce and secrete substances into ducts Sweat glands Sebaceous glands Mammary glands

Sweat Glands Present in all regions of the skin Most glands are found in the palms and soles Why? Become active when under stress What is stress? What causes stress? Use exocytosis to release sweat What is exocytosis?

Apocrine Glands Type of sweat gland Open onto hair follicles Found in armpits, groin, anus Become active at puberty Act as an attractant to the opposite sex

Eccrine Glands Type of sweat gland Open to the surface of the skin Become active when hot Lower body temperature EXCRETE salts, urea, water What is excretion?

Sebaceous Glands Associated with hair follicles Lubricates skin and hair Makes skin waterproof Kills bacteria Secrete oils called sebum If you don’t release sebum the glands become inflammed and cause acne How can this be prevented or treated?

Mammary Glands Similar to apocrine glands Found in the female breast Produce milk at childbirth Can continue to produce milk as long as a child is nursing

Aging Cell division (mitosis) decreases Demis becomes thinner Adipose in hypodermis decreases What effect might this have on the elderly? Fewer blood vessels Hair follicles decrease Melanocytes decrease Grey hair Pale skin UV radiation causes wrinkles , benign skin growths and skin cancer

The Integument and homeostasis Protection Regulate water loss Excretion Vitamin D Sensory organ Body temperature regulation

Content Check Which glands begin secretion at puberty and contain a sex attractant? _________________ Which of the following pathologies causes women to develop excessive body and facial hair? a) alopecia b) hirsutism c) acne vulgaris

Homework Text pg. 96 “Study Questions” # 6 - 11

Lesson 6 Skin Cancer

Do Now What causes skin cancer? Can anyone get skin cancer?

In class assignment Watch a video on skin cancer and answer the worksheet

Lesson 7 Review

Do Now Text pg. 96 “Learning Objectives” # 1-5

Homework Text pg. 96 “Learning Objectives” # 6 - 11