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2 Other books oks in this series es Help us to deliver a better product with each print by sending your suggestions to: improve@amaniyah.co.za First edition 2019 Warning!! All rights reserved according to the South African copyright act. No part of this book may be reproduced by photocopying or any other method without written permission of the publisher and writer. Any person who exercises any unauthorized act in relation to this publication may be subject to criminal prosecution and civil claims against damage. Compiled by J.M. Grobler Published by: Tel: Cell: (no sms Vodacom)/ (no sms MTN) admin@amaniyah.co.za/ ISBN

3 TABLE OF CONTENTS PAPER STRAND 1 DIVERSITY, CHANGE AND CONTINUITY 2 Protista Bacteria Fungi The pteridophytes The gymnosperm Angiosperms Biodiversity in the animal kingdom The phylum : the sponges The phylum platyhelminthes The phylum annelida The phylum arthropoda The phylum chordata STRAND 3 ENVIRONMENTAL STUDIES Human impact on the environment The effect of population growth on the environment Water Food security The loss of biodiversity Indigenous knowledge The processing of solid waste

4 STRAND 2 PAPER 1 LIFE PROCESSES IN PLANTS AND ANIMALS Energy transformations to sustain life 104 Nutrition in mammals Release of energy: cellular respiration STRAND 2 LIFE PROCESSES IN PLANTS AND ANIMALS (continue) Gas exchange in organisms 152 The excretory system Population ecology Determining population size and population density Symbiosis Social change over time: ecological succession

5 GRAPHS THAT YOU ALREADY MASTERED A. The line graph 1. Always provide your graph with a heading, which include the x and y- axis s information. 2. The axes must have the correct scale format (e.g. 2,4,6,8 Or 3,6,9,12 etc.) and must start with zero value. 3. Choose the correct scale, and keep equal scale distribution throughout. 4. The x-axis represents the independent variable day, years etc. 5. The y-axis represents the dependent variable because the values are determined by external factors (found on the x-axis). 6. The headings of the axes with their units must always be indicated. The points on the graph must be clearly indicated according to the x- and y-values. 7. A line graph begins at zero only if there is a true value at zero. For example Plot the reaction rate of an enzyme versus time, making use of the following results. X-axis (Temperature in C) Y-as (Reaction rate in mg/min) 2,0 3,5 4,5 5,5 5,5 1,2 Solution Reaction rate of an enzyme versus time 6,0 Reaction rate of an enzyme (mg/min) 5,0 4,0 3,0 2,0 1,0 0, Temperature ( C) B. Pie charts 1. The full circle represents 100% of All the segments together will thus be 100% of For example Represent 10%, 20% and 30% using a pie chart Solution The degrees of the circle is calculated as follows: 10 10% = x 360 = measure 36 from % = x 360 = measure = 108 from 0 35% 20% 10% % = x 360 = 126 measure = 234 from Measure using your protractor from 0 to start 234

6 C. Histograms 1. Groups of data are illustrated next to each other to compare them. 2. A series of data is thus displayed next to each other like time and age. 3. The columns touch and are equally wide. 4. The axes as well as the units of the axes must be approached the same as the line graph. For example Display the population amount versus age groups using a histogram. Age group Population (in millions) Solution 3,0 2,75 2,5 2,25 Population (in millions) 2,0 1,75 1,5 1,25 1,0 0,75 0,5 0,25 0, Age group D. Column graph / bar graph. 1. The column graph almost looks the same as a histogram, but there are spaces in between the columns. 2. Each column / bar basically represents something else and no sequence is formed. 3. Each column must have the same width. For example This column graph represents the preference of pets with male and female students Amount of students in hundreds Favourite pet with men Favourite pet with ladies 0 Dogs Cats Fish Type of pet

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8 PAPER 2 DIVERSITY, CHANGE AND CONTINUITY 1

