National Curriculum - drdwyer.com.au - Overview Chapter 1 Science Inquiry Skills 1 Chapter 2 Cells 27 Chapter 3 Multi-cellular Organisms 59 Chapter 4 Reproduction 87

National Curriculum Dr Terry Dwyer

8

Dr Terry DwyerCertT, BAppSc, BEd, GDipEd, MEd(Hons), PhDHead of Learning Area

ScienceNational Curriculum

www.drdwyer.com.au

8

The cover: Two of the most common elements on Earth are oxygen in the air, the water (H2O), and the sand (SiO2), and silicon in the sand (SiO2).

“Nothing in life is to be feared, it is only to be understood. Now is the time to understand more, so that we may fear less.” - Marie Curie.

“In today’s world, economic access and full citizenship depend crucially on math and science literacy.” - Robert P. Moses.

Dr Dwyer Pty LtdABN 2710559392210 Moss CourtStanthorpe 4380www.drdwyer.com.au

Copyright © Dr Dwyer Pty LtdFirst Published 2014

Reproduction and communication for educational purposesThe Australian Copyright Act 1968 allows a maximum of one chapter or 10% of the pages of this work, whichever is the greater, to be reproduced and/or communicated by any educational institution for its educational purposes provided that the educational institution (or the body that administers it) has given a remuneration notice to Copyright Agency Limited under the Australian Copyright Act 1968.For details of the Copyright Agency Limited licence for educational institutions contact: [email protected]

Reproduction and communication for other purposesApart from fair dealing for the purposes of study, research, criticism or review, or as permitted under Part VB of the Australian Copyright Act 1968, no part of this book may be reproduced by any process without permission.

National Library of AustraliaCataloguing-in-Publication entryAuthor: Dwyer, T. (Terry), Title: Science year 8 : national curriculum / Dr Terry Dwyer

ISBN: 9780646912004 (paperback)

Notes: Includes index.Target Audience: For secondary school year age.

Subjects: Science--Australia--Textbooks. Science--Australia--Problems, exercises etc.

Dewey Number: 500

Published in Australia by Dr Dwyer Pty LtdPrinted in Malaysia

All due care should be taken when performing activities. No activity should be performed without direct supervision by a qualified supervisor. Neither the publisher nor the author can accept responsibility for any injury that may be sustained when performing activities described in this textbook.

Contents - Overview

Chapter 1 Science Inquiry Skills 1

Chapter 2 Cells 27

Chapter 3 Multi-cellular Organisms 59

Chapter 4 Reproduction 87

Chapter 5 Matter 103

Chapter 6 Elements & Compounds 125

Chapter 7 Chemical Reactions 145

Chapter 8 Rocks 169

Chapter 9 Minerals 191

Chapter 10 Energy 207

Glossary 237

Index 245

Chapter 3 Multi-cellular organisms 59

Multi-cellular organisms contain systems of organs that carry out specialised functions that enable them to survive and reproduce (ACSSU150).

� identify the organs and overall function of a system of a multicellular organism in supporting the life processes.

� describe the structure of each organ in a system and relating its function to the overall function of the system.

� examine the specialised cells and tissues involved in structure and function of particular organs.

� compare similar systems in different organisms such as digestive systems in herbivores and carnivores, respiratory systems in fish and mammals.

Make a stethoscope to listen to the heart.

Listen to a heartbeat - can you hear a 'lub' then 'dub' with quietness between the 'lub' and 'dub'?

A TaskAorta

Left atrium

Left ventricle

Pulmonary artery

Pulmonary vein

Right atrium

Right ventricle

8000 BC Evidence of use of the popular heart symbol.

2000 BC Egyptians believe that the heart is the basis of life and immortality.

300 BC Greeks believe that the heart is the centre of the soul and provides heat to the body.

200 BC Galen describes valves, venticles, veins, and arteries unaware of circulation of the blood.

1628 William Harvey details the circulation of blood driven by the pumping of the heart.

1967 Christiaan Barnard performs first heart transplant.

1982 Willem DeVries implants a permanent artificial heart.

Transplanted heart (Kaleda, Wikimedia Commons).

3.1 Cells to Systems60

Animalia Plantae Fungi Protista MoneraCannot make their own food and rely on other organisms for sustenance.

Use chlorophyll and sunlight to make their own food.

Cannot make their own food. Reproduce by spores.

Most use chlorophyll and sunlight to make their own food. Mostly single-celled organisms with a nucleus.

Single cell organisms without a nucleus.

Mammals, birds, reptiles, amphibians, fish, jellyfish, insects, spiders, crabs, snails, earthworms.

Flowering plants, ferns, pines, mosses.

Mushrooms, yeasts, moulds, mildew.

