Food Flashcards
why is food necessary?
source of energy
makes chemicals for chemical reactions
growth and repair
what is food made up of?
6 common elements
5 dissolved salts
3 trace elements
what are the 6 common elements that make up food
carbon
hydrogen
oxygen
nitrogen
(More common)
phosphorus
sulfur
(Only sometimes)
what are the 5 dissolved salts that make up food
sodium
magnesium
calcium
chlorine
potassium
what are the 3 trace elements that make up food
copper
zinc
iron
what is a trace element
elements required in tiny amounts by the body
what are the essential food groups
protein
fats
carbohydrates
(Biomolecules)
vitamins
minerals
water
biomolecule
an organic substance made by living organisms to be used in chemical reaction
structural role of biomolecules
how the biomolecule contributes to the build-up/ structure of a cell or organism
metabolic role of biomolecules
the sum of all chemical reactions in the body
basic unit of protein
amino acids
chemical composition of protein
ALWAYS:
carbon
hydrogen
oxygen
nitrogen
SOMETIMES:
sulfur
phosphorus
structure of protein
amino acids join together to form a chain called a protein
amino acid>polypeptide chain>protein
how many types of amino acids is there in a protein?
20
what determines the type of protein it is
the number and sequence of amino acids in a chain determines a protein. the way the chains fold gives the protein its qualities
what are the 2 types of protein
fibrous (structural)
globular (metabolic)
what is an example of fibrous protein
keratin in hair + nails
what is an example of a globular protein
enzymes i.e., amylase
functions of protein
structural: insulation + protection
metabolic: hormones control body responses
peptide
a chain of less than 20 amino acids
polypeptide
many peptides in a chain
what are the 2 types of lipid
fats + oils
give 1 difference between fats and oils
fats= solid at room temperature
oils= liquid at room temperature
basic unit of lipids
triglyceride
chemical composition of lipids
carbon, hydrogen, oxygen
structure of lipids
triglycerides are made up of 1 glycerol and 3 fatty acids
phospholipid
one fatty acid is replaced with a phosphate group
types of lipids
phospholipids
lipids
function of lipids
structural: insulation (cell membrane)
metabolic: broken down in respiration for energy
basic unit of carbohydrates
monosaccharide
chemical composition of carbohydrates
carbon
hydrogen
oxygen
structure of carbohydrates
monosaccharides join together forming a carbohydrate
what are the 3 types of carbohydrate
monosaccharides
disaccharides
polysaccharides
monosaacharides
single sugar unit
glucose, fructose, galactose
disaccharide
2 monosaccharides joined together
maltose, sucrose, lactose
polysaccharides
many sugar units joined together
function of carbohydrates
structural: cellulose forming cell wall
metabolic: glucose made in photosynthesis
what are the water-soluble vitamins
B, C,
fat soluable vitamins
A, D, E, K
function of vitamin c
healthy gums and skin
aids iron absorption
sources of vitamin c
fresh fruit and veg
deficiency in fruit and veg
scurvy - bleeding gums
functions of vitamin D
healthy teeth and bones
calcium absorption
sources of vit D
oily fish, dairy food
deficiency of Vit D
rickets
tooth decay, osteomalacia
what are the 2 plant minerals
magnesium
calcium
what are the 2 animal minerals
iron
calcium
function of magnesium
assists chlorophyll formation
source of magnesium
salt in soil
function of calcium (plants)
helps cell walls attach to each other
source of calcium (plants)
salts in soil
function of iron
forms haemoglobin
source of iron
red meat, dark green veg
function of calcium (animals)
healthy bones and teeth
sources of calcium (animals)
milk, cheese
how much water are humans made up of
70-95%
why is water important?
component of cells- cytoplasm
excellent solvent
medium for chemical reactions
movement through membranes
good absorber of heat
name a catabolic process that produces monosaccharides
respiration
what is the general formula of carbohydrates
Cx(H2O)y
what is the formula of glucose
C6H12O6
why is the most common value of x/y in the general formula of carbs
6
what is the ratio of H to O atoms in a carbohydrate
2:1
name the main structural polysaccharide in plants
cellulose
what carbohydrate is always found in DNA
deoxyribose
what carbohydrate is found in RNA
ribose
where precisely in the plant cell would you find cellulose
cell wall
name a storage polysaccharide in animals
glycogen
state the use of benedicts solution / fehlings test
to test for reducing sugar ie glucose
give the 2 biomolecular components of lipids
glycerol and fatty acids
where would you find phospholipids in human cells
cell membrane
give a structural role of lipids in cells
make up the cell membrane
describe the structure of a triglyceride
glycerol and 3 fatty acids
describe a phospholipid structure
a triglyceride where one fatty acid has been replaced by a phosphate group
identify 1 difference between a phospholipid and triglyceride
a triglyceride has 3 fatty acids and a phospholipid has 2
give a metabolic role of lipids in cells
energy source for respiration
what do carbohydrates and fats have in common
have the same elements C,H,O
how may one fat differ from another in terms of chemical composition
different fatty acids
how do proteins differ from lipids/carbs
they contain nitrogen
what are the final products in the digestion of a protein
amino acids
differenciate between a peptide and a polypeptide
a peptide is a chain of less than 20 amino acids
a polypeptide is many peptides joined together
give a metabolic role of proteins in the human body
hormones control reactions in the body
how many amino acids make up a protein
200+
name the chemicals used to test for protein
sodium hydroxide
copper sulphate
what colour indicates the presence of protein
purple
state a use of biuret reagent in the lab
to test for protein
