SAMPLE. Natural Sciences Grade 9 Textbook and Workbook

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1 Natural Sciences Grade 9 Textbook and Workbook Santie du Plessis Pikkie du Toit Carlien Fanoy Natalie Janse van Rensburg Susan Keuris Patricia Lees-Rolfe Judy McDougall

2 Doc Scientia Posbus 7011 Ansfrere For any queries and feedback: Jacques Fanoy or Stephan Fanoy Office: Fax: ISBN: First edition December 2011 Revised edition December 2012 Second edition December 2013 Revised edition December 2014; 2015 Graphic design: Helene Jonck All rights reserved. No part of this publication may be reproduced in any form or by any means mechanical or electronic, including recordings or tape recordings and photocopying without the prior permission of the publisher.

3 Unit INDEX TERM 1 LIFE AND LIVING 13 Unit 1 CELLS AS THE BASIC UNITS 13 Page 1.1 Plant cells and animal cells Structure of cells Differences between plant cells and animal cells 15 Project Cells in tissues, organs and systems 15 Activity 1 15 Activity 2 16 Case study 19 Practical task 1 21 Exercise 1 21 Summary of Unit1 24 Mind maps of Unit 1 25 Unit 2 SYSTEMS IN THE HUMAN BODY Introduction 28 Practical task Digestive system Steps in digestion Types of digestion Organs Functions of the organs Nutrition and nutrients Balanced diet 36 Activity 3 37 Activity 4 37 Practical investigation Health issues 39 Activity 5 39 Exercise Muscular system Skeleton Muscles Tendons, ligaments and cartilage Diseases that affect the skeleton 49 Exercise Circulatory system Blood Anatomy Blood vessels Heart 54 Practical investigation 2 55 Practical task Health issues 57 Activity 6 58 Exercise Respiratory system 63

4 2.5.1 Anatomy Gaseous exchange and diffusion 65 Practical task Respiration 66 Activity Differences between inhalation and exhalation Health issues 67 Activity 8 67 Exercise Excretory system Anatomy Health issues 75 Exercise Nervous system and sensory organs Eye (sight) Ear (hearing) Tongue (taste) Skin (touch) Nose (smell) Impulses and the brain Thermoregulation Health issues The impact of drugs and alcohol on the brain 88 Exercise 7 88 Summary of Unit 2 92 Mind maps of Unit Unit 3 HUMAN REPRODUCTION AN PUBERTY Introduction Male reproductive system Female reproductive system Sexual intercourse Puberty Phases of reproduction Contraception Health issues 112 Activity Activity Exercise Summary of Unit Mind maps of Unit Glossary 120 Term test 123 TERM 2 MATTER AND MATERIALS 139 Unit 1 COMPOUNDS AND CHEMICAL REACTIONS Periodic Table General information Representation of elements Compounds 141 Practical task Exercise 9 144

5 1.3 Chemical reactions Chemical equations 148 Practical task Exercise Balancing 154 Exercise Summary of Unit Mind maps of Unit Unit 2 METALS AND NON-METALS Indicators ph scale 162 Practical investigation Practical investigation Reactions of metals with oxygen 164 Practical investigation Rust Prevention of rust Reactions of non-metals with oxygen 168 Practical investigation Exercise Summary of Unit Mind maps of Unit Unit 3 ACIDS AND BASES Acids Bases 178 Practical task Exercise Reactions of acids Acid with a metal 180 Practical investigation Practical investigation Exercise Acid with a metal oxide 184 Activity Acid with a metal hydroxide 186 Practical investigation Acid with a metal carbonate 188 Practical investigation Activity Exercise Summary of Unit Mind maps of Unit Glossary 196 Term test 197 TERM 3 ENERGY AND CHANGE 205 Unit 1 FORCES What is a force? 205 Practical task Practical task 9 206

6 Practical task Practical task Exercise Types of forces Gravitational force 210 Practical task Practical task Magnetic forces 213 Practical task Practical investigation Practical investigation Practical investigation Electrostatic forces 217 Practical investigation Exercise Summary of Unit Mind maps of Unit Unit 2 CELLS Source Chemical reactions 225 Practical investigation Connections Series 226 Practical investigation Parallel 227 Practical investigation Exercise Summary of Unit Unit 3 SERIES CIRCUITS AND PARALLEL CIRCUITS Conductors and resistors Conductors Resistors Factors that influence resistance 233 Practical investigation Electrical circuits Current Potential difference Resistance Series connection 237 Practical investigation Parallel connection 238 Practical investigation Exercise Summary of Unit Mind maps of Unit Unit 4 SAFETY WITH ELECTRICITY Wiring of households 245 Practical task Safety measures 247

