Biological Molecules

Question 1

What is a monomer

Answer 1

Small, single unit molecule which can be joined together to form polymer (building blocks)

Question 2

What is a polymer

Answer 2

Large molecule made up of similar / identical monomers joined tufter

Question 3

Condensation reaction

Answer 3

Joins two molecules together
Releases a water molecule
Forms a chemical bond

Question 4

Hydrolysis reaction

Answer 4

Separates two molecules
Requires the addition of a water molecule
Breaks a chemical bond

Question 5

What makes up carbohydrates

Answer 5

Carbon
Hydrogen
Oxygen

Question 6

Monosacchaires

Answer 6

Monomers from which larger carbohydrates are made
Gluecose
Fructose
Galactose

Question 7

Alpha Glucose

Answer 7

OH is at the bottom

Question 8

Beta Glucose

Answer 8

OH is at the top

Question 9

Disacharrides

Answer 9

Two monosacharides formed in a condensation reaction

Question 10

Maltose

Answer 10

Alpha glucose + Alpha glucose

Question 11

Sucrose

Answer 11

Alpha glucose + Fructose

Question 12

Lactose

Answer 12

Alpha glucose + Galactose

Question 13

Polysacchaires

Answer 13

More than two monomers formed together in a condensation reaction

Question 14

Glycogen

Answer 14

Energy storage in animals

Polysaccharide of alpha glucose

Question 15

How is the structure of glycogen related to its function

Answer 15

Branched - can be rapidly hydrolysed to release glucose for respiration
Large - can’t leave the cell
Insoluble - doesn’t affect WP

Question 16

Starch

Answer 16

Energy store in plants

Structure - made from amylose (unbranched) and amylopectin (branched)

Question 17

How the structure of starch is related to its function

Answer 17

Helical - compact for storage in cell
Large - can’t leave the cell
Insoluble - doesn’t affect WP

Question 18

Celllose

Answer 18

Provides strength and support to cell walls

Long unbranched chains of beta glucose

Question 19

How is the structure of cellulose related to its function

Answer 19

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

Question 20

What are the two types of sugar

Answer 20

Reducing

Non reducing

Question 21

Benedicts test for reducing sugars

Answer 21

1) Add Benedicts reagent (blue) to sample
2) Heat in a boiling water bath
3) Positive = red precipitate

Question 22

Benedicts test for non - reducing sugars

Answer 22

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

Question 23

Test for starch

Answer 23

Iodine

Positive - blue black colour

Question 24

Water

Answer 24

Most abundant lipid on earth

Question 25

Water is dipolar

Answer 25

Made from 2 hydrogen atoms and 1 oxygen atom No overall charge Negative and positive poles

Question 26

Water and hydrogen bonding

Answer 26

Due to polarity (opposite charges) water molecules attract each other forming hydrogen bonds Allows water to stick

Question 27

Cohesion of water

Answer 27

The tendency of water molecules to stick together | Allows water to move up the xylem in plants

Question 28

Specific heat capacity - water

Answer 28

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

Question 29

Hydrogen - Inorganic ion

Answer 29

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

Question 30

Phosphate - Inorganic ion

Answer 30

Attached to other molecules in phosphate group DNA nucleotides - nucleotides can join together to form phosphodiester bonds ATP - bonds store/ release energy (between)

Question 31

Iron - Inorganic ion

Answer 31

Component of haem group - haemoglobin | Transports 02 around the body