Unit 3: Human Body

K W L

• Body Organization • Cell Tissue Organ Organ System

Homeostasis: all things in the body are in balance

• Skeletal System– Skeleton = “a dried body”

• 206 bones• Provides shape and support• Allows you to move• Protects your organs• Produce blood cells• Stores minerals and other

materials until you need them• Vocabulary

– Vertebrae = backbone– Joint = place where 2 bones

meet… held together by strong connective tissue called ligaments

– Cartilage = covers ends of bone to keep them from rubbing together

• Bones = complex living structures that grow and develop– A) Structure:

• Outer = compact bone: hard and dense but not solid. Small canals carry blood vessels and nerves from the bone’s surface to the living cells within the bone!

• Inner and ends of bone = spongy bone: has many small spaces within it. Lightweight but strong

• Inside spaces of spongy bone = marrow: soft connective tissue. Red (produces red blood cells) and Yellow (stores fat for energy).

• Diseases: – A. Osteoporosis: bones lose

calcium as they get old makes them weak and break easily. More common in women than in men! Regular exercise and a diet with lost of calcium will help prevent this.

– B. Arthritis: “inflammation of the joints” disease of the joints that makes movement painful.

• Injuries: – A. Fracture = break in

the bone. • Simple: cracked or broken in

2 or more pieces• Compound: broken ends of

bone stick through skin

– B. Dislocation = end of bone comes out of the joint

– C. Sprain = ligaments are stretched too far and tear in places.

• Muscular System • Allows movement of the body and internal organs

• 1. Types of muscles– A) involuntary: you don’t

know you’re doing it. Ex: breathing or digesting food

– B) voluntary: you choose to do it. Ex: smiling or walking

• 2. Types of muscle tissue– A) skeletal:

• attached to the bones of your skeleton and provide force that moves your bones.

• AKA striated• voluntary muscles• React quickly but also tire quickly

– B) smooth: • involuntary• Found inside many internal organs

like the stomach• React slowly and tire slowly

– C) cardiac: • Found only in the heart• Involuntary but also striated• Does not get tired

• Integumentary System

• Skin, hair and nails• Protects the body from

injury, infection, and water loss

• Helps regulate body temp. eliminate wastes, gather info about the environment and produce vitamin D

• 1. Layers of skin: – A. epidermis: outer layer.

• No nerves or blood vessels.• Every time you rub your hands

together, you lose thousands of dead skin cells!

• Melanin = pigment (colored substance) that gives skin its color.

– B. Dermis: inner layer• Contains nerves and blood

vessels • Also contains sweat glands, hairs,

and oil glands

• 2. Disease = cancer– Cells divide uncontrollably– Too much sun exposure can

lead to skin cancer

• Digestive System • Food: provides your body with materials for growing and for repairing tissues. Provides energy

• Nutrients: substances in food that provide raw materials and energy needed to carry out processes– Carbohydrates– Fats– Proteins– Vitamins – Minerals – Water

• Calorie: amount of energy in food– Recommended = 2,000

Calories per day– Food pyramid = guide to

how much of what to eat– Food Label = on package of

food and gives info about how much fat, calories, etc are in a serving

• Carbohydrates: main source of energy– A) simple = sugars like

glucose– B) complex = starch

• Better than simple

Recommended amount = 45-65% of calories a day come from here

• Fats: Contain 2 x’s as much energy as carbohydrates– 1 g fat = 9 C of energy!– Needed for energy, form part of cell

membrane, protect internal organs and insulates your body

– Kinds:• A) unsaturated = liquid at room temp.

(oils)• B) saturated = solid at room temp (crisco)• C) trans = manufacuturer adds hydrogens

to vegetable oil to make it stay fresh longer but is VERY unhealthy!

• Cholesterol: your liver can make all the cholesterol your body needs…not a necessary part of your diet

• *Recommended = no more than 30% of C come from fats per day

• Proteins: needed for tissue growth and repair– Recommended 10-35% of C

from here– Made up of amino acids…must

have these to do all the things your body does

– Your body creates ½ you need…the other ½ comes from your diet.

• Vitamins and minerals:– Vitamins: helpers in

chemical reactions in your body

• ex: vitamin D helps body absorb calcium

– Minerals: (nutrients not made by living things)

• From sol and absorbed into plants’ roots.

• Ex: Calcium and iron

• Water: Can survive Weeks without food but only days without water!– Your body is 70% water– Recommended = 2 L per day!

• Digestive Process: – break down food to

molecules (very small pieces) molecules absorbed into blood and carried throughout body wastes eliminated from body

• Diegestive Parts:– Mouth = digestion begins here!– Esophagus = connects mouth and

stomach– Stomach = turns food into a thick liquid– Small intestine breaks liquid down and

absorbs nutrients– Large intestine = any water is

absorbed into the bloodstream and remaining material is eliminated

• Other Digestive Parts:• Liver = creates bile that breaks down fats• Gall blader = holds bile and passes it to

small intestine• Pancreas = produces enzymes that go into

the small intestine and help break down starches, proteins, and fats