9 STRAND 1 DIVERSITY, CHANGE AND CONTINUITY BIODIVERSITY AND CLASSIFICATION OF MICROORGANISMS Microorganisms 1. Microorganisms are very small organisms that can t be seen with the naked eye. 2. Microorganisms contribute toward the biodiversity of ecosystems, since millions of them are present and they form important links in food chains. 3. Microorganisms play a role in - disease e.g. tuberculosis, HIV/Aids, cholera, malaria etc. - food manufacturing e.g. yeast used to make wine, beer and cheese, bake bread, etc. - food decay through fungi and bacteria - sewage treatment through bacteria. 4. They include the following groups: - viruses that range between 0,01 um and 0,1 um ( 1 um = 0,001 mm) - bacteria that range between 0,1 um and 5 um - protista - unicellular organisms like Amoeba as well as those that cause disease e.g. malaria - fungi - like bread mould and mushrooms. Viruses Bacteria Protista Fungi VIRUSES 1. Viruses can literally be seen as inert or dormant. They suddenly come to life as soon as they enter cells of other organisms (plants and animals). 2. They are all, without exception, parasites on other organisms where they cause disease. 3. In 1918, 20 million people died during the big flu pandemic that was responsible for more deaths than World War I! 4. Viruses only have one vital function, and that is REPRODUCTION! - Therefore all other metabolic activities are absent. 5. Viruses are transported passively through air, water, touch and bodily fluids. Thousands of people died during the great flu pandemic Nurses in

10 B. The structure of viruses 1. They are exceptionally small and are only visible under very high magnification with an electron microscope. 2. They are acellular since they don t have a true nucleus, ribosomes or mitochondria. 3. The body consists of: - a capsid / protein shell made up of capsomeres - that encloses the nucleic acid. 4. The nucleic acid is: - RNA in viruses that live on plant cells and - DNA / RNA in viruses that live on animal cells. 5. Their shape can range from rod-shaped to spherical (round). The flu virus The tobacco mosaic virus Capsomeres form the capsid Lipid sheath RNA Capsomere Nucleic acid Membrane sheath Structure of a bacteriophage, a virus that attacks bacteria Under the electron microscope capsid nucleic acid tail fibers tail with contractile tail sheath 3

11 C. Reproduction / Replication of viruses 1. Viruses can only reproduce inside living plant or animal cells and are therefore parasites and - absolutely specific since they specialise on specific hosts. 2. The virus attaches itself to the cell and injects its nucleic acid into the cell. 3. The protein shell stays behind outside the cell. 4. Inside the cell the DNA / RNA takes over the host cell s DNA / RNA. 5. It therefore changes the chromosomes of the cell, which can be seen as a mutation! 6. The virus-dna now controls the cell and the cell is used to produce new viruses. 8. As soon as the cell is depleted and full of new viruses, it bursts open and the new viruses are released. 9. The newly formed viruses attack other cells in the organisms body. Replication of bacteriophage viruses Virus attaches to host cell New viruses released Bacterium DNA is forced inside - and controls the host s DNA Host cell filled with new viruses The host cell builds new viruses Replication of bacteriophage under electron microscope DNA is forced into the cell Bacterium cell 4

