1. Life sciences Grade 10 CAPS: structured, clear, practical Helping teachers unlock the power of NCS
KNOWLEDGE AREA: Life at the molecular, cellular and tissue level
Topic 1: Chemistry of life
Inorganic compounds

2. CAPS SPECIFIC AIMS 1. Knowing Life Sciences
2. Investigating Phenomena in Life
Sciences
3. Appreciating and Understanding the
History, Importance and Applications
of Life Sciences in Society

3. Specific Skills Access information Apply knowledge in new contexts
Select key ideas
Recall information
Describe knowledge of NS
Build a conceptual framework
Organise or reorganise knowledge
Write summaries
Develop flow charts and mind maps
Recognise patterns and trends
Apply knowledge in new contexts
Use knowledge in a new way
Analyse information/data
Critically evaluate scientific information
Recognise relationships between existing knowledge and new ideas
Identify assumptions
Categorise information

4. Chemistry of life
Summary layout
Minerals
Inorganic compounds

5. Elements Remember all compounds are made up of elements.
Elements are pure substances.
Elements bond to form compounds.
There are two types of compounds: organic and inorganic.
Inorganic compounds do not contain the element carbon 12, some examples of these compounds are water, minerals and gases like carbon dioxide.
Organic compounds contain the element carbon 12 and examples of these compounds are carbohydrates, proteins and lipids.

6. Mineral SALTS
Minerals are inorganic substances that are required by living organisms (plants and animals).
Minerals can be divided into two groups:
Micro-elements: required in small quantities
Macro-elements: required in large quantities

7. Maintains osmotic balance in plants Reduced plant growth
Functions of some minerals /MACRO ELEMENTS and their deficiency diseases.
Mineral
Function
Deficiency
Sodium
(Na)
Plants
Maintains osmotic balance in plants
Reduced plant growth
Animals
Has a role in the functioning of nerves and muscles
Regulates the secretion of HCl in the stomach
Muscle cramps
Potassium
(K)
Needed for: Photosynthesis
Protein synthesis, activation of plant enzymes
Regulation of the stomata
Lower drought resistance
Excessive water lose
disease
Regulation of : Blood pressure, nerve functions, muscle control, cellular respiration
Low oxygen levels
Muscular cramps
Lung failure

8. Used for the formation of the middle lamella of cell walls
Functions of some minerals/MACRO ELEMENTS and their deficiency diseases
Mineral
Function
Deficiency
Calcium
(Ca)
Plants
Used for the formation of the middle lamella of cell walls
Also maintains the permeability of cell walls
Poor plant growth
Growing parts of plant die
Animals
Required for bone and teeth formation.
Used in blood clotting
In children causes rickets
Phosphorous
(P)
needed for cell membrane formation and for the formation of nucleic acids
Used for the formation of ATP
Leaves fall off prematurely
Brown spots develop on leaves
Used for the formation of cell membranes, nucleic acids, ATP and bone and teeth
Rickets in children

9. Functions of some minerals/MICRO ELEMENTS and their deficiency diseases
Iron
(Fe)
Plant
Used in the formation of chlorophyll
Leaves become yellow due to the lack of chlorophyll. This is called chlorosis
Animals
Used for the formation of haemoglobin
anaemia
Iodine
(I)
Plants
Used in photosynthesis
Photosynthesis decreases causing a decrease in growth and death of the plant
Used in thyroxin formation
Causes enlargement of the thyroid gland. This disease is called goiter.

10. Functions of some minerals/MACRO ELEMENTS and their deficiency diseases
Nitrogen
(N)
Plants
Used by plants for the formation of amino acid, nucleic acids and chlorophyll
chlorosis
Animals
Required for protein synthesis and nucleic acids
Kwashiorkor in children
Magnesium
(Mg)
Used to make the central atom of chlorophyll molecule
Chlorosis
Used for bone and teeth formation and for nerve and muscle functioning
Muscle cramps

11. Something for you to do.
1. Explain what is meant by… 1.1 osmosis 1.2 protein synthesis 2. Describe … 2.1 chlorophyll 2.2 haemoglobin 2.3 amino acids 3. Explain why chlorosis occurs when there is an iron and nitrogen deficiency. 4. Name the gland that secretes thyroxin.

12. solution
1.1 osmosis is the movement of water from a region of high concentration to a region of low concentration across a differentially permeable membrane. 1.2 protein synthesis is the process during which proteins are made. 2.1 chlorophyll is a green pigment found in plants and is used to give plants the green colour and trap sunlight. 2.2 haemoglobin is a red pigment found in the red blood cell, its function is to give blood the red color and to transport gases. 2.3 amino acids are the building blocks of proteins. 3. Both iron and iodine is used to make chlorophyll, if these minerals are deficient then the plant cannot make enough chlorophyll and the leaves will lose their green colour. 4. Thyroid gland

13. The need for fertilizer in over used soil
In order for plants to grow they need nutrients.
These nutrients come from both the soil and air.
Nutrients enter the soil when dead plants and animals decay.
In order to achieve this richness of soil, decomposition should be encouraged.
Farmers can achieve this in two ways.
To leave the soil fallow
To plough back dead plants into the soil.

