Biological Molecules Flashcards
Are all molecules carbon based?
Biological molecules are carbon based except for some inorganic molecules
What roles do small molecules often play ?
As building blocks for macromolecules and as some other specific function in their own right
What is the Composition of a cell?
Water 70%
Inorganic ions 1%
Small organic molecules 3%
Macromolecules 26%
What is the general formula for sugars ?
(CH2O)n
What are some functions of carbohydrates?
Energy storage , fuel, metabolite and structural element
What are the two types of monosaccharides?
Ketone based or aldehyde based
What does it mean for a carbon atom to have a chiral centre?
The molecules can make mirror images of each other,can never superimpose so therefore are enantiomers
State the location of the ketone/aldehyde group in the D configuration of glucose
The aldehyde/ketone group will be most distant from the asymmetric c-atom
Condensation reaction
One molecule of H2O is released for every bond formed in a reaction
Why can we not break down cellulose?
Cellulose contains 1-4 beta glycosidic bonds which we cannot break down
How does glycogens structure help its function?
Glycogen is branched and therefore able to form 1-6 bonds aswell as 1-4 ,enabling more molecules of sugar to be packed together in one space.
What is an oligosaccharide ?give an example
Polysaccharide with different types of monosaccharides
Eg: blood group
What triggers the breakdown of glycogen and what does it break down into?
Tyrosine triggers the breakdown into adrenaline
How is histidine converted into histamine ?
Histidine is converted into histamine through the loss of CO2 in a vasodilator
What makes up a nucleotide ?
Sugar,phosphate and base
Why is sugar-phosphate binding important ?
Creates chains which are needed when DNA forms a double helix .
In a DNA helix,chains are going anti-parallel from 5’ end to the 3’ end
Why is Adenosine 3’,5’-cyclic monophosphate(cAMP) important?
It is essential for blood pressure regulation
What is Adenosine 5’ -monophosphate(AMP) involved in?
RNA synthesis
What produces more ATP ,fats or glucose?
Fats produce significantly more ATP than glucose on its own
Where do you find saturated fats(unhealthy) ?
Found predominantly in animal fats that we consume within our diets
Why are saturated fats considered healthy fats?
A reactive metabolite would react with the fatty acid , breaking the double bond . Providing an energy source from that , metabolite and can then be reabsorbed by the fatty acid instead of going elsewhere
Describe a triglyceride
One glycerol reacting with 3 fatty acids joined by an ester bond .releasing one molecule of water per bond
Describe a phospholipid
One glycerol , two fatty acid chains and one phosphate group and one head group
Give some functions of lipids
Phospholipid bilayer
Liposome
Micelle(fats transported throughout the body )
Bilayer sheet
What is cholesterol?what enables it to intercalated into the membrane?
A steroid
Different components of its structure
What parts of cholesterol do the phospholipids react with?
Oh group reacts with polar head and steroid scaffold reacts with fatty acids
Why is cholesterols role in the membrane so important ?
Cholesterol decreases fluidity and increases flexibility of the membrane .
It reduces permeability for soluble molecules and helps stabilise the membrane with transmembrane proteins which help increase rigidity
Diabetes (insulin dependant)
Absence of a protein hormone (insulin)leads to failure to regulate blood glucose
Sickle cell disease
One amino acid change (glutamic acid to a valine) in a gloving chain causes haemoglobin to aggregate into polymers -changes red blood cell nick cave disc to moon shape
Cystic fibrosis
Absence of a membrane protein that transports chloride leads to altered properties of secretions
