Tissue Types and Integumentary System

Connective Tissue (45% of you) Function: Holds us together, gives us support, protection Types: – Bones – Blood – Cartilage – Adipose (fat) – Ligaments & tendons – Lower levels of skin

Epithelial Tissue (3% of you) Function: lines internal and external surfaces of the body Types – More than you need to know Examples: outer skin layer, digestive track lining, lung lining, etc.

Muscle tissue (50% of you) Function: contracts to move stuff Types: – Skeletal – Smooth (stomach) – Cardiac (heart)

Nervous Tissue (2 % of you) Function: send messages in the form of electrical impulses One type: neurons

On to the integument! Consists of: skin, hair and nails Fun facts: – Word “integument” is from Latin, means “covering” – Your skin weighs 8 pounds – Every minute 30,000-40,000 dead skin cells fall off you – Your skin has a totally new surface every 30 days

Functions of the Integumentary System 1. Bad stuff out: Protection from radiation, germs, pollution 2. Good stuff in: especially water 3. Regulate temperature: sweat and shiver, science word: thermoregulation 4. Sensation: pain, heat, pressure, texture 5. Messaging to other humans: blushing, odors 6. Vitamin D: formed when UV hits skin cells

Anatomy of the Integumentary system

Skin’s layers Epidermis: – 4-5 layers of epithelial tissue – Cells generated at the bottom, pushed up – No blood – Melanin – Keratin

Dermis – Connective tissue – Forms fingerprints – Sensory receptors – Blood vessels – Produces skin’s products Subcutaneous layer – Connective and adipose tissue – Insulates – Anchors skin

Hair, Nails, Sweat and oil Hair and nails: – Made of keratin – Hair grows from follicle Sweat – 2 kinds (eccrine, apocrine) – From seat glands Oil (sebum) – Protects skins and hair – From sebaceous glands

Skin diseases Eczema Skin cancer