14. Fallow means: if the land is used constantly there is no time for the land to be left fallow or for natural nutrient recycling to occur.
Therefore the soil may become very infertile.
The farmer may use synthetic fertilizers to
replace the lost nutrients.
These fertilizers may contain phosphates and
nitrates.
When it rains these fertilizers may be washed out
into to the rivers.
The nutrient content of the river increases.
This increased nutrient content causes a rapid
growth of plant and algae in the water.
This is called eutrophication.

15. The increased plant growth especially the algae covers the surface of the water, preventing sunlight from reaching the plants lower down in the water.
These plants will die and the aquatic organisms that depend on these plants will also die.
The dead plant and animal matter begin to rot and attract bacteria to the water.
The increased bacteria uses more oxygen and this decreases the oxygen content of the water.
This results in more plants and animals dying.

16. water
Water can exist naturally in three states or phases: solid, liquid and gas.
In its solid state it exists as ice found in the polar ice caps, as a liquid it is called water and is found in the rivers, lakes and oceans and as a gas it is called water vapour and occurs in the atmosphere.
Importance of water:
1. The human body is made up of 60-75% water.
% of the cell is made up of water.
3. Water makes life on Earth possible.

17. STRUCTURE OF water:
One molecule of water is made up of two hydrogen atoms and one oxygen in the arrangement shown below.

18. Functions of water
1. It is used during digestion to break down large insoluble substances into smaller soluble substances. 2. It is a medium for all chemical reactions in the cell. 3. It is used to transport food along the alimentary canal and mineral salts in plants. 4. Dissolve the waste substance in the body to form urine and sweat.

19. Terminology Elements are pure substances.
Compounds are made up of two or more elements.
Inorganic compounds are compounds that do not contain the element carbon 12.
Organic compounds are compounds that contain the element carbon 12.
Minerals are inorganic substances that are required by living organisms.
Macro-elements are elements that are required in large quantities by living organisms.
Micro-elements are elements that are required in small quantities by living organisms.
Eutrophication is the rapid growth of the population of living organisms, usually aquatic plants , due to increased supply of nutrients.

20. Question 1
The mineral required for the prevention of muscle cramps is… A. K B. Na C. Ca D. Fe

21. Question 2
The mineral that is required for the formation of amino acids… A. K B. Na C. Ca D. N

22. Question 3
A deficiency of this mineral results in Goitre. A. K B. I C. Ca D. N

23. Question 4
Lack of iron results in a deficiency disease in plants called… A. Kwashiorkor B. Goitre C. Anaemia D. chlorosis

24. Question 5
A lack of this mineral results in lower drought resistance. A. K B. I C. Ca D. N

25. Question 6
The mineral that is used for formation of nucleic acids and the chlorophyll molecule is called… A. K B. I C. Ca D. N

26. Question 7
In order for a child to have good strong bones and teeth, his/her diet must be rich in the following minerals A. Ca and P B. N and I C. Fe and K D. Na and Mg

27. Question 8
To prevent chlorosis the soil must contain the following nutrients. A. Mg, I, Fe B. Na, P, K C. Fe, N, Mg D. I, P, K

28. Question 9
Phosphorous is used for the formation of… A. Central atom of the chlorophyll molecule. B. Nucleic acids C. Amino acids D. Thyroxin

29. Question 10
The central atom of the chlorophyll molecule is… A. Mg B. I C. Ca D. N

30. Question 11
The mineral that is the component of hemoglobin is… A. K B. I C. Ca D. Fe

31. Question 12
The mineral that is required for the middle lamella of cells and is used in the clotting of blood is… A. K B. I C. Ca D. N

32. Question 13
The pigment that is used for the transport of gases is called… A. Haemoglobin B. Chlorophyll C. Thyroxin D. None of the above

33. Question 14
The hormone that is secreted by the thyroid gland is called… A. Haemoglobin B. Chlorophyll C. Thyroxin D. None of the above

34. Question 15 Mineral that is found as the central atom of the
chlorophyll molecule and for functioning of nerves
and muscles.
A. K
B. I
C. Fe
D. Mg

35. Question 16
The inorganic substance that is involved in transport. A. water B. Haemoglobin C. Xylem D. thyroxin

36. Question 17
Minerals that are needed in small quantities are called… A. Micro-elements B. Macro-elements C. Mega-elements D. None of the above

37. Question 18
Mineral that are needed in large quantities by organisms… A. Micro-elements B. Macro-elements C. Mega-elements D. None of the above

38. Question 19
In order for a child to be free from rickets and kwashiorkor, his diet must be rich in… A. Ca and N B. K and P C. Ca and P D. N and K

39. Question 20
The element required for the formation of the pigment found in the red blood cell is… A. I B. K C. Fe D. P

40. solution B D A C

41. solution D C A B