Module 2.2 - Biological Molecules

Question 1

What are the inorganic cations involved in biological processes?

Answer 1

• Calcium, Ca2+
• Sodium, Na+
• Potassium, K+
• Hydrogen, H+
• Ammonium, NH4+

Question 2

What are the inorganic anions involved in biological processes?

Answer 2

• Nitrate, NO3-
• Hydrogencarbonate, HCO3-
• Chloride, Cl-
• Phosphate, PO4 3-
• Hydroxide, OH-

Question 3

How are calcium ions, Ca2+, used in biological processes?

Answer 3

• Increases rigidity of bone, teeth + cartilage + is a component of the exoskeleton of crustaceans
• Important in clotting blood + muscle contraction
• Activator for several enzymes e.g. lipase, ATPase, cholinesterase
• Stimulates muscle contraction + regulates transmission of nerve impulses
• Regulates permeability of cell membranes
• Important for cell wall development in plants, + formation of middle lamella between cell walls

Question 4

How are sodium ions, Na+, used in biological processes?

Answer 4

• Involved in regulation of oncotic pressure, control of water levels in body fluid + maintenance of pH
• Affects absorption of carbohydrate in the intestine + water in the kidney
• Contributes to nervous transmission + muscle contraction
• Constituent of vacuole in plants which helps maintain turgidity

Question 5

How are potassium ions, K+, used in biological processes?

Answer 5

• Involved in control of water levels in body fluid + maintenance of pH
• Assists active transport of materials across the cell membrane
• Involved in synthesis of glycogen + protein + breakdown of glucose
• Generates healthy leaves + flowers in flowering plants
• Contributes to nervous transmission + muscle contraction
• Component in vacuoles in plants, helping maintain turgidity

Question 6

How are hydrogen ions, H+, used in biological processes?

Answer 6

• Involved in photosynthesis + respiration
• Involved in transport of O2 + CO2 in the blood
• Involved in regulation of blood pH

Question 7

How are ammonium ions, NH4+, used in biological processes?

Answer 7

• A component of amino acids, proteins, vitamins + chlorophyll
• Some hormones are made of proteins e.g. insulin
• An essential component of nucleic acids
• Involved in maintenance of pH in the human body
• A component of the nitrogen cycle

Question 8

How are nitrate ions, NO3-, used in biological processes?

Answer 8

• A component of amino acids, proteins, vitamins + chlorophyll
• An essential component of nucleic acids
• Some hormones are made of proteins, which contain nitrogen e.g. insulin
• A component of the nitrogen cycle

Question 9

How are hydrogencarbonate ions, HCO3-, used in biological processes?

Answer 9

• Involved in regulation of blood pH

- Involved in transport of CO2 into + out of the blood

Question 10

How are chloride ions, Cl-, used in biological processes?

Answer 10

• Helps production of urine in the kidney + maintaining water balance
• Involved in transport of CO2 in + out of the blood
• Regulates Hb’s affinity for O2 rough allosteric effects on Hb molecule
• Involved in regulation of blood pH
• Used to produce HCl in the stomach

Question 11

How are phosphate ions, PO4 3-, used in biological processes?

Answer 11

• Increases rigidity of bone, teeth + cartilage + is a component of exoskeleton of crustaceans
• Component of phospholipids, ATP, nucleus acids + several important enzymes
• Involved in regulation of blood pH
• Helps root growth in plants

Question 12

How are hydroxide ions, OH-, used in biological processes?

Answer 12

-Involved in regulation of blood pH