Human Body Systems Review

Muscular System

• Function: to support and provide mobility• Main Parts:– Smooth muscle: controlled by the autonomic

nervous system– Cardiac muscle: found in the heart, acts like

rhythmic smooth muscle,– Skeletal muscle: move us around and is

responsible for most of our behavior. It is attached to bones.

Muscular System

• Tendons:• A tough band of tissue that connects muscles to tissue

• Voluntary Muscles:– Muscles that are controlled by the brain– Skeletal and Smooth Muscles

• Involuntary Muscles:– Muscles that are connected to uncontrollable

nerves.– Cardiac muscles

Muscular System

• Illnesses:– Muscular dystophy

• Fun Facts:– There are over 700 different skeletal muscles– It takes 17 muscles to smile and 43 to frown– The strongest muscle in the body is the tongue– We are about 1 cm taller in the morning than in

the evening – It takes 200 muscles to make one step

Skeletal System

Function: support, movement, protection, and the production of blood cells.

Skeletal System

• Compact Bone:– Dense, rigid, and shaped like a cylinder– It protects the spongy bone

• Spongy Bone:– Light, porous, and looks like a honeycomb

Skeletal System

• Axial Bones:– Bones of your head and trunk

• Appendicular bones:– Appendicular is the adjective for appendage– Bones of your arms and legs

Skeletal System

• Protection:– Skull- Brain– Ribs- heart and lungs – Backbone- spinal cord

• Illnesses:– Osteoporosis

• Fun Facts:– Hardest bone is your jaw bone– Babies are born with 300 bones, but by adulthood

the number is reduced to 206 bones

Nervous System

• Function: its like the body’s wiring and allows us to perceive, comprehend, and respond t o our environment.

• Nerves:– Connect to each other and allow us to send signals

back and forth between parts of our body

Nervous System

• Autonomic Nervous System:– Controls involuntary actions. • Ex. Beating of your heart, swallowing

• Voluntary Nervous System:– Controls your body movements

• Central Nervous System:– Head and trunk

• Peripheral Nervous System:– Arms and legs

Nervous System

• Illnesses– Nerve disorders – Stroke– Alzeheimer’s disease

• Fun Facts– There are more nerve cells in the human brain

then there are stars in the sky– If we were to line up all the neurons in our body it

would be around 600 miles long

Respiratory System

• Function: a series of organs that takes in oxygen and expels carbon dioxide

• Main Organs– Nasal cavity or mouth: the

starting and ending point for breathing

– Trachea: allows air to travel to the lungs

– Lungs: allows gas exchange

Respiratory System

• Gas that we inhale: Oxygen• Gas that we exhale: Carbon Dioxide• Illnesses:– Lung cancer– Cystic Fibrosis

• Fun Facts:– People younger then 30 breathe double the

amount of people older than 80– Yawning brings more oxygen to the lungs

Circulatory System

• Function: transports blood and oxygen from the lungs to other parts of the body

• Main Organs– Heart: pumps blood through the body– Arteries, veins, and capillaries: carry blood

through out the body

Circulatory System

• What is blood pressure?– The pressure of blood on the walls of blood

vessels• What does it mean if your blood pressure is to

high? Low?– High (Hypertension): causes strain on your blood

vessels and results in in damage– Low (Hypotension): causes dizziness and fainting

Circulatory System

• Illnesses: – Heart attack – Heart diseases

• Fun Facts:– Lay out all the blood vessels end to end, it would

stretch out 60,000 miles

Digestive System • Function: the organs work together to absorb

nutrients from food• Major Organs:– Mouth– Throat– Esophagus– Stomach– Small Intestine– Large Intestine

Digestive System

• Mechanical Digestion: Breaks down food into smaller pieces by chewing

• Chemical Digestion: Breaks down food into smaller pieces by chemicals in your stomach

• Illnesses:– Chron’s Disease

• Fun Facts: – Esophagus ranges from 10 to 14 inches in length– We make 1 to 3 pints of saliva a day

Endocrine System

• Functions: collection of glands that secretes hormones

• Major Organs– Thyroid– Adrenal gland– Pancreas– Ovaries (women)– Testes (men)

Endocrine

• Hormones: a chemical that regulates our body• Homeostasis: our body being at equilibrium ie. We

do not have a temperature• Illness:– Metabolism disorders – Diabetes – Alcohol poising

• Fun Facts:– Diabetes was once tested by tasting urine– Stress kicks the endocrine system into high gear

Excretory System

• Function: the process of removing waste from the body

• Major Organs:– Kidney: produce important hormones, filter blood,

produce urine – Ureter: transport urine from the kidney to the

bladder– Urethra: carries the urine from the bladder to the exit

– Bladder: stores urine before it is excrete

Excretory System• What is excretion?’– Only the removal of metabolic waste

• What is elimination?– The removal of indigestible material and metabolic

waste • Illnesses:– Bladder infection– Kidney stones

• Fun Facts:– A person pees about 3000 times a year– The bladder can hold 16-24 ounces of urine - A person poops about 305 pounds a year