12 D. Biological importance of viruses Viruses cause disease in plants, animals and humans. I. In plants 1. Abnormalities in plants cause enormous economical losses. 2. The tobacco mosaic virus on tobacco leaves causes CHLOROSIS in the leaves. - The leaves turn yellow because no chlorophyll can be formed. - These tobacco leaves are useless to the farmer. II. In animals and humans Viruses are spread through: 1. Food and drinking water. 2. During contact when someone coughs or sneezes and through sexual contact. 3. Vectors (carriers) like mosquitoes, ticks, fleas and aphids can easily transfer viruses through their saliva. - The HIV-virus is yet not transmitted by mosquitoes! (Thank goodness!). DISEASES CAUSED BY VIRUSES DISEASE CAUSES AND SYMPTOMS TREATMENT 1. Rabies caused by the Rhabdo virus. 1. The animal is infected through the bite from another rabid animal. 2. The saliva of the sick animal is filled with viruses. 3. The virus attacks the central nervous system and then the other organs. 4. The infected animal appears tame with foam around its mouth and it develops a fear of water, that is called hydrophobia. 5. Hallucinations and confusion occur. 6. The animal dies a terrible death. 1. Louis Pasteur developed a vaccine against rabies. 2. Pets are inoculated every six months. 3. During immunization impaired viruses are injected so that the body can build up antibodies against the disease. 4. In future it will protect the person against the disease. 2. Aids caused by the HIV-virus. It is a spherical retrovirus. 1. Aids stands for acquired immune deficiency syndrome. 2. The virus is transmitted - from a mother to her baby, - through contact with blood - and sexual intercourse. 3. The virus attacks the immune system by decreasing the T-cells that protect the body against infections. 4. The person dies from opportunistic diseases like tuberculosis and pneumonia. 1. Anti-retroviral drugs. 2. No treatment is possible in the advanced stage. 3. Here prevention is the only solution! (See later). 3. Flu and cold 1. Is contracted through direct contact with viruses in the air, contact with infected hands after sneezing, nose blowing, coughing, etc. 1. Drink lots of water and rest. 2. Only the symptoms are treated. 3. Immunisation is available.. 4. German measles / Rubella 1. Causes abnormal foetuses during the first four months of pregnancy, which justifies an abortion 1. Immunisation is available. 2. Girls must be infected to build natural immunity against the virus. 5

13 EFFECT AND MANAGEMENT OF AIDS IN SOUTH AFRICA A. The four stages after infection with the HIV-virus 1. Primary HIV-infection - The virus migrates to the lymph nodes where many new HIV-viruses are produced. 2. Seroconversion - The production of antibodies against the HIV-virus occurs. - Flu-like symptoms, rash and swollen lymph nodes are present. - Breaking out in sweat during the night, which is referred to as night-sweat. - The person tests positive for the HIV-antibodies. - The person is now HIV-positive without any symptoms. - This stage can last between a few weeks and 13 years! 3. Opportunistic infections now make their appearance - Other Aids-related diseases like viral, bacterial and fungal infections now occur. - Weight loss occurs. - The T-cells decrease and a lowered T-cell count is present. 4. Aids-related diseases worsen. - Organs are attacked and weight loss becomes severe. - Diarrhoea, fever and fatigue are present. - The person dies of opportunistic diseases such as pneumonia, tuberculosis etc. B. Aids statistics / numbers WHY ARE AIDS STATISTICS OFTEN INACCURATE? 1. Many cases aren t reported, only certain people are tested. 2. Many people aren t aware that they are HIV-positive and are in the window period. 3. Many people that were tested could have emigrated or died. 4. Mistakes are made during the compilation of statistics. 5. Statistics are often outdated and therefore inaccurate. C. Factors that decrease the number of Aids cases 1. More condoms are freely available. 2. People are more faithful to their sexual partners. 3. Abstinence (no sex) is becoming fashion. 4. More people are dying of Aids and are no longer part of the statistics 5. Fewer mothers transfer the virus to their children. 6. Successful training programmes and awareness of the spread of HIV are increasing. D. Factors that increase the number of Aids cases 1. Increase in promiscuity - people become sexually active at a very young age. 2. Unfaithfulness - more than one sexual partner. 3. Being uninformed - people don t believe that the HIV-virus can kill them 4. People in rural areas - People don t have access to condoms and clinics. 5. Training programmes and creating awareness of the spread of HIV are insufficient 6

