Water

Question 1

What is the most abundant compound on Earth?

Answer 1

Water

Question 2

What percentage of all living organisms does water make up?

Answer 2

60 to 95%

Question 3

What are the components of a water molecule?

Answer 3

Two hydrogen atoms covalently bonded to an oxygen atom

Question 4

What type of bonds form between water molecules?

Answer 4

Weak hydrogen bonds

Question 5

What is one role of water as a metabolite?

Answer 5

It is involved in condensation and hydrolysis reactions

Question 6

In which process is water a metabolic product?

Answer 6

Respiration

Question 7

What is one function of water as a solvent?

Answer 7

Transport of nutrients such as glucose in blood

Question 8

What does water help to remove from the body?

Answer 8

Excretory products such as urea and ammonia

Question 9

What property of water allows it to buffer temperature changes?

Answer 9

Relatively high heat capacity

Question 10

What effect do hydrogen bonds have on water’s temperature regulation?

Answer 10

They absorb heat energy before increasing temperature

Question 11

What is the latent heat of vaporisation of water?

Answer 11

It requires energy to break hydrogen bonds for evaporation

Question 12

How does water provide a cooling effect through evaporation?

Answer 12

It removes heat energy from the body or environment

Question 13

What internal support does water provide in plants?

Answer 13

Turgor pressure and support in xylem transport

Question 14

What allows insects to walk on water’s surface?

Answer 14

Surface tension due to cohesive forces between water molecules

Question 15

Fill in the blank: Water is not easily ______, providing support in non-woody plants.

Answer 15

compressed

Question 16

What provides buoyancy for aquatic organisms?

Answer 16

Water

Question 17

What is the cooling effect of sweat evaporation in animals attributed to?

Answer 17

High latent heat of vaporisation of water

Question 18

True or False: Water has a low heat capacity, allowing rapid temperature changes.

Answer 18

False

Question 19

What does water’s high heat capacity help to minimize in cells?

Answer 19

Increase in temperature due to biochemical reactions

Question 20

What are inorganic ions?

Answer 20

Ions that occur in solution in the cytoplasm and body fluids of organisms.

Question 21

What is the role of sodium ions?

Answer 21

Co-transport of glucose and amino acids across cell membranes.

Question 22

What is the role of iron ions?

Answer 22

Component of haemoglobin which transports oxygen.

Question 23

What is the role of hydrogen ions?

Answer 23

Important in determining pH and thus affecting protein structure and enzyme activity.

Question 24

What is the role of phosphate ions?

Answer 24

Important as a structural component of DNA, RNA, and ATP.

Question 25

Fill in the blank: Sodium ions are important in the _______ of glucose and amino acids across cell membranes.

Answer 25

co-transport

Question 26

True or False: Iron is not involved in oxygen transport.

Answer 26

False

Question 27

Fill in the blank: Hydrogen ions are important in determining _______.

Answer 27

pH

Question 28

List four types of inorganic ions mentioned.

Answer 28

* Sodium * Iron * Hydrogen * Phosphate

Question 29

What will you learn about inorganic ions throughout your A level?

Answer 29

Other roles of these ions.