B1.1 Carbs and lipids

Question 1

Carbon contain four electrons

Answer 1

allowing them to form four covalent bonds with potential four other different atoms, e.g. methane (CH4).

Question 2

Covalent bonds are the strongest type of bond between atoms

Answer 2

Because of the stability of covalent bonds large molecules with many bonds can be formed.

Question 3

Monosaccharide

Answer 3

the simplest units of carbohydrates and the simplest form of sugar

Question 4

Glucose (monosaccharide)

Answer 4

• stable polar monosaccharide that is soluble in blood plasma and can be oxidised in cellular respiration.
• formula C6H12O6
  It forms a hexagonal ring (hexose)
• base unit for many polymers
• 5 of the carbons form corners on the ring with the 6th corner taken by oxygen

Question 5

Macromolecules

Answer 5

produced by condensation reactions that link monomers to form a polymer

Question 6

Polymers can be digested into monomers

Answer 6

by hydrolysis reactions that split water molecules to provide the –H and –OH groups necessary to produce monomers

Question 7

Galactose (monosaccharide)

Answer 7

• also a hexose sugar
  It has the same formula C6H12O6
  but is less sweet
• Most commonly found in milk, but also found in cereals

Question 8

Fructose (monosaccharide)

Answer 8

• another pentose sugar
• commonly found in fruits and honey
• It is the sweetest naturally occurring carbohydrate

Question 9

Polysaccharides

Answer 9

energy storage compounds that are compact and insoluble due to their large molecular size and coiling and branching during polymerisation

Question 10

Ribose (monosaccharide)

Answer 10

• pentose sugar, it has a pentagonal ring
• It forms the backbone of RNA
• Deoxyribose differs and forms the backbone of DNA

Question 11

monosaccharides are

Answer 11

monomers of polysaccharides

Question 12

glucose + glucose ->

Answer 12

-> (condensation) Maltose + water

Question 13

Disaccharide

Answer 13

a molecule formed by condensation reactions between 2 monosaccharides

Question 14

Maltose (Disaccharide)

Answer 14

• glucose + glucose (C12H22O11)
• source : hydrolyzed starch

Question 15

if you eat starch (past, bread)..

Answer 15

long starch chain in the digestive system amylase break down → 2 molecules of maltose

Question 16

Lactose (Disaccharide)

Answer 16

• (C12H22O11) is most commonly found in milk
• glucose + galactose

Question 17

Sucrose (Disaccharide)

Answer 17

• known as table sugar
• glucose + fructose
• source : plants

Question 18

Maltose synthase ->

Answer 18

glycosidic bond

Question 19

A ribosome condenses two amino acids

Answer 19

into a dipeptide forming a peptide bond (+ water)

Question 20

polysaccharide

Answer 20

• polymers more than two molecules
• very long and maybe branched

Question 21

glycosidic bond

Answer 21

can be 1-4 or 1-6 carbon links

Question 22

starch forms and how?

Answer 22

• Amylose and Amylopectin

Question 23

Starch is made

Answer 23

by linking together α-glucose molecules (condensation reaction)
-> curved

Question 24

amylose (starch)

Answer 24

• chain of α-glucose (1-4 glycosidic bond)
• unbranched and forms a helix
• coil structure

Question 25

amylopectin (starch)

Answer 25

• branched → more globular shape
• allow to form more complex 3D structure for efficient storage of glucose

Question 26

Starch (polysaccharide)

Answer 26

• only made by plant cells
• hydrophilic but are too large to be soluble in water
• temporary energy storage

Question 27

Glycogen (polysaccharide)

Answer 27

• made from repeating glucose subunits (alpha 1-4 and 1-6)
• branched & coil
• made by animals and also some fungi