Notesale: Turn your study into money

Document Preview

Extracts from the notes are below, to see the PDF you'll receive please use the links above

---

Nutrition
Food – consists of organic and inorganic compounds which supply energy to or are
incorporated into the composition of an organism
...

Diet – the foods that are consumed by an organism
...

4 most common elements in organic molecules

-carbon

-hydrogen

-oxygen

-nitrogen
Polar Molecule – a molecule with regions of partial negative and partial positive charge
H20 

oxygen – negative

hydrogen – positive
Cohesion - the force of attraction between molecules of the same substance (causes the
“stickiness” of water)
Important in living organisms because it prevents water from freezing or turning into gas as
energy is needed to overcome cohesion before water’s temperature is changed
Adhesion - The attraction between the molecules of one substance and the molecules of
another substance (causes water to “stick” to other objects)
Important in living organisms because water adheres to many substances making it one of the
best solvents
Element extremely useful in living systems- Carbon
...

Carbohydrates- compounds of carbon, hydrogen and oxygen typically in the ratio 1:2:1
...
Most commonly C6H12O6

Glucose

!
Fructose

!
Galactose

!

!

!
Disaccharides – The molecule formed by joining 2 simple sugars
...

3 common disaccharides

Sucrose = fructose + glucose



!
Lactose = galactose + glucose



!
Maltose = glucose + glucose

!
Polysaccharides - When several simple sugars are joined by dehydration synthesis
chitin –makes up the shell of insects

cellulose –makes up the structure in plants

starch –is used for short term energy storage in plants

glycogen –is used for short term animal energy storage
Polymers – Large molecules consisting of chains of repeating units
Dehydration Synthesis - When 2 simple molecules bond together to form a more complex
molecule by the removal of water
Hydrolysis - The process when disaccharides and polysaccharides may be broken apart by the
addition of water
...
18 kilojoules
1699 – the minimum requirement in order to sustain life of an average sized
human

2703 – amount required to maintain good health in temperate region such as
Canada

2297 – amount required to maintain good health in the tropics
Basal Metabolic Rate - the basic amount of energy an individual needs to maintain body
functions
Mass in kilograms X
...
2

Medium active day – BMR X 1
...
5
Lipid – the organic compound other than carbohydrates, consisting of carbon, hydrogen, and
oxygen
...
A carbon chain and one or more carboxyl
groups; one of the end products of the digestion of fats
Carboxyl Group (COOH) – The characteristic chemical group of organic acids
Signify an acid

!

!
Saturated Fats – Fats formed from fatty acids in which all carbon-to-carbon bonds are single
bonds

!
Unsaturated Fats - Fatty acid molecules that have one or more double or triple carbon-tocarbon bonds
Polyunsaturated Fats – a fat that has chains with more than one double or triple carbon-tocarbon bond
Glycerol

!
Fat –The molecule formed by the dehydration synthesis of three fatty acid molecules and one
glycerol molecule
...
It consists of one or more polypeptides bonded
together
...

1 gram of protein = 4 calories
Proteases –enzymes that break down proteins
Amino Acid - The structural units of proteins consisting of a carboxyl group, an amino group,
and a carbon chain
All human protein is made up of 20 different amino
acids

plants – 12

meat - 8

!
!
Peptide Bond - the bond formed between 2 amino
acids by dehydration synthesis
Dipeptide – the molecule formed when 2 amino acids are joined by a peptide bong
Polypeptide – a chain of amino acids joined by peptide bonds
Urine - the way the body removes wastes from the body by converting them to urea after
burning the amino from protein
Catalysts – a substance that increases the rate of a chemical reaction without being changed
itself, they are inorganic enzymes
The ability of enzymes to act as catalysts depends on their shape
...


!

!
Enzyme – Protein catalysts that are necessary for most of the chemical reactions that occur in
living cells
-enzymes are not used up in the reaction and they are not changed
...

Small amounts of an enzyme can cause the reaction of large quantities of substrate by
enabling cell reactions to take place at normal temperatures
-enzymes work best at 37°C

-each enzyme works best at a certain pH

-the rate of an enzyme-controlled reaction depends on the concentrations of the enzyme and
substrate as the rate is controlled by how often enzyme and substrate molecules bump into
each other
Coenzyme - substances some enzymes need to function
...

Each enzyme can catalyze a reaction only of those substances
Induced-fit model – The enzyme is not a rigid shape, the enzyme changes shape slightly as
the substrate enters the active site
Enzyme Specificity - when one enzyme only works on one molecule
Vitamins – coenzymes or are converted into coenzymes in cells
...

Anorexic Nervosa –an eating disorder controlled by the fear of gaining weight
...

Scurvy – results from the deficiency of vitamin C
...

Rickets – the softening in bone or impaired metabolism by the lack of vitamin D
...

Night Blindness –Caused by a vitamin A deficiency
Pellagra – a deficiency disease caused by the lack of niacin which causes diarrhoea,
dermatitis, dementia and sometimes death
...


!



---