Module 2.1.2 Biological Molecules Brewer Flashcards
What is a monomer?
A small molecule that is one of the units bonded to form a polymer
What is a polymer?
A large molecule made up of many repeating molecules covalently bonded together
What is a polar molecule?
A molecule with regions of negative charge and positive charge
What is hydrogen bonding ?
Relatively weak interaction which break and reform between the constantly moving water molecules
Details of water being a liquid
-Hydrogen bonds continually break and reform
-hydrogen bonds make it difficult for molecules to escape and become a gas so more energy is required to do so
- low viscosity so can flow easily
Why does ice float ?
1) water becomes more dense as it cools until 4C-0C
2)At this temp the polar nature causes the molecules to align themselves
3) due to less kinetic energy hydrogen bonds form up and expand forming a lattice structure with empty space making ice low density.
What is the arrangement of ice ?
Tetrahedral arrangement
Why is water a good solvent?
-polar so attracts to another polar substance
- the water molecules rearrange around the positive ion so that the partially negative region on the oxygen atom is fully surrounding the ion as opposites attract then making the ion saturated and fully dissolved.
-opposite for - ions . partially + regions in hydrogen
What is cohesion?
Hydrogen bonds between the molecules pull them towards eachother so they stick together
What is surface tension ?
Between the air and the water the cohesion between the molecules provide surface tension as the hydrogen bonds pull the molecules towards the surface
Why does water have a ^ SHC
-hydrogen bonds absorb alot of energy
- water doesn’t experience rapid temperature change
Why does water have high specific latent heat if vaporisation?
-a lot of energy is needed to break hydrogen bonds
- when water evaporates latent heat of vaporisation helps the molecules to break away and become gas
- a lot of energy needed = high SLHOV
Water as a reactant
-photosynthesis
- hydrolysis
-doesn’t draw on its polarity
What are lipids made of ?
-Carbon
-hydrogen
-oxygen
What are carbohydrates made of?
-carbon
-hydrogen
-oxygen
What are proteins made of ?
-carbon
-hydrogen
-oxygen
-nitrogen
-sulphur
What are nucleic acids made of?
-carbon
-hydrogen
-oxygen
-nitrogen
-phosphorus
Mass number
The MASSive number
How many bonds can carbon form ?
4
How many bonds can nitrogen form ?
3
How many bonds can oxygen form ?
2
How many bonds can hydrogen form ?
1
What is calcium required for (cation)?
-nerve impulses
-muscle contractions
What is sodium required for (cation)?
-nerve impulses
-kidney function
What is potassium required for? (cation)
-nerve impulses
-stomata
How many amino acids are need to create a protein?
20
What is a condensation reaction?
MAKING polymers
A chemical reaction where two molecules are joined together through covalent bonding forming a larger molecule and a molecule of water
What is hydrolysis?
BREAKING polymers
A chemical reaction where the covalent bond is broken when you add a water molecule, separating the two molecules
Where do hydrolysis reaction occur?
-maltose
-sucrose
-lacyose
What is covalent bonding?
-between two non metals
-share electrons
What is ionic bonding ?
-atoms are gained or lost
-metal and non metal
Properties of a covalent bond
1) strong
2) don’t break and reform easily
3) useful to make polymers
4) attraction WITHIN the molecule
Properties of hydrogen bond
1) relatively weak
2) break and reform easily
3) always invoked hydrogen
4) attraction BETWEEN molecules
What are the 2 carb groups?
Sugars
Starch
Describe sugars
-one or two units
1 unit -> monosaccharide
2 unit -> disaccharide
Describe starch
-long , large storage
-many units
-polysaccharide
General formula of monosaccharides
(CH2O)n
What are carbs for?
-act as an energy source and support
-function is related to structure
-contain carbon, oxygen, hydrogen
General formula of carbohydrates?
Cx(H2O)y
What’s an isomer ?
Molecules that have the same molecular formulas, but different arrangement of atoms
How is glucose related to its function of energy ?
-it makes it soluble -> can easily be transported
-it’s chemical bonds contain a lot of energy
What type of saccharide is glucose m?
Hexose monosaccharide
What do the hydrogen bonds between the hydroxyl groups and water molecules allow glucose to be ?
Insoluble I’m non polar solvents
How are disaccharides formed ?
-condensation reaction
What’s the bond formed between 2 monosaccharides to form a disaccharide?
-glycosidic bond
What is a glycosidic bond ?
A covalent bond formed when 2 carbohydrates are joined by a condensation reactionn
How is maltose formed?
- 2 alpha glucose molecules are joined by an alpha 1-4 glycosidic bond
How is sucrose formed ?
Isomer of glucose
Glucose and fructose join by an alpha 1-4 glycosidic bond
-alpha and beta
What are polysaccharides made of one kind of monomer called ?
Homopolysaccharides
What are polysaccharides made of more than one type of monomer called?
Heteropolysaccharides
What is starch ?
-a polymer of alpha glucose molecules with glycosidic bonds linking the molecules together
What is the formation of starch like?
-coiled up into a spring
-the shape of the monomer and angle the glycosidic bonds joking forms a 1-4 glycosidic bond
What are the 2 molecules of starch?
-Amylose
-amylopectin
Key features of amylose
-un branched chain of alpha glucose
-angles of glycosidic bonds give it a coiled structure ->compact hood for storage
Key features of amylopectin
-long, branched chasing of alpha glucose-> allows enzymes to break down the molecule to get at the glycosidic bonds so glucose can be released quickly
-better
What are plastids in starch ?
The way starch is stored -> as intracellular starch grains in organelles (plastids)
-membrane bound
-plant cells
Is starch soluble ?
No
-insoluble ->non polar
Why is starch insoluble?
-so it doesn’t cause water to enter cells by osmosis causing them to swell
What is glycogen ?
-main energy store in animals
-animals store excess glucose as glycogen
Structure of glycogen
-lots of side branches -> stored glucose can be released quickly
-compact -> storage
-alpha 1-6 glycosidic bonds
Glycogen vs starch
-Glycogen is less dense and more soluble than starch
-glycogen is broken down more rapidly -> shows animals have a higher metabolic requirements than plant
Structure of cellulose
-beta glucose joined by glycosidic bonds
-unbranched chains (straight cellulose chains)
-molecules flip in an alternating pattern due to the position of the -OH and -H group at C1
How are cellulose chains linked together?
-by hydrogen bonds
-form strong fibres (microfibrils) due to high number of -OH on the outside chains
How are macrofibres formed (cellulose)
Bundles of microfibrils are cross linked by hydrogen bonds
Why is cellulose used in cell walls?
-strong fibres provide structural support that’s stable
What are lipids?
-Macromolecules
-contain: carbon, hydrogen and oxygen
Are lipids soluble ?
No
-insoluble in water as they are not polar and don’t attract water molecules (hydrophobic )
-DO dissolve in alcohol
What are the three types of lipids ?
1) triglycerides
2)phospholipids
3)cholesterol
What’s a macromolecule?
-very large , organic molecule