Biological molecules Flashcards
core concepts (70 cards)
what is the importance of magnesium?
it is an important constituent of chlorophyll and essential to photosynthesis, plants lacking magnesium can not make chlorophyll so the leaves turn yellow (chlorosis) growth is stunted from lack of glucose. mammals need magnesium for their bones
what is the importance of iron?
iron is part of haemoglobin and a lack of it can lead to anaemia in humans
what are phosphate ions used for?
making nucleotides and are a constituent of phospholipids found in biological membranes
what is calcium used for?
important structural component of plant cell walls & bones
what are inorganic ions?
an ion that has no more than one carbon atom
how much micro/macronutrients do humans need?
micronutrients= needed in minute traces
macronutrients= needed in small concentrations
describe polypeptide primary structure
primary structure is determined by the base sequence on one strand of the DNA, it is a sequence of amino acids joined together by peptide bonds to create a polypeptide chain
describe and draw a dipeptide
- NH^2,CHR^1,CO-NH,CHR^1,COOH
- the resulting compound of a condensation reaction
between two amino acids bonded together by a peptide
bond
what is hydrophobic interaction?
non-polar amino acids cluster together on the inside of a protein because they are repelled by water
explain polypeptide quaternary structure
consists of more than one polypeptide chain (tertiary structure) joined together mostly by disulphide and hydrophobic bonds, sometimes containing a prosthetic group e.g: haemoglobin
what is this?:
H
|
H - C - OH
|
H -C - OH
|
H - C - OH
|
H
A GLYCEROL
what is this?:
CH^2OH
|
C = O
|
HC - OH
|
HC - OH
|
CH^2OH
pentose sugar
a monosaccharide containing 5 carbon atoms
what is collagen
made from three identical left handed helix polypeptide chains wound around each other to form a triple helix.
held together by h-bonds. its insoluble in water. collagen molecules cross link through covalent bonds to form fibres which give strength
it is the most basic amino acid it fibrous and is found in the skin.
in each polypeptide chain every third amino acid is glycine.
describe haemoglobin
globular protein which has a metabolic function
it is a quaternary structure consisting of 4 globin molecules held together by h-bonds
has a prosthetic group made up of Fe atoms called the haem group which carry oxygen
what is this?:
H H O
| | ||
H - N - C - C - OH
|
R
amino acid
Amino group, R-group, variable group
what bond links phospholipids and triglycerides?
Ester bond
an oxygen atom joining two atoms one of which is a carbon atom attached by a double bond to another oxygen atom
O2 atom joins 2 atoms 1 of which is a C-atom attached by a = bond to O2
what is this?:
CHO
|
OH - CH
|
OH - CH
|
HC - OH
|
HC - OH
|
CH^2OH
hexose
what is a peptide bond
the chemical bond formed by a condensation reaction between the amino group of one amino acid & the carboxyl group of another
what is represented here?:
CH^2
|
S
|
S
|
CH^2
<
disulphide bond
a covalent bond between the sulphur atoms of two cysteine residues in a
what is this?:
O H
|| |
HO = O = C - …
|
H
head of a fatty acid
What is the difference between a saturated fatty acid and a non-saturated fatty acid?
a saturated fatty acids has only carbon- carbon single bonds where as an unsaturated fatty acid has one or more c=c double bond, which puts a kink in the chain
what is ?:
H O
| ||
H - C - O - C - R (1)
| O
| ||
H - C - O - C - R (2)
| O
| ||
H - C - O - C - R (3)
|
H
Triglyceride
1 glycerol & 3 fatty acid tails by a condensation reaction
draw a condensation reaction between a glycerol and three fatty acids
look up answer :)
what is an ionic bond?
a type of bond that occurs between oppositly charged ions
contribute to the folding of protiens into their tertiary structure
