Senses

Senses Vision Hearing Retina has specialized cells for sight Rods detect light Cones detect color Lens focuses images on retina Iris controls amount of light entering the eye Hearing Ear collects sound waves that stimulate hair cells (NOT hair) in the ear. Hair cells stimulate nerves, brain interprets sounds.

Senses (cont.) Smell and Taste Touch Both have cells that detect chemicals. Smell detects odors Taste detects flavor Smell heavily influences taste Touch Skin has cells that detect pressure, temperature, and pain

Digestive System

Parts of the Digestive System Mouth Esophagus Stomach Small and large intestine Liver & Gallbladder Pancreas

Functions of the Digestive System Breaks down and absorbs nutrients, salts, and water. Eliminates solid waste (feces)

Cool Digestive System Facts The average liver weighs about 3 pounds. The large intestine is home to about 100 trillion bacteria. The iron in a human could make a small nail. There is enough phosphorus in the human body to make 2,000 match tips.

Urinary System Structures: Kidneys, ureters, bladder Function: eliminates non-solid waste through urine. Waste includes water, salt, urea, minerals, and vitamins

Skeletal System

Structure of the Skeletal System Includes Bones Cartilage (found between bones, cushions) Ligaments (connects bones)

Functions Movement Supports and protects vital organs Blood Cell Production Stores Minerals

Muscular System

Organs of the Muscular System Cardiac, skeletal, and smooth muscle Tendons (attach muscle to bone)

Functions of Muscle Movement (circulate blood, move food through digestive system, move bones at joints) Produce body heat Maintain posture Stabilize joints

Super Interesting Muscle Facts You have more than 600 skeletal muscles. 40 muscles are used to frown, 20 to smile. The gluteus maximus is the largest muscle.