14 E. Should the government test all people and make their HIV-status known? I. Benefits 1. Making a person s HIV-status known enables their sexual partners to protect themselves. 2. Planning by the government and other institutions for medical care can be done. Budgets can be planned ahead. 3. Infected persons can be helped to prevent further infections. 4. Couples will be more faithful to each other. 5. More accurate statistics will be available. II. Disadvantages 1. An individual s rights to his or her own privacy are violated. 2. Discrimination and rejection by friends and colleagues can occur. 3. Suicide can increase among Hiv-positive people. 4. The costs of testing the entire population are very high. 5. Information can be abused and employers can discriminate against HIVpositive employees. IMMUNITY AGAINST VIRUSES 1. If a person comes in contact with the virus, the person builds up immunity against the virus by producing antibodies that will recognise and destroy the virus. This is called active immunity. 2. That is why babies can be vaccinated against diseases. 3. The vaccine contains weakened strain/dead viruses. - The baby is literally infected with the disease so that it can form antibodies against the particular virus. 4. Babies also receive antibodies from their mothers through breast milk - This is called passive immunity. 5. Plants are specially cultivated to make them resistant or immune against certain viruses. ACTIVITY 1 : VIRUSES 1. Why is it illegal to take meat like biltong or fresh fruit and vegetables through customs at the airport? 2. Do you think it is possible that Aids can be transmitted by mosquitoes in the future? 3. Can a virus which is pathogenic on plants, also cause disease in humans? 4. Why do you have to wash your hands after blowing your nose? 7

15 5. Where does the saying Bless you! when someone sneezes come from? (Ask Uncle Google!) 6. How are viruses transported inside a) animals b) plants? 7. What is meant by mutations? Can it be an explanation for why you get the flu every year? 8. Study the following information regarding Aids as provided by the South African Department of Health and answer the questions that follow. Table 1 : The percentage of HIV-positive women that visited prenatal clinics in South Africa. Age <20 16,5 16,1 15,4 14,8 15,8 16, ,6 29,1 28,4 29,1 30,3 30, ,4 30,6 31,4 34,5 35,4 38, ,7 23,3 25,6 29,5 30,9 34, ,2 15,8 19,3 19,8 23,4 24, ,5 23,1 26,2 26,4 25,8 17,5 Table 2 : The number of HIV-positive people tested at clinics in South Africa. Group Women 2,5 million 2,95 million 3,1 million 3,3 million Men 2,2 million 2,3 million 2,4 million 2,8 million Babies Total 4,7 million 5,3 million 5,6 million 6,29 million Graph 1. The percentage of HIV-positive people tested at clinics in South Africa. Percentage of the population infected Age (Years) 8

16 8.1 In which age group is the highest percentage of HIV-positive people? GROUP ANSWER POSSIBLE EXPLANATION Age Gender 8.2 Which group has the lowest percentage of HIV-positive people? GROUP ANSWER POSSIBLE EXPLANATION Age Gender 8.3 Why does the occurrence of Aids decrease in the higher age groups? 8.4 What do you think is the best solution to combat Aids in South Africa? 8.5 Discuss the statement: Condoms should be freely available in school bathrooms. 8.6 How is Aids transmitted to newborn babies? 9

17 8.7 Do you think that anti-retrovirals should be made freely available to all? Give a reason for your answer. 8.8 In 2004, 60 million people in the world were HIV-positive. What percentage of this number was in South Africa? Show all your calculations! 8.9 The following slogan is used on bill boards on the side of the road. If you love me, protect me! Use a condom! Think of your own slogan to make people aware of the danger of Aids. Examples of educational campaigns taking place: 8.10 Explain how a baby can become immune to a certain virus by referring to passive and active immunity The trend shown by the above tables and the graph is that the number of HIV-positive people is increasing. Can you give a possible explanation for this? 10

18 PROTISTA 1. The protista contain organisms that can be characterised by their eukaryotic composition, - seeing that they contain a true nucleus and cell organelles inside the cell membrane 2. The simplest example is the Amoeba that can be found in the muddy sediments of clean freshwater ponds. THE AMOEBA Pseudopodium Cell membrane Contractile vacuole Endoplasm Nucleus Ectoplasm 3. Other examples are green algae like Spirogyra and Euglena, which can photosynthesise and are found in freshwater pools. Euglena have flagella that they use to swim! (A plant-like animal or an animal-like plant??) Spirogyra Euglena 4. Protista can cause diseases such as: - Plasmodium sp. that is transmitted by the Anopheles mosquito and causes Malaria. - Trypanosoma sp. that is transmitted by the Tsetse fly and causes sleeping sickness 5. The mosquito and the Tsetse fly act as vectors (they transmit the parasite) 6. Sleeping sickness is characterised by a high fever, anaemia, drowsiness and eventually death. Trypanosoma parasite in the blood 11