Algae, seaweed, amoebae, paramecium.

Bacteria and blue-green algae.

Cell wall, nucleus with membrane, no chloroplasts, mostly multicellular.

Cell wall, nucleus with no membrane, mostly no chloroplasts, unicellular.

Cell wallDNAnucleus

Cell membrane

flagellum

No cell wall, nucleus with membrane, no chloroplasts, multicellular.

Cell membrane

Nucleus

Vacuole

Cell wall, nucleus with membrane, chloroplasts, mostly multicellular.

Cell wall

Cell membrane

Chloroplast

Nucleus

Vacuole

Cell membraneCell wall

Nucleus

Mostly no cell wall, nucleus with membrane, mostly no chloroplasts, mostly unicellular.

Cell membrane

Flagellum

Nucleus

Chapter 10 Energy 61 Chapter 3 Multi-cellular organisms 61

The cell is the basic unit of life. All organisms (living things) are made up of cells. Cells have many different shapes. Most cells are microscopic.

Living things are made of cells. Many of the chemical reactions that keep living things alive happen in the cell.

The Cell

1 Draw and label a typical plant cell.

2 Draw and label a typical animal cell.

3 Describe the function of each of the following organelles found in plant cells:

a) cell membrane. b) nucleus. c) mitochondria. d) cytoplasm.

4 Why would you expect to find mitochondria in plant cells as well as animal cells?

5 Why would you expect more mitochondria in a muscle cell than in a pancreas cell?

6 Write the following symbolic equation for respiration in words:

O2 + C6H12O6 → energy + H2O + CO2

Exercise

A cell membrane• a thin covering holding and

protecting the cell.• lets oxygen and dissolved

food into the cell.• lets carbon dioxide and

wastes out of the cell.

Cytoplasm• jelly-like substance making

up most of the cell.• where the important

reactions take place.

A nucleus• the dark spot in the cell.• has DNA which controls the

action of the cell.

Most cells contain

Mitochondria• tiny powerhouses in the cell.• converts glucose into energy

(respiration). O2 + glucose → water + CO2

A bit of trivia

• It is estim

ated that our

bodies have around 100

trillion cells.

• Pancreas cells can live

for a year, some immune

system cells can live

for six weeks, so

me

digestive system

cells li

ve for only

a few days.

A bit of trivia• Cells range in size from 0.1 mm to 0.001 mm.• The motor neuron cell is the longest cell in the human body.• The largest cell in the human body is the female egg (ovum).• The smallest cell in the human body is the male sperm.

Cell organelles

Watch a couple of videos on 'cell membrane', 'cell nucleus', 'mitochondria', 'cytoplasm'.

I

cell membrane

cell wall

mitochondrion

cytoplasm

chloroplastsvacuole

nucleus

A typical plant cell with a cell wall (and chloroplasts). A typical animal cell doesn't have a cell wall.


Some organisms have just one cell. These living things are called single-celled organisms, meaning 'one cell'.

This one cell supports life processes by absorbing food and/or nutrients, expelling wastes, reproducing, and movement.

Single cells

Some organisms, such as plants and animals, are made up of many cells. These living things are called multicellular organisms, meaning 'many cells'.

These many cells work together to support life processes by absorbing food and/or nutrients, expelling wastes, reproducing, and movement.

Many Cells

• A single cell performs all life processes (absorb food, produce energy, expel wastes, reproduce, etc).

• Cell life is short because of the heavy workload.

• The cell is exposed to the environment on all sides.

• An injury can cause the death of the organism.

• Cannot reach a large size.

• Specialised cells within specialised organs perform each of the life processes (absorb food, produce energy, expel wastes, reproduce, etc).

• Cell life is long because the workload is not so large.

• Only specialised cells are exposed to the environment.

• An injury is less likely to cause the death of the organism.

• Can reach a large size.

Drop of Pond water

a. Examine a drop of pond water under a microscope.

1. Can you distinguish the single celled organisms from the multicellular organisms?

Activity

Pond Water Organisms Watch some online videos on 'pond water organisms'. Can you tell the unicellular organisms from the multicellular organisms?

ICell theory

Multicellular organisms can perform functions that single-celled organisms cannot

The whole is greater than the sum of its parts

Cell membrane

Flagellum

Nucleus


A tissue is a group of specialised cells that have a similar structure and function.

Examples:

Muscular tissue consists of similar cells that are able to contract and cause movement either externally (muscle attached to bone and able to produce movement) or internally (heart muscle able to pump blood around the body).

Vascular tissue in plants is able to move fluids and nutrients up and down the stems and leaves of plants.

