Body Membranes & Skin: Integumentary System Chapter 4

Body Membranes Function of body membranes – Cover body surfaces – Line body cavities – Form protective sheets around organs

2 types of membranes Epithelial membranes – Cutaneous membranes – Mucous membranes – Serous membranes Connective tissue membranes – Synovial membranes

Epithelial Membrane: Cutaneous membrane Skin – Epidermis- stratified squamous – Dermis- dense connective tissue

Epithelial Membrane: Mucous membrane Lines all body cavities that are open to the outside of the body

Epithelial Membrane: Serous membrane Lines body cavities that are closed to outside of body – Peritoneum- abdominal cavity, evolved from coelom – Pleura- around the lungs – Pericardium- around the heart

Saggital section: peritoneum in green

Connective tissue membrane: Synovial membrane Lines cavity between joints

Integumentary System Skin (cutaneous membrane) Skin Derivatives – Sweat glands – Oil glands – Hair – Nails

Skin Functions: – protection of deeper tissues from chemicals, bacteria, and drying. – Regulates body temp – makes vitamin D. – Contains sensory receptors.

Skin Epidermis – stratified squamous epithelial tissue, no blood supply Dermis – dense connective tissue – blood vessels, nerves, skin appendages, produce fingerprints

Skin Color Pigment= melanin Amount of melanin depends on genetics & exposure to sunlight

Is a zebra black with white stripes or white with black stripes?

Sebaceous Glands Produce oil – Keeps skin from drying out – Kills bacteria Acne is an infection of the sebaceous gland

Sweat Glands Produce sweat that dumps into pores or hair follicles Sweat= water, salt, fatty acids, urea Acidic to kill bacteria Bacteria is what causes sweat odor

Fun (Smelly) Fact The bacteria in your armpits are more closely related to the bacteria in your friend’s armpits than the bacteria in your own pubic area.

Fun Fact On a hot day you can lose up to 7 liters of water X 7