19 MALARIA 1. Malaria is a tropical disease that occurs in 90 countries, - and is caused by a group of unicellular parasites, protista, - that feed on the red blood cells of reptiles and mammals. 2. There are four species of malaria that parasitize on humans, namely - Plasmodium falciparum, P. ovale, P. vivax and P. malariae. 3. P. falciparum is the most dangerous and the most common in Africa 4. Plasmodium is transmitted by the female Anopheles mosquito - which acts as the vector. 5. Malaria is the cause of more than a million deaths worldwide, of which 90% are in Africa. 6. Malaria is responsible for one out of every four deaths among children 7. The chemical substance Chloroquine is the safest to use against Malaria, - but has already become less effective against the parasite. THE LIFE CYCLE OF PLASMODIUM Two stages are found in humans, namely in the liver and in the erythrocytes / red blood cells. A. The liver stage 1. The human is infected by sporocysts that - are present in the saliva of the female Anopheles mosquito. 2. The sporozoites migrate to the human liver. 3. Each sporozoites produces up to merozoites through mitosis, - that are released into the bloodstream. B. The blood stage / erythrocytic phase 4. Red blood cells are attacked by the merozoites 5. The destruction of red blood cells causes - anaemia, which results in the person feeling tired and listless. 6. Erythrocytes that burst open and release merozoites - cause a high fever of up to 40 C in the infected person as well as flu-like symptoms. 7. Malaria can normally only be detected in the blood during this stage. 8. These merozoites can in turn attack other liver and red blood cells. 9. The kidneys, liver and spleen are overloaded by toxins, which can lead to death. 10. Some merozoites develop into male and female gametocytes. 11. Gametocytes are ingested with the blood by the Anopheles mosquito when it bites an infected person. 12. The gametocytes form gametes inside the mosquito s stomach. 13. The male gamete fertilise the female gamete and form zygotes that infiltrate the gut wall. 14. The zygote undergoes meiosis and forms an oocyst inside the gut wall of the mosquito. 15. The oocyst forms many sporoziotes that migrate to the salivary glands of the mosquito. 16. And so the mosquito can, in turn, infect the next person. 17. The parasite doesn t affect the mosquito in any way. 18. Up to 2 million P. falciparum parasites can be present in a person and can destroy 40% of the erythrocytes before death sets in. male gamet The Anopheles mosquito Merozoites are released from the red blood cells The male gamete looks like a small octopus! 12

20 THE LIFE CYCLE OF PLASMODIUM (MALARIA PARASITE) A. In humans Mosquito 1 - Cycle starts here Mosquito 2 is now infected Sporozoites Liver Stage 1 Mosquito 1 - Infects human Liver Merozoites invade erythrocytes 2 Blood Stage Mosquito 2 - Infected now Gametocytes B. In the mosquito Sporozoites Fertilisation Oocyst Mid-gut Salivary glands Oocyst Human Human is infected 13

21 ACTIVITY 2 : MALARIA Study the following information regarding malaria and answer the questions that follow. 1. Malaria is controlled in the following ways: - using drugs like chloroquine to prevent malaria - spraying bodies of water where mosquitoes breed with pesticides - using mosquito nets over beds - using pesticides in houses - draining / drying up of bodies of water where mosquitoes breed - introducing fish that eat the larvae of the mosquitoes - developing a natural immunity in humans that are infected frequently 2. The graph of the appearance of malaria in an informal settlement in South Africa from 1989 to 2004, as provided by the South African Medical Research Council (SAMRC): Which method of control is the most harmful to the environment? Explain your answer 2. Which method of control is the most environmentally friendly? Explain your answer 3. Why is infection in women so much more common than in men? 4. What could possibly have caused the enormous outbreak between 1998 and 2000? Keep in mind where mosquitoes breed! 5. Do you think that someone who is HIV-positive can be more susceptible to malaria? Give reasons for your answer 6. Would somebody that has Aids be more likely to die from malaria than somebody that doesn t have Aids? Give reasons for your answer 14