Biological molecules Flashcards
Why is water important?
Water is reactant important in reactions such as hydrolysis and is a solvent most reactions take place in a solvent so water is important
Water
Transports substances as its liquid and solvent and has a high specific heat capacity making it good for temp control.
Water structure
One atom of oxygen joined to two atoms of hydrogen by shared electrons- water is polar it has a partial negative charge on one side and positive on the other attraction between water called hydrogen bonding
What does hydrogen bonding give water?
Gives water a high specific heat capacity as they can absorb a lot of energy so is good in habitats aswell as a high latent heat of evaporation means water is great for cooling things
What are carbohydrates made off?
They are made from monosaccharides which are the monomers that make up the carbohydrates all have carbon hydrogen and oxygen
Monosacharide bonding
Glycosidic bonds, hydrogen atom on one monosaccharide bonds to the hydroxyl group on the other releasing a molecule of water; condensation reaction reverse is hydrolysis
Starch
Main energy source in plants
Amylose- Long, unbranched chain of alpha glucose coiled structure compact good for storage
Amylopectin- Long, branched chain side branches allow enzymes to get at the glycosidic bonds quickly so glucose can be released quickly
What is glycogen?
The main energy storage material in animals polysaccharide of alpha glucose has many more side branches means that stored glucose can be released quickly and compact
Cellulose
Long unbranched chain of beta glucose cellulose chains linked together by hydrogen bonds to form microfibrils.
Lipids: Triglycerides
They are macromolecules large molecular mass contain carbon, hydrogen and oxygen one molecule of glycerol with three fatty acids attached tails are hydrophobic. Contain ester bonds which is fromed by the condensation reaction and is called estrefication.
Saturated Fatty acids
They dont have any double bonds between their carbon atoms. The acid is saturated with hydrogen. Formula = CnH(2n+1)
Unsaturated Fatty acids
They have at least one double bond between the carbon atoms causing them to kink
Phospholipids
They are found in the cell membranes of all eukaryotes and prokaryotes and make up the phospholipid bilayer controls what leaves and enter the cells. Centre of bilayer is hydrophobic so water soluble substances cannot easily pass through it so acts as a barrier
Cholesterol
Hydrocarbon ring strucutre attached to a hydrocarbon tail has a polar hydroxyl group in animals is strengthens the cell membrane small and flattened allows it to fit between the bilayer bind to the hydrophobic tails making them pack more closely together less fluid.
What are proteins made off?
They are made of long chains of amino acids and are polymers and amino acids are the monomers of a protein dipeptide is formed when two amino acids join and more than two a polypeptide and a protein is made of one or more polypeptides
Primary structure
This is the sequence of amino acids in the polypeptide chain. Different proteins have different sequences of amino acids in their primary structure. A change in just one amino acid may change the structure of the whole protein.
Secondary structure
Polypeptide chain doesn’t remain flat and straight. Hydrogen bonds form between nearby amino acids in the chain. This makes it either coil into an alpha helix or fold into a beta pleated sheet
Tertiary structure
To coiled or folded chain of amino acids is often coiled and folded further. More bonds form between different parts of the polypeptide chain. For proteins made from a single polypeptide chain, the tertiary structure forms their final 3D structure
Quaternary structure
The way the polypeptide chains are assembled together eh haemoglobin is made from four polypeptide chins linked together
Globular protein
- Round and compact
- Soluble so easily transported in fluid
- Haemoglobin conjugated protein
- Insulin hormone by pancreas
Fibrous proteins
- Tough and rope shaped
- Insoluble and strong
- Structural proteins don’t react with much
Collagen
- Found in animal connective tissue- very strong molecule Minerals bind and make it a very strong molecule
Keratin
- Found in many external structures of animals such as skin and nails and horns
- It can either be flexible or hard or tough.
