Carbs, lipids and proteins

Question 1

What are four functions of carbohydrates

Answer 1

.As an energy source( glucose in respiration)
.Energy store
.Structural support
.Part of other importnsnt molecules (nucleic acids)

Question 2

What are the three groups of carbohydrates

Answer 2

.monosaccharides
.Disaccharides
.Polysaccharides

Question 3

Name 3 monosaccharides

Answer 3

Glucose
Fructose
Galactose

Question 4

Name 3 disaccharides and what their made of

Answer 4

Sucrose- glucose+fructose
Lactose-glucose +galactose
Maltose-glucose + glucose

Question 5

Name 4 polysaccharides

Answer 5

• Starch
• Glycogen
• Cellulose
• Chitin

Question 6

Name 3 qualities of a monosaccharide

Answer 6

• Soluble
• Sweet
• Form crystels

Question 7

Functions of monosaccharides

Answer 7

Source of energy
Building blocks for larger molecules
Intermediate In reactions
Constituents of nucleotides

Question 8

What bond forms a disaccharide

Answer 8

Glycosidic

Question 9

How are glycosidic bonds formed

Answer 9

Through condensation reactions , where water is lost and oxygen bonds between two monomers

Question 10

What’s the opposite reaction to co sensation and what happens in it

Answer 10

Hydrolysis

Water is added into a reaction

Question 11

What are polysaccharides

Answer 11

Large complex polymers

Formed by a large chain of glycosidic bonded monosaccharides

Question 12

Why is glucose stored as starch or glycogen instead of individual monosaccharides

Answer 12

Glucose is soluble

So would affect a cells osmosis affect and factors

Question 13

Qualities of starch

Answer 13

Insoluble so has no osmosis effect
Cannot diffuse out of a cell
Compact molecule
Carries a lot of energy in c-c and c-h bonds

Question 14

What are the two types of chains that make up starch and what are their qualities

Answer 14

Amylose
Linear, unbranched molecule which alpha 1 -4 glycosidic bonds for,OMG between c1 and c4
They can coil
Amylopectin
Has chains of glucose joined with a 1-4 glycosidic bond
Cross linked with a 1-6 glycosidic bond and fit inside amylose
Branches are formed

Question 15

Name two other poly saccharides and explain their differences

Answer 15

Glycogen
Cellulose
Glycogen is used for storage whereas cellulose is for structure cellulose comprised of beta glucose which flipped each monomer 180 degrees to its previous one

Question 16

Why is glycogen more branched than amylopectin

Answer 16

Glycogen has shorter a 1-4 bonds

Question 17

What do lipids comprise of

Answer 17

Oxygen, carbon, hydrogen

Question 18

Are lipids polar or non polar

Answer 18

Polar

Question 19

Are lipids soluble or Insoluble in water

Answer 19

Insoluble

Question 20

How are triglycerides formed

Answer 20

By one glycerol molecule and three fatty acid molecules which are joined by a condensation reaction

Question 21

What bonds are formed through lipid condensation reactions

Answer 21

Ester bonds

Question 22

What is a saturated lipid

Answer 22

A lipid that every carbon bond is maximised and there are no c=c double bonds

Question 23

What an unsaturated lipid

Answer 23

There’s a c=c carbon bonds which creates a kink in the uniform structure
This spreads molecules out more so therefore has more room to move to has a lower melting point

Question 24

Why do unsaturated lipids have a lower melting point

Answer 24

Unsaturated fatty acids have a kinks which spreads out the molecules more which means the molecules have more room to move and break free of the structure

Question 25

What is a phospholipid

Answer 25

A special type of lipid that has one end that is soluble in water
The phosphate part being hydrophilic and the lipid tails are hydrophobic
They are in cell membranes and allows water to move in and out

Question 26

What do proteins consist of

Answer 26

Hydrogen
Oxygen
Carbon
Nitrogen

Question 27

What is the basic of a protein

Answer 27

Amino acids

Question 28

What 5 sections do amino acids contain

Answer 28

Amino group (N and H2)
An R group which is individual to each amino acid
Carboxyl group (c=ooh)
Central carbon atom

Question 29

How is an amino acid a zwitterion

Answer 29

Amino group gains a hydrogen io. And becomes positively charged
The carboxyl group loses a hydrogen ion and becomes negatively charged

Question 30

What bonds are formed between two amino acids

Answer 30

Peptide bonds

Question 31

What are peptide bonds

Answer 31

Amino group of one amino acid reacts with another carboxyl group with the elimination of water
This creates a dipeptide

Question 32

What a the primary structure of protein

Answer 32

Amino acids in a polypeptide chains

Question 33

What’s the secondary structure of protein

Answer 33

Hydrogen bonds between =O of carboxyl groups and the - H on the amino group
This makes the long peptide chain to be twisted into a helix ( alpha helix) or a less common beta pleated sheets

Question 34

What’s the tertiary structure of a protein

Answer 34

Alpha helix of the secondary protein is folded and twisted to give more complex , compact 3-D structure

Question 35

What is the tertiary structure maintained by

Answer 35

Hydrogen bonds 
Ionic bonds 
Disulphides bonds
Peptide bonds 
And hydrophobic interactions

Question 36

What’s the quartary structure of a protein

Answer 36

Only happens in some proteins
Sometimes ,Polypeptide chains are not functional unless they act as a combination
Multiple chains bind together

Question 37

What’s meant by globular when describing proteins

Answer 37

Are compact and folded into spherical molecules

This makes them soluble in water

Question 38

Functions of globular proteins

Answer 38

Enzymes
Antibodies
Plasma, proteins and hormones
Haemoglobin

Question 39

What’s meant by a fiberous protein

Answer 39

Long protein molecules which are insoluble in water

an example is proteins in muscle

Question 40

What does a single fiberous protein consist of

Answer 40

3 identical polypeptide chains twisted around each other which are linked by hydrogen bonds which makes them stable