Biological Molecules 1

Question 1

What is a polymer

Answer 1

Large complex molecules composed of long chains of monomers joined together

Question 2

What type of reaction forms polymers

Answer 2

Condensation reaction ( removal of a water molecule)

Question 3

What type of reaction breaks down polymers

Answer 3

Hydrolysis ( addition of a water molecule)

Question 4

What elements make up a carbohydrate molecule

Answer 4

Oxygen
Hydrogen
Carbon

Question 5

What are the monomers that carbohydrates are made from

Answer 5

Monosaccharides

Question 6

Give examples of some monosaccharides

Answer 6

Alpha glucose
Beta glucose
Fructose
Galactose

Question 7

What is a disaccharide

Answer 7

Two monomers joined together via a condensation reaction

Question 8

What bond forms between two monosaccharides

Answer 8

Glycosidic bonds

Question 9

Give examples of disaccharides and there monosaccharides

Answer 9

Alpha glucose + alpha glucose =Maltose
Alpha glucose + fructose =Sucrose
Alpha glucose + galactose =Lactose

Question 10

What is a polysaccharide

Answer 10

When more than two monosaccharides are joined together via a condensation reaction ,
Forming glycosidic bonds

Question 11

Give 3 examples of polysaccharides

Answer 11

Starch
Glycogen
Cellulose

Question 12

What is the structure and the functions of starch

Answer 12

Amylose
Structure = long unbranched chain of alpha glucose.
Coiled structure
Function = this makes it really compact and so is therefore a good storage molecule because it can fit in small spaces

Amylopectin
Structure = long branched chains of alpha glucose
Function = branched chains allow for enzymes to breach down the molecules easily because of the glycosidic bond is more exposed . Meaning glucose and be released more easily.

Insoluble in water so doesn’t affect water potential ,therefore is a good storage molecule.

Question 13

What is the structure and function of glycogen

Answer 13

Structure = a polysaccharide of alpha glucose with lots of side chains
Function= this means that enzyme’s can easily access the bonds to break them meaning it can be a quick real ease of energy .
It is also a very compact molecule which is good for storage.

Important energy store in animals.

Question 14

What is the structure and function of cellulose

Answer 14

Structure =long unbranched chain of beta glucose. Bonded together to form straight chains .
These straight chains are held together by hydrogen bonds forming microfibrils
Function =these strong fibres means that cellulose provide structural support for plants in the cell walls

Question 15

What is the test for starch

Answer 15

Iodine solution test

Positive =blue-black
Negative=browny-orange

Question 16

What are the main two types of lipids

Answer 16

Triglycerides
Phospholipids

Question 17

What molecules make up a triglyceride

Answer 17

One glycerol molecule
Three fatty acids molecules

Question 18

What is special about the fatty acid tails on triglycerides

Answer 18

They are hydrophobic so repel water

Question 19

What does the fatty acid tail make a triglyceride

Answer 19

Insoluble in water

Question 20

What are the two types of fatty acids

Answer 20

Saturated fatty acids
Unsaturated fatty acids

Question 21

What is a saturated fatty acid

Answer 21

When the R group of the fatty acid only contains single bonds

Question 22

How are triglyceride formed

Answer 22

Condensation reaction

Question 23

What bonds form between molecules in a triglyceride

Answer 23

Ester bonds

Question 24

What makes up a phospholipid

Answer 24

One glycerol molecule
Two fatty acid molecules
One phosphate group

Question 25

What is special about the phosphate group

Answer 25

It is hydrophilic ( attracts water )

Question 26

What is special about the fatty acid molecules

Answer 26

They are hydrophobic ( repel water )

Question 27

What is the main usage of triglyceride

Answer 27

Energy storage molecule Insoluble in water so they don’t effect water potential Hydrophobic tails face inwards

Question 28

What are the main properties of phospholipids

Answer 28

Make a phospholipids bilayer With hydrophobic tails inwards With hydrophilic heads facing outwards

Question 29

What is the test for lipids

Answer 29

Emulsion test Shake substances in a test tube with ethanol Then add to water Positive test = produced a milky emulsion

Question 30

What are the monomer of proteins

Answer 30

Amino acids

Question 31

What is formed when two amino acids join together

Answer 31

Dipeptide

Question 32

What are many amino acids bonded together known as ?

Answer 32

Polypeptide

Question 33

What is the general structure of an amino acid

Answer 33

A carboxyl group (COOH) an amine group (NH2) and a variable R group

Question 34

What reaction joins two amino acids together

Answer 34

Condensation reaction

Question 35

What bonds form between amino acids

Answer 35

Peptide bonds

Question 36

What is the primary structure of a protein

Answer 36

The basic sequence of amino acids in the polypeptide chain

Question 37

What is the secondary structure of proteins

Answer 37

When hydrogen bonds form between the amino acid chain , forming a basic shape , cooling into an alpha helix or folded into a beta pleated sheet

Question 38

What is the tertiary structure of a protein

Answer 38

The overall 3D shape of the protein where more bonds form between different sections of the of the polypeptide chain , Such as : Ionic bonds Hydrogen bonds Disulfide bridges

Question 39

What is the Quaternary structure of a protein

Answer 39

The way the 3D polypeptide chains are assembled together , the overall final 3D shape ( not all proteins have a quaternary structure , only if it contains more than one polypeptide chain )

Question 40

Give examples of proteins in the body

Answer 40

Enzymes Hormones Antibodies Structural proteins ( Keratin ) Transport proteins

Question 41

What is the test for proteins

Answer 41

Biuret test Add sodium hydroxide solution Then add copper sulfate solution Positive = purple