, Topic 1: The chemistry of life
Glossary
Term Definition
Import Give or take animal food.
Reagent Substance that identifies chemical reactions.
Immiscible Do not mix with water.
Luminous Let light through.
Helix Three-dimensional spiral shape.
Eutrophication Excess nutrients in water causes oxygen deficiency.
Enzyme Protein that accelerates chemical reactions.
Inorganic compounds
• Examples: water, oxygen, carbon dioxide.
• Water is important for: Transport, dissolving substances, temperature control.
• Mineral elements:
o For humans: Na, K, Ca, P, Fe, I.
o For plants: Macro - N, P, K, Ca, Mg, S | Micro - B, Cu, Cl, Mn, Mo, Zn.
Fertiliser and leaching
• Provide plants with nutrients.
• Leaching: when nutrients such as phosphate leach out.
• Result: Eutrophication - aquatic life is dying.
Organic compounds
• Carbohydrates: C, H, O - source of energy.
• Monosaccharides: glucose.
• Disaccharide: maltose.
• Polysaccharides: starch, glycogen.
• Tests:
o Starch: Positive - blue-black.
o Benedict/Fehling for glucose: Positive - red/orange.
Copyright © The Teacher's Pet Life Sciences Grade 10 (Via Afrika) Page 2 of 31
, Lipids (fats and oils)
• Consists of glycerol + fatty acids.
• Saturated (lard) vs. unsaturated (olive oil).
• Functions:
o Structure of cell membranes.
o Energy storage.
o Insulation and protection.
o Waterproofing in plants.
• Tests:
o Ether test: Positive - oil mark.
o Water test: Positive - does not mix with water.
Proteins
• C, H, O, N (+ sometimes S, Fe, P).
• Structures:
o Primary → order.
o Secondary → folding.
o Tertiary → 3D form.
o Quaternary → several chains.
• Tests:
o Millon: burgundy.
o Biuret: violet/purple.
• Factors affecting structure: temperature, pH, salt concentration.
Enzymes
• Specialized proteins.
• Function as biological catalysts.
• Optimum conditions: temperature and pH.
• Examples:
o Amilase - starch.
o Protease - proteins.
o Lipase - fats.
Nucleic acids
• DNA – stores genetic code.
• RNA - helps to make proteins.
Vitamins
• Essential for metabolism.
• Deficiency Diseases:
o A - night blindness.
o B - beriberi, pellagra.
o C - Scurvy.
o D - rickets.
o E - Nerve problems.
Copyright © The Teacher's Pet Life Sciences Grade 10 (Via Afrika) Page 3 of 31
, Balanced diet
• Include all the most important nutrients.
• Energy intake must correspond to energy consumption.
• 1g fat = 9 calories | 1g of protein or carbohydrate = 4 calories.
• ADH (Recommended Dietary Amount) shows how many nutrients a person needs daily.
Malnutrition
• Causes: poverty, environment, food insecurity.
• Too few or too many nutrients can lead to health problems.
Copyright © The Teacher's Pet Life Sciences Grade 10 (Via Afrika) Page 4 of 31
Glossary
Term Definition
Import Give or take animal food.
Reagent Substance that identifies chemical reactions.
Immiscible Do not mix with water.
Luminous Let light through.
Helix Three-dimensional spiral shape.
Eutrophication Excess nutrients in water causes oxygen deficiency.
Enzyme Protein that accelerates chemical reactions.
Inorganic compounds
• Examples: water, oxygen, carbon dioxide.
• Water is important for: Transport, dissolving substances, temperature control.
• Mineral elements:
o For humans: Na, K, Ca, P, Fe, I.
o For plants: Macro - N, P, K, Ca, Mg, S | Micro - B, Cu, Cl, Mn, Mo, Zn.
Fertiliser and leaching
• Provide plants with nutrients.
• Leaching: when nutrients such as phosphate leach out.
• Result: Eutrophication - aquatic life is dying.
Organic compounds
• Carbohydrates: C, H, O - source of energy.
• Monosaccharides: glucose.
• Disaccharide: maltose.
• Polysaccharides: starch, glycogen.
• Tests:
o Starch: Positive - blue-black.
o Benedict/Fehling for glucose: Positive - red/orange.
Copyright © The Teacher's Pet Life Sciences Grade 10 (Via Afrika) Page 2 of 31
, Lipids (fats and oils)
• Consists of glycerol + fatty acids.
• Saturated (lard) vs. unsaturated (olive oil).
• Functions:
o Structure of cell membranes.
o Energy storage.
o Insulation and protection.
o Waterproofing in plants.
• Tests:
o Ether test: Positive - oil mark.
o Water test: Positive - does not mix with water.
Proteins
• C, H, O, N (+ sometimes S, Fe, P).
• Structures:
o Primary → order.
o Secondary → folding.
o Tertiary → 3D form.
o Quaternary → several chains.
• Tests:
o Millon: burgundy.
o Biuret: violet/purple.
• Factors affecting structure: temperature, pH, salt concentration.
Enzymes
• Specialized proteins.
• Function as biological catalysts.
• Optimum conditions: temperature and pH.
• Examples:
o Amilase - starch.
o Protease - proteins.
o Lipase - fats.
Nucleic acids
• DNA – stores genetic code.
• RNA - helps to make proteins.
Vitamins
• Essential for metabolism.
• Deficiency Diseases:
o A - night blindness.
o B - beriberi, pellagra.
o C - Scurvy.
o D - rickets.
o E - Nerve problems.
Copyright © The Teacher's Pet Life Sciences Grade 10 (Via Afrika) Page 3 of 31
, Balanced diet
• Include all the most important nutrients.
• Energy intake must correspond to energy consumption.
• 1g fat = 9 calories | 1g of protein or carbohydrate = 4 calories.
• ADH (Recommended Dietary Amount) shows how many nutrients a person needs daily.
Malnutrition
• Causes: poverty, environment, food insecurity.
• Too few or too many nutrients can lead to health problems.
Copyright © The Teacher's Pet Life Sciences Grade 10 (Via Afrika) Page 4 of 31
