T1:Biological molecules

Question 1

What are monomers and polymers?

Answer 1

Monomers are small, single units that can join together to form polymers, which are large, complex molecules made up of monomers.

Question 2

What is a condensation reaction?

Answer 2

A condensation reaction is a chemical process where two molecules combine to form a larger molecule, releasing a small molecule, often water.

Question 3

What is a hydrolysis reaction?

Answer 3

A hydrolysis reaction is a chemical process that breaks down a compound by adding water, resulting in the separation of the compound.

Question 4

What is metabolism?

Answer 4

•sum of all chemical reactions that occur within a living organism to maintain life

Question 5

What does ‘life based on carbon’ mean?

Answer 5

‘Life based on carbon’ means that carbon is the fundamental building block of the molecules that make up living organisms.

Question 6

What are monosaccharides, amino acids, and nucleotides?

Answer 6

Monosaccharides are simple sugars, amino acids are the building blocks of proteins, and nucleotides are the basic units of nucleic acids.

Question 7

What’s the general formula of monosaccharides?

Answer 7

The general formula of monosaccharides is (CH2O)n, where n is typically 3 or more.

Question 8

What are some examples of monosaccharides?

Answer 8

• glucose
•fructose
•galactose

Question 9

What are the isomers of glucose and what do they look like?

Answer 9

The isomers of glucose include alpha-glucose and beta-glucose, which differ in the arrangement of the hydroxyl group on the first carbon.

Question 10

What is the test for reducing sugars?

Answer 10

•Benedict’s solution
•presence of reducing sugars turns brick red

Question 11

What are the three disaccharides?

Answer 11

glucose +fructose=sucrose
glucose + galactose =lactose
glucose+glucose=maltose.

Question 12

What bonds form between monosaccharides?

Answer 12

•Glycosidic bonds
•during the process of condensation

Question 13

What is a test for non-reducing sugars ?

Question 14

What are polysaccharides?

Answer 14

polymers formed by combining together many monosaccharides joined by glycosidic bonds formed via condensation reaction.

Question 15

what is the test for starch?

Answer 15

Iodine to a blue-black .

Question 16

What is starch?

Answer 16

•alpha glucose polysaccharide found in plants
• form of small grains,a major energy source
•(branched or unbranched) chains linked by glycosidic bonds.

Question 17

What is the roles and structure of starch?

Answer 17

Its main role is energy storage. Its structure is: insoluble so it doesn’t effect water potential , large and insoluble so it wont diffuse out of cells, compact so a lot can be stored in a small place, when hydrolysed forms alpha glucose which is easily transported for respiration and branched ends can be acted on simultaneously by enzymes so monomers are released rapidly.

Question 18

What is glycogen?

Answer 18

Glycogen is the main carbohydrate store for animals made with alpha glucose and similar structure to starch but shorter more highly branched chains.

Question 19

what is glycogens structure?

Answer 19

Glycogen is insoluble so is not drawn out via osmosis or diffuse out cells, compact so alot stored in a small place, more highly branched so more enzymes can break it down to form glucose for respiration for animals as the have a higher metabolic rate as they are more active.

Question 20

What is cellulose?

Answer 20

cellulose is a polymer of beta glucose in straight unbranched chains with hydrogen bonds forming cross linkages between adjacent chains.

Question 21

What is cellulose structure in a plant ?

Answer 21

cellulose is molecular chains run parallel to eachother and crossed linked by hydrogen bonds which add collective strength.
It provides rigidity and prevents cell bursting from osmosic pressure , cellulose molecules group together forming microfibrils which are then arranged in parallel groups (fibres) which provides more strength.

Question 22

what are the characteristics of lipids?

Answer 22

-contain carbon hydrogen oxygen
-insoluble in water
-soluble in organic solvents

Question 23

what are the main groups of lipids?

Answer 23

-triglycerides (fats and oils)
-phospholipids

Question 24

what are the roles of lipids?

Answer 24

-in the cell membranes they contribute to flexibility
-source of energy when oxidised
-waterproofing as they are insoluble
-insulation as fats are slow conductors of heat
-protection as its stored around delicate organs

Question 25

what are triglycerides?

Answer 25

three fatty acids with a combined glycerol in condensation reaction. fatty acids (-COOH and hydrocarbon chain) determine the triglyceride

Question 26

How does structure of triglyceride relate to its properties ?

Answer 26

-high ratio of C-H bonds which are a good store of energy -low mass to energy ratio (alot of energy in a small mass) -large , non-polar so they are insoluble in water

Question 27

What are phospholipids ?

Answer 27

-glycerol molecule , 2 fatty acids and a phosphate molecule (hydrophilic) -hydrophobic tail (fatty acid) -hydrophilic head (phosphate) so it is polar

Question 28

how does phospholipids relate to its structure?

Answer 28

-polar molecules so in aqueous environments phospholipids form a bilayer resulting in a hydrophobic barrier -phospholipids structure allows it to form glycolipids by combining with carbohydrates important for cell recognition.

Question 29

whats the test for lipids ?

Answer 29

-emulsion test -add ethanol and shake producing a cloudy white

Question 30

what is an amino acid and its structure?

Answer 30

-monomer units which form polypeptides (which form proteins) - a central carbon attached to : an amino group(NH2), carboxyl group (COOH) , hydrogen atom (H) and R side group .

Question 31

How are peptide bonds formed?

Answer 31

Condensation reaction by the removal of the -OH from COOH and -H from amino acids forming peptide bonds.

Question 32

what are the diffrent structure of proteins?

Answer 32

- Primary structure: amino acids joining by polymerisation forming polypeptides which determines shape and function -Secondary structure: hydrogen bonds form causing the long chain to be twisted into 3D shape called alpha helix or beta pleated sheet -Tertiary structure: a helix fold more forming more bonds like ionic bonds, hydrogen bonds and disulfide bridges . -Quaternary structure

Question 33

what is the test for proteins?

Answer 33

Biuret test which detects peptide bonds should turn purple

Question 34

what is an enzyme ?

Answer 34

Enzymes are globular proteins that act as a catalyst without being used up.

Question 34

what can effect the way an enzyme works?

Answer 34

- temperature -pH( alters the charges of the amino acids) too high or low enzyme will denature

Question 34

what is an enzymes structure/function ?

Answer 34

-active site made up of a small amount of amino acids -acts on substrate to form enzyme-substrate complex

Question 35

What are enzyme inhibitors?

Answer 35

They directly or indirectly interfere with the function of the active site to reduce its activity.

Question 36

What are the two types of enzyme inhibitors ?

Answer 36

-competitive inhibitors which have a similar shape to the substrate which allows them to occupy the active site. -non-competitive inhibitors which attach to a binding site which is not the active site to alter the shape of the enzyme.