Test 4 Flashcards
4 elements that make up molecules of human body
- oxygen- 65%
- carbon- 18.5%
- hydrogen- 9.5%
- nitrogen- 3%
every atom atom has 3 parts
- electron (negative)
- proton (positive)
- neutron (neutral)
isotope
elements with different number of neutrons
Major group of molecules
carbohydrates
lipids
amino acids and proteins
nucleotides and nucleic acids
glucose
main source of energy
polysaccharides
long chain with 2 or more sugar units
monosaccharides
1 sugar unit
ex: fructose, glucose
disaccharides
2 sugar units
ex: lactose, sucrose
complex carbs
starch, cellulose, chitin
glycogen: stored in our liver
Types of lipids
fats
phospholipids
sterols
waxes
fats
comprised of glycerol molecule and long tail of fatty acids (hydrocarbon)
triglycerides
fats in most foods
solid at room temperature or liquid
saturated
single bonds
ex: stearic acid
unsaturated
double bonds
ex: linolenic acid
trans fat
formed when unsaturated fats are hydrogenated
unhealthy fat- increases risk of heart disease
phospholipids
molecule has 2 fatty acid tails
ex: main component of cell membranes
sterols
steroid hormones, cholesterol
waxes
birds use waxes to waterproof feathers
ex: bees make honeycombs
proteins and amino acids
main building blocks of life
skin, bone, muscles, cartilage, feathers
needed in diet
enzymes
break down foods
hemoglobin
help blood clot