7 4.2.1 Fuses and circuit breakers Lightning conductors 248 Activity Electrical energy theft 250 Activity Exercise Summary of Unit Mind maps of Unit Unit 5 NATIONAL ELECTRICITY GRID National network Coal power stations Alternative sources 257 Activity Exercise Summary of Unit Unit 6 COST OF ELECTRICAL POWER Cost calculation Saving electricity 269 Activity Exercise Summary of Unit Glossary 273 Term test 275 TERM 4 EARTH AND BEYOND 283 Activity Unit 1 LITHOSPHERE What is the lithosphere? Rock cycle Types of rock Igneous rock Sedimentary rock Metamorphic rock Steps of the rock cycle 290 Activity Minerals and ore 294 Exercise Extraction of minerals in South Africa Indigenous technology of extraction Modern day processes for extraction 298 Activity Environmental impact of mines 300 Activity Exercise Summary of Unit Mind maps of Unit Unit 2 ATMOSPHERE Composition Layers of the atmosphere Troposphere Stratosphere 310

8 2.2.3 Mesosphere Thermosphere The greenhouse effect 312 Activity Exercise Stars Birth Life Death 317 Activity Activity Summary of Unit Mind maps of Unit Glossary 324 Term test 325 Information sheet 331 Work cited 332

9 Cells as the basic units UNIT 1 Cells as the basic units of life TERM 1: LIFE AND LIVING Life and living Systems in the human body CELLS AS THE BASIC UNITS A cell is the basic structural and functional unit of all living organisms. Cells are microscopic and cannot be observed with the naked eye. Microscopes are used to observe cells. 1.1 Plant cells and animal cells Human reproduction and puberty Plant cells and animal cells Structure of cells Differences between plant cells and animal cells Cells in tissues, organs and systems Cells 1. Membrane 2. Cytoplasm 3. Nucleus 4. Organelles 1. Membrane: The membrane surrounds the cell. It allows certain substances to move in and out of the cell. The membrane is living, thin and pliable. 2. Cytoplasm: The cytoplasm is a liquid in which the chemical processes (metabolism) can take place in the cell. The largest part of the cell consists of cytoplasm, which is a jelly-like substance. Doc Scientia NATURAL SCIENCES textbook and workbook - Grade 9 13

10 life and living 3. Nucleus (core): The nucleus is surrounded by the nucleus membrane. The nucleus contains the DNA of the cell. DNA carries the genetic code with which the cell reproduces. DNA contains hereditary characteristics which determine things like the colour of your eyes. Each persoon's DNA is unique. Due to the variation, differences occur in species. The nucleus controls the life functions and processes of the cell. 4. Organelles: Organelles include the mitochondria and vacuole. The mitochondria is responsible for respiration in cells, and release energy. 1.2 Structure of cells The structure of the plant cell is as follows: cell wall cell membrane cytoplasm mitochondria The structure of the animal cell is as follows: vacuole nuclear membrane nucleoplasm tonoplast cell sap chloroplast nuclear membrane vacuole nucleus mitochondria nucleoplasm cell membrane cytoplasm 14 NATURAL SCIENCES textbook and workbook - Grade 9 Doc Scientia } } } nucleus

11 life and living 1.3 Differences between plant cells and animal cells Plant cell 1. Cell wall Present It consists of non-living cellulose which is rigid. The cell wall gives the shape of the cell and provides protection. 2. Shape of Inflexible and firm cell 3. Vacuole Large vacuoles The vacuole contributes to the shape of the cell. The vacuole is also used as storage for nutrients, water and even waste products. 4. Chloroplast Chloroplasts are only found in green plants. Chloroplasts contain chlorophyll which allows the plant to photosynthesise. Photosynthesis is the process whereby green plants produce food (glucose and starch) in the presence of sunlight. Project Date: Animal cell Not present No fixed form Small vacuoles Vacuoles in animal cells are temporary or not present. Animal cells do not contain chloroplasts. Build a 3D plant cell that meets the following requirements: It must be approximately the size of an A4 paper. Be as creative as possible. Use different kinds and colours of sweets, play dough, different colours of cardboard or anything from nature to represent the different parts of the cell. 1.4 Cells in tissues, organs and systems Cells are found in a variety of sizes and shapes. Microscopic organisms, like bacteria, consist of only one cell and are studied under a microscope. Macroscopic organisms, like people, consist of a large number of cells. Activity 1 Date: Do research on the history and discovery of light microscopes and electron microscopes. Search for pictures. Make a poster. Do a presentation in class. Doc Scientia NATURAL SCIENCES textbook and workbook - Grade 9 15

12 Activity 2 life and living Study the named sketch of the basic light microscope. Date: Complete the table below about the function of each of the parts that are listed. Part coarse focus knob fine focus knob arm adjustable inclination base Function eye piece Eye piece Tube Coarse focus knob Fine focus knob 16 NATURAL SCIENCES textbook and workbook - Grade 9 Doc Scientia tube revolving nosepiece small objective large objective clamps table/stage diaphragm mirror/light source

13 Arm Part Revolving nosepiece Objectives Table/stage Clamps Diaphragm Light source Base Function There are cells that are specialised. This means that these cells are adapted to perform specific functions. Here are a few examples of specialised cells: Stem cells Muscle cells Cell life and living Function These cells have the ability to: divide and develop into different types of cells. Example: Stem cells can develop into nerve cells, muscle cells and bone cells. These cells contract and relax to enable movement. Doc Scientia NATURAL SCIENCES textbook and workbook - Grade 9 17

