food Flashcards
why do we need food
source of energy, growth and repair, provides chemicals for metabolic reactions
name the 4 biomolecules
carbohydrates, fats, proteins, vitamins
what is the hydrogen to oxygen ratio in a standard carbohydrate
2:1
define mono, di and polysaccharides and give an example of each
one (glucose), two (sucrose) and many (starch) sugar unites joined together
structural + metabolic role of carbohydrates
cellulose is used to form plant cell walls…. glucose is broken down in respiration to release energy
test for starch + glucose/reducing sugar
iodine- brown to blue
benedicts solution - blue to brick red
name the elements present in lipids
carbon, hydrogen, oxygen
what’s the difference between fats and oils
fats are solid at room temp, oils are liquid at room temp
describe the structure of the smallest lipid
tryglyceride- glycerol + three fatty acids
what is a structural role of lipids
phospholipids are component of cell membranes… tryglycerides form adipose tissue which protect internal oragns
metabolic role of lipids
tryglycerides can be stored as a source of energy
what is the test for lipids
brown paper test- lipids will create a translucent spoton brown paper
name the elements present in proteins
carbon, hydrogen, oxygen, nitrogen
what is the smalled form of a protein
amino acid
how many different types of amino acidsare there
20
what bonds different amino acids together
peptide bonds
name the two shapes of proteins
fibrous, globular
structural role of protein
skin, hair, nails (keratin)
metabolic role of protein
enzymes, antibodies and some hormones
test for protein
biuret solution turns from blue to purple/violet… no heat required
what chemicals make up biuret solution
sodium hydroxide and copper sulphate
name the two types of vitamins and give an example of each
water soluble (B,C) or fat soluble (A,D,E,K)
name a disease related to water or fat soluble vitamin defficiencies
water (C)- scurvy… fat(D)- rickets in children
what is the purpose of a named fat and water soluble vitamin
Vit C- forms connective tissues… Vit D needed to absorb calcium
name 2 minerals needed by plants
magnesium - forms cholophyll molecule… calcium- helps cell walls attach to each other
name 2 minerals needed by animals
calcium- needed fro strong bones and teeth… iron- helps carry oxygen in red blood cells
define metabolism
the sum of all chemical reactions in the body
name the two types of metabolic reactions
anabolic, catabolic
why is water needed in the body
good solvent, participates in chemical reactions, carries substances around the body (transport), good absorber of heat enery
