1.8 inorganic ions

Question 1

Summary

Answer 1

Occur in solutions of the cytoplasm and body fluids of organisms

Some in high concentration and others in very low concentrations

Question 2

Ion 1

Answer 2

Phosphate PO43-

Attached to other molecules as a phosphate group:

E.g. in DNA nucleotides, enabling nucleotides to join together forming phosphodiester bonds

in ATP - bonds between these store / release energy

Question 3

Ion 2

Answer 3

Hydrogen H+

Maintain pH levels in the body
- too much H+ = acidic (low pH)

• too little H+ = alkali (high pH)
• affects rate of enzyme-controlled reactions as can cause enzymes to denature

Question 4

Ion 3

Answer 4

iron Fe2+

Component of haemoglobin which is contained in red blood cells

Transport oxygen around the body - oxygen temporarily binds to it, so it becomes Fe3+

Question 5

Ion 4 n

Answer 5

Sodium Na+

Co transport of glucose and amino acids across cell membranes

Involved in generating nerve impulses and muscle contraction