biological molecules: types of proteins

Question 1

3 different types of proteins

Answer 1

globular
conjugated
fiborous

Question 2

globular proteins

Answer 2

compact,water soluble and roughly spherical

Question 3

how are globular proteins formed

Answer 3

when proteins fold into their tertiary structures in a way the hydrophobic r-groups are kept away from the aqueous environment
the hydrophilic r groups are kept on the outside of the r groups
making it soluble

Question 4

example of a globular protein

Answer 4

insulin

Question 5

insulin

Answer 5

hormone involved in the regulation of blood glucose concentration
hormones are transported to bloodstream so they need to be soluble

Question 6

what are conjugated proteins

Answer 6

globular proteins that contain a non protein component called a prosthetic group

Question 7

different types of prosthetic groups

Answer 7

lipins, carbohydrates - lipoproteins or glycoproteins
haem groups - iron in the middle
catalase and haemoglobin both contain haem groups

Question 8

what is the haemoglobin

Answer 8

red, oxygen carrying pigment found in our red blood cells
it is a quaternary proteins made from 4 polypeptide chains
2 alpha and 2 beta subunits which each contain a prosthetic haem group

Question 9

structure haemoglobin

Answer 9

quaternary protein with 4 polypeptide chains
2 alpha 2 beta subunits which each contain a prosthetic haem groups

Question 10

what enables the haemoglobin to transport oxygen

Answer 10

the iron 2 ions present in the haem groups which can combine reversibly to an oxygen molecule
can pick up oxygen in lungs transport it to whatever cell it needs then release

Question 11

catalase

Answer 11

an enzyme
quaternary proteins containg 4 haem groups
iron 2 ions allow catalase to interact with hydrogen peroxide and speed up its breakdown
because its a common byproduct in metabolism but can be damaging to cells if allowd to accumulate so catalase makes sure it doesnt happen

Question 12

what are fibrous proteins and examples

Answer 12

long insoluble strong molecules due to organised structure
examples are keratin, elastin and collagen

Question 13

keratin

Answer 13

group of fibrous proteins present in hair, nails and skin
has many cysteine which means many stron disulphide bonds forming strong, inflexible and insoluble materials
amt of disulphide bonds determines the flexibility

Question 14

elastin

Answer 14

fibrous protein found in elastic fibres
they are present in the walls of blood vessels and in the alveoli of lungs
flexible when needed and can return to original size

Question 15

collagen

Answer 15

fibrous protein
a connective tissue found in skin, tendons, ligaments and the nervous system
3 polypeptides wound in a long rope like structure
flexible