Biology3 nutrition exam2

any substance an animal needs but cannot synthesize or produce in its own body

the process by which an animal mechanically and chemically breaks down its food to produce simple molecules that can be absorbed into the circulatory system

• lipids
• carbohydrates
• proteins
• minerals
• vitamins
• water

the amount of energy needed to raise the temperature of one gram of water by one degree Celsius

• fats; used primarily as a source of energy
• phospholipids
• cholesterol; used to make cell membranes and several hormones

• source of quick energy
• include simple sugars and polysaccharides
• animals store sugars as glycogen, a large branched chain of glucose molecules

• provide amino acids for building new proteins
• dietary protein comes from meat, milk, eggs, corn and beans
• our bodies can synthesize certain amino acids but the eight essential amino acids must be supplied by our diet

• elements that are required by the body
• needed for strong bones and teeth, muscle contraction, nerve functions, proper blood cell functions
• also act as parts of enzymes in certain body reactions

• play many roles in metabolism
• organic compounds that animals require in very small amounts
• the body cannot synthesize them
• water soluble or fat soluble

• dissolve in water or blood plasma and are excreted by the kidney; therefore do not build up in the body
• C and B complex

• can accumulate in the body and be toxic if present in too high a concentration
• K, A, D, E

• human body about 2/3 water
• principal component of saliva, blood, lymph, extracellular fluid, and cytoplasm within each cell

• ingestion: food through mouth
• mechanical breakdown: food into small pieces
• chemical breakdown: enzymes convert large molecules into small ones
• absorption: transfer of small molecules across the gut to the blood and then to the cells
• elimination: indigestible materials are expelled

• individual cells: in sponges; microscopic organisms are ingested by phagocytosis
• sac like: in jellyfish; both food and waste pass through a single opening
• tube: most animals

connects the mouth to the rest of the digestive sytem

conducts food to the somach

• stores and breaks down food, mechanically and chemically
• protein digestion begins (denatured) - pepsine (chemical for protein breakdown)

liver stores glycogen and detoxifies many poisonous substances