14 Nerve cells Red blood cells Cell life and living Cell A group of cells that function together for the same purpose forms tissue. A group of systems that function together forms an organism. Function Nerve cells transfer electrical impulses in the nerves and the spinal cord. The red blood cells transport oxygen throughout the body. A group of tissues that function together forms an organ. A group of organs that function together forms a system. 18 NATURAL SCIENCES textbook and workbook - Grade 9 Doc Scientia

15 Case study Date: life and living Stem cells and stem cell research Stem cell research has been hailed as a miracle cure by the medical fraternity, because there is the possibility of solutions for incurable diseases, e.g. cancer, Alzheimer s and Parkinson s. Researchers believe that stem cells can be used to regenerate damaged and diseased organs. On the other hand, stem cell research has been highly controversial, due to the ethical issues concerned with the culture and use of stem cells derived from human embryos. But what is a stem cell? Stem cells are unspecialised cells that have two defining properties: the ability to differentiate into any other type of cell, and the ability to self-regenerate (they can divide and produce more stem cells). Stem cell research is research done on embryonic stem cells. It focuses on medical prospects such as healing diseases that are currently incurable. There are ethical questions that come to light when one talks about stem cell research. 1. The research destroys human embryos. Every living person started life as an embryo. The debate is whether the destruction of embryos is murder or not. 2. Stem cell research could lead to unethical behaviour, for example embryo farms, cloned babies and the use of foetuses for organ donation. The counter-arguments are: 1. Embryos cannot be compared to living, complete organisms. Therefore the use of embryo stem cells cannot be considered murder. 2. If it is unethical to use embryos for research, then it is just as unethical to use embryos for in-vitro fertilisation. Most fertility clinics prepare more embryos than they need. The excess embryos are frozen or destroyed. If it is therefore immoral to use embryos to cure devastating diseases, it is also immoral to use embryos to overcome infertility. Questions: 1. What is a stem cell? 2. What is an embryo? _ Doc Scientia NATURAL SCIENCES textbook and workbook - Grade 9 19

16 life and living 3. What is stem cell research? 4. Why was stem cell research hailed as a miracle cure by the medical fraternity? 5. Which two ethical questions caused controversy in the debate about stem cell research? State your answer in just one sentence. 6. Give your own opinion of stem cell research. Do you agree with it or not? Do further research about stem cell research to support your answer for Question 6. Discuss your findings in class. Take into consideration that stem cells can also be obtained from blood from the umbilical cord after birth. How does this statement influence your opinion? 20 NATURAL SCIENCES textbook and workbook - Grade 9 Doc Scientia

17 Practical task 1 Exercise 1 1. Name three specialised cells as well as the function of each. life and living Date: 2. Explain the following briefly: Tissue Organs Systems Organism 3. Name the four parts found in all cells. 4. What is the function of the cell nucleus? 5. Draw a simple sketch to represent an animal cell. Remember to give your sketch a heading and labels. Date: Prepare plant cells and animal cells (e.g. cells from an onion and mucous) and study it under a microscope. Draw and name the cells that are studied. Doc Scientia NATURAL SCIENCES textbook and workbook - Grade 9 21

18 life and living 6 Study the sketches in the following table. Identify them as cells, tissue, organs, systems or organisms NATURAL SCIENCES textbook and workbook - Grade 9 Doc Scientia

19 7. Draw a simple sketch to represent a plant cell. Remember to give your sketch a heading and labels. 8 What is the function of: 8.1 the cell wall? life and living 8.2 the chloroplasts? 8.3 the vacuole? Notes Doc Scientia NATURAL SCIENCES textbook and workbook - Grade 9 23

20 life and living Summary 1. Membrane 2. Cytoplasm 3. Nucleus 4. Organelles Plant cell 1. Cell wall Present It consists of non-living cellulose which is rigid. The cell wall gives the shape of the cell and provides protection. 2. Shape of cell Inflexible and firm 3. Vacuole Large vacuoles The vacuole contributes to the shape of the cell. The vacuole is also used as storage for nutrients, water and even waste products. 4. Chloroplast Chloroplasts are only found in green plants. Chloroplasts contain chlorophyll which allows the plant to photosynthesise. Photosynthesis is the process whereby green plants produce food (glucose and starch) in the presence of sunlight. Cell Stem cells Muscle cells Nerve cells Red blood cells Cell Cells Function Not present Animal cell No fixed form Small vacuoles Vacuoles in animal cells are temporary or not present. Animal cells do not contain chloroplasts. These cells have the ability to divide and develop into different types of cells. These cells contract and relax to enable movement. Nerve cells transfer electrical impulses in the nerves and the spinal cord. The red blood cells transport oxygen throughout the body. A group of cells that function together for the same purpose forms tissue. A group of systems that function together forms an organism. A group of tissues that function together forms an organ. A group of organs that function together forms a system. 24 NATURAL SCIENCES textbook and workbook - Grade 9 Doc Scientia

21 All cells contain Plant cell A group of cells A group of systems 1. Shape Rigid Flexible 2. Cell wall 3. Vacuole containing cell sap 4. Chloroplast CELLS AMPLE Animal cell A group of tissue A group of organs