biological molecules Flashcards
What is a monomer?
Monomers are the smaller units from which larger molecules are made
What is a polymer?
Polymers are molecules made from a large number of monomers joined together in a chain.
What are the examples for monomers?
Glucose, amino acid and nucleotide
What are the examples for polymers ?
Starch, glycogen, cellulose, protein, DNA and RNA
What are the 3 monosaccharides?
Glucose,Fructose and Galactose
What are the 3 disaccharides ?
Sucrose, Maltose and lactose
What are the 3 polysaccharides ?
Starch, cellulose and glycogen
What are the three different types of carbohydrates called?
Monosaccharides , disaccharides and polysaccharides
What is a carbohydrate?
Carbohydrates are molecules which consist only of carbon, hydrogen and oxygen and they are long chains of sugar units called saccharides.
Why is water such an important molecule and a major component of cells?
Water is a polar molecule due to uneven distribution of charge within the molecule
- the hydrogen atoms are more positive than the oxygen atom causing one end of the
molecule to be more positive than the other
It is a metabolite in metabolic reactions such as condensation and hydrolysis which are used in forming and breaking of chemical bonds
It is a solvent in which many metabolic reactions occur
It has a high heat specific capacity meaning that a lot of energy is required to warm
water up therefore minimising temperature fluctuations in living things therefore it acts as a Durier
It has a relatively large latent heat of vaporisation, meaning evaporation of water provides a cooling effect with little water loss
Strong cohesion between molecules enables effective transport of water in tube-like transport cells as the strong cohesion supports columns of water. As a result of strong cohesion the surtace tension at the water-air boundary is high
Maximum density of water is at 4 degrees - this means that ice is less dense than water and floats on top of it creating an insulating layer, this increases the chance of survival of organisms in large bodies o water as it prevents them from freezing
Water is incompressible therefore it provides good support
What are saturated lipids?
saturated lipids don’t contain any carbon-carbon double bonds
What are unsaturated lipids?
unsaturated iDids contain carbon-carbon
double bonds and melt at lower temperatures than saturated fats
What are triglycerides?
are lipids made of one molecule of glycerol and 3 fatty acids joined by ester bonds formed in condensation reactions
When do hydrolysis reactions take place?
Hydrolysis Reactions occurs when larger molecules are broken down into smaller molecules with the addition of water.
What is the test for reducing sugars?
Add Benedict’s reagent + heat and should produce a red/orange precipitate
What is the test for non-reducing sugars?
hydrochloric acid+ heat should produce a red/orange precipitate
What is the test for starch?
Add iodine should turn blue/black
What is the test for proteins?
Add sodium hydroxide should turn purple
What is the tests for lipids?
Add ethanol+water should turn cloudy white
What’s a covalent bond?
A covalent bond is the sharing of two or more electrons between two atoms
What is a condensation reaction?
A condensation reaction occurs when monomers combine together by covalent bonds to form polymers (polymerisation) or macromolecules (lipids) and water is removed
What is a hydrolysis reaction?
In the hydrolysis of polymers, covalent bonds are broken when water is added
What are Nucleic Acids?
Like carbohydrates, lipids and proteins, all nucleic acids contain the chemical elements C, H and O
However, all nucleic acids also contain N (nitrogen) in their bases and P (phosphorous) in the form of phosphate groups
