Biological Molecules Flashcards
What is a monomer
Small, single unit molecule which can be joined together to form polymer (building blocks)
What is a polymer
Large molecule made up of similar / identical monomers joined tufter
Condensation reaction
Joins two molecules together
Releases a water molecule
Forms a chemical bond
Hydrolysis reaction
Separates two molecules
Requires the addition of a water molecule
Breaks a chemical bond
What makes up carbohydrates
Carbon
Hydrogen
Oxygen
Monosacchaires
Monomers from which larger carbohydrates are made
Gluecose
Fructose
Galactose
Alpha Glucose
OH is at the bottom
Beta Glucose
OH is at the top
Disacharrides
Two monosacharides formed in a condensation reaction
Maltose
Alpha glucose + Alpha glucose
Sucrose
Alpha glucose + Fructose
Lactose
Alpha glucose + Galactose
Polysacchaires
More than two monomers formed together in a condensation reaction
Glycogen
Energy storage in animals
Polysaccharide of alpha glucose
How is the structure of glycogen related to its function
Branched - can be rapidly hydrolysed to release glucose for respiration
Large - can’t leave the cell
Insoluble - doesn’t affect WP
Starch
Energy store in plants
Structure - made from amylose (unbranched) and amylopectin (branched)
How the structure of starch is related to its function
Helical - compact for storage in cell
Large - can’t leave the cell
Insoluble - doesn’t affect WP
Celllose
Provides strength and support to cell walls
Long unbranched chains of beta glucose
How is the structure of cellulose related to its function
Long straight unbranched chain
Many hydrogen bonds link parallel strands to form microfibrils
H bonds are strong in high numbers
Provides strength and structural support to cell walls
What are the two types of sugar
Reducing
Non reducing
Benedicts test for reducing sugars
1) Add Benedicts reagent (blue) to sample
2) Heat in a boiling water bath
3) Positive = red precipitate
Benedicts test for non - reducing sugars
1) Add a few drops of dilute HCL (hydrolyse sugar into reducing sugar - monomer)
2) Heat in a boiling water bath
3) Neutralise with sodium bicarbonate
4) Add Benedicts and heat again
5) Non reducing sugar = red
Test for starch
Iodine
Positive - blue black colour
Water
Most abundant lipid on earth
Water is dipolar
Made from 2 hydrogen atoms and 1 oxygen atom
No overall charge
Negative and positive poles
Water and hydrogen bonding
Due to polarity (opposite charges) water molecules attract each other forming hydrogen bonds
Allows water to stick
Cohesion of water
The tendency of water molecules to stick together
Allows water to move up the xylem in plants
Specific heat capacity - water
Due to polarity and cohesion - a lot of energy needed to separate molecules
Requires a high energy to be heated
Acts as a buffer - makes aquatic environments more stable
Stays liquid for a long time as a lot of energy is needed to break the bonds
Hydrogen - Inorganic ion
Maintains pH in the body
Too much H+ = acidic (high pH)
Too little H+ = alkaline (low pH)
Affects rate of enzyme controlled reactions - enzyme can denature
Phosphate - Inorganic ion
Attached to other molecules in phosphate group
DNA nucleotides - nucleotides can join together to form phosphodiester bonds
ATP - bonds store/ release energy (between)
Iron - Inorganic ion
Component of haem group - haemoglobin
Transports 02 around the body
