Biological molecules - 2

Question 1

What do carbohydrates consist of?

Answer 1

C, H, O

Question 2

What do Lipids consist of?

Answer 2

C, H, O

Question 3

What do proteins consist of?

Answer 3

C, H, O, N, S

Question 4

What do Nucleic acids consist of?

Answer 4

C, H, O, N, P

Question 5

Define metabolism

Answer 5

The sum total of all the chemical reactions that take place in an
organism.

Question 6

What are anabolic reactions

Answer 6

Building larger molecules from smaller ones

Question 7

What are catabolic reactions?

Answer 7

Breaking larger molecules into smaller ones

Question 8

What is a monomer?

Answer 8

A monomer is a single molecule
Many monomers make a polymer

Question 9

What is a condensation reaction?

Answer 9

• a water molecule is released
• A new covalent bond is formed
• A larger molecule is formed

Question 10

What is a hydrolysis reaction?

Answer 10

• a water molecule is used
• A covalent bond is broken
• Smaller molecules are formed

Question 11

What are the properties of water that make it special?

Answer 11

• High specific heat capacity
• High latent heat of evaporation
• hydrogen bonds makes ice form a lattice
• Effective solvent
• Cohesion
• Adhesion
• Surface tension
• Transparent

Question 12

Why is a high latent heat of evaporation useful

Answer 12

Evaporation is an efficient cooling mechanism

Question 13

Why is a high specific heat capacity useful

Answer 13

Thermally stable environment for aquatic organisms

Question 14

Why are hydrogen bonds useful in water

Answer 14

Hydrogen bonds make the ice form a lattice when it
solidifies (expands)

Ice is less dense than water = it floats

Water beneath ice is insulated

Aquatic organisms under the ice do not freeze / can still
swim

Provides a habitat

Question 15

Why is water an effective solvent

Answer 15

Medium for enzyme controlled reactions

Nitrates etc can be taken up by plants through their roots

Question 16

Why is adhesion and cohesion useful

Answer 16

Eg cohesion of water molecules helps transpiration stream

Eg adhesion of water to lignin in xylem

Question 17

Why is surface tension important

Answer 17

Provides a habitat for invertebrates

Question 18

Why is water being transparent useful?

Answer 18

Allows underwater plants to photosynthesis

Question 19

What are the functions of carbohydrates?

Answer 19

• Energy source
• Energy store
• Structure
• Form parts of larger molecules

Question 20

What are monosaccharides and give examples?

Answer 20

• Simple sugars
• E.G glucose, fructose and ribose

Question 21

What are disaccharides and give examples?

Answer 21

• These are double sugars formed from two monosaccharides
• E.G maltose, sucrose, lactose

Question 22

What are polysaccharides and give examples?

Answer 22

• These are large molecules formed
  from many monosaccharides
• E.G. starch, glycogen,
  cellulose

Question 23

What are the 3 types of monosaccharides

Answer 23

• Triose
• Pentose
• Hexose

Question 24

What are the two structural isomers of glucose

Answer 24

• Alpha glucose and beta glucose

Question 25

What are three differences between amylose and amylopectin

Answer 25

- Amylopectin has side branches whereas amylose doesn't - Amylopectin has 1-6 glycosidic bonds where as amylose only has 1-4 glycosidic bonds - Amylose is soluble where as amylopectin isn't

Question 26

Why is glycogen a good storage molecule

Answer 26

- Densely packed so more ATP molecules can be stored closely together - Has many side branches which allow efficient release of energy - It is insoluble so it cannot dissolve and affect water potential within cells

Question 27

Which glucose is found in cellulose?

Answer 27

beta glucose

Question 28

What are 3 examples of lipids?

Answer 28

- Triglycerides - Cholesterol - Steroids - Phospholipids

Question 29

What is the difference between a fat and an oil?

Answer 29

Fats are solid at room temperature where as lipids are liquid at room temperature

Question 30

What are the functions of lipids?

Answer 30

- Energy source - Energy store - Biological membranes - Insulation - Buoyancy - Protection - Waterproofing

Question 31

What makes up triglycerides?

Answer 31

Glycerol and three fatty acid tails

Question 32

What makes a fatty acid unsaturated?

Answer 32

If it contains a C=C double carbon bond

Question 33

What bond forms between the glycerol and the fatty acids?

Answer 33

An ester bond

Question 34

What is the structure of cholesterol

Answer 34

- 4 Carbon rings - Small, narrow molecule - Hydrophobic

Question 35

What is the difference between the structure of a phospholipid and a triglyceride?

Answer 35

- Triglycerides have 3 fatty acid tails where as phospholipids only have 2 - Phospholipids have a phosphate group attached to the glycerol head where as triglycerides don't - Triglycerides have a hydrophobic head where as phospholipids have a hydrophilic