Tissues

1 What does the term 'multicellular' mean?2 What are 'life processes'?

3 Give two advantages of multicellular organisms over single-celled organisms.

4 Name two single-celled organisms.

5 Name five multicellular animals.

6 Name five multicellular plants.

7 What is a 'tissue'?

8 Give an example of an animal tissue.

9 Give an example of a plant tissue.

ExerciseXylem cells in plants

Materials: Carnations, blue and red food colouring, scissors, knife, microscope.

Method:a. Put 10 drops of blue food colouring in half

a glass of water. Put 10 drops of red food colouring in a second half glass of water.

b. Put a freshly cut carnation in each glass and observe every few hours.

c. Cut a cross section of the stem and observe closely with a microscope.

1. Xylem cells carry fluids up the plants and into the leaves. Can you find them?

2. Any ideas how the fluids move up against gravity?

3. Phloem cells carry nutrients down the stem. Can you find them?

Activity

Xylem and Phloem Tissue Watch some online videos on 'xylem and phloem' tissue in plants.

I

Heart (cardiac) Muscle Watch some online videos on 'cardiac muscle'.

I

Heart muscle tissue is a group of specialised cells that are able to contract and pump blood around the body.

Vascular tissue in plants are groups of specialised cells in plants that are able to move fluids up and down plants.


An organ is a collection of tissues working together to perform a function.

Examples:

The leaf of a plant is an organ that converts light energy into food for the plant. The three main tissues in a leaf are dermal tissue (like a skin), the vascular tissue (carrying water, minerals, food), and the ground tissue (with chloroplasts for photosynthesis).

The stomach is an organ that is made of a variety of tissues. The stomach has muscular tissue to churn the food, glandular tissue to produce digestive juices, epithelial tissue to cover the surface of the stomach.

Organs

The stomach is an organ with layers of tissues and glands.• The mucosa layer is about 1 mm thick.• The mucosa layer secretes enzymes to digest the food and acids to kill bacteria.• The muscle layers contract to churn and mix the food.• The serosa layer holds the stomach in place in our body.

The Stomach Watch some online videos on the functioning of 'the stomach'.

I

The leaf of a plant is considered an organ with a variety of tissues: The dermal tissue is like a skin protecting the leaf.The vascular tissue carries water and minerals to the leaf and food away from the leaf. The ground tissue contains a variety of cells with chloroplasts for photosynthesis.


Organ systems are made of two or more organs working together to perform a function.

The human body has a number of organ systems that work together to keep us alive and functioning.

Examples:

The digestive system is a group of organs that absorb nutrients from foods. Some of the organs in the digestive system that work together are the salivary glands, the pancreas, the stomach, the liver, the small intestine, and the large intestine.

Organ Systems1 What is an organ?

2 What is the difference between a tissue and an organ?

3 The stomach is an organ with a variety of tissues. Give two examples of stomach tissue and the functions they perform.

4 The leaf is considered a plant organ with a variety of tissues. Give two examples of leaf tissue and the functions they perform.

5 What is an organ system? Give three examples of organ systems in the human body.

Exercise

Circulatory SystemTransports nutrients and oxygen to the cells of the body and returns wastes and carbon dioxide. Some organs are:• Heart• Blood vessels• Blood

Nervous SystemMonitors and coordinates internal and external functions. Some organs are:• Brain• Spinal cord• Nerves

Respiratory SystemMoves oxygen from the air into the blood and moves carbon dioxide from the blood into the air. Some organs are:• Lungs• Nose• Trachea

Muscular SystemGives the body its external movement and internal movement (eg stomach, large intestine.Some organs are:• Muscle

Digestive SystemBreaks down food into nutrients suitable for use by the cells of the body. Some organs are:• Mouth• Stomach• Small intestine• Large intestine

Integumentary SystemThe skin protects the body from the outside environment. Some organs are:• Skin• Sweat glands• Hair• Nails

Skeletal SystemSupports and protects the body.Some organs are:• Bones• Tendons• Ligaments

Lymphatic SystemTransfers lymph from between the tissues back to the blood. Some organs are:• Lymph nodes• Spleen• Thymus

Endocrine SystemA system of glands that secretes hormones into the circulatory system. Some organs are:• Thyroid gland• Adrenal gland

Immune SystemThe immune system fights disease.Some organs are:• Adenoids• Tonsils• Spleen

Reproductive SystemA system of organs that work together for the purpose of reproduction.Some organs are:• Ovaries• Uterus• Testicles

Urinary SystemExcretes some body wastes in the form of urine and maintains fluid balance. Some organs are:• Kidneys• Bladder• Urethra

Human Body Organ Systems

3.2 Organ Systems66

The digestive system is a group of organs that absorb nutrients from foods.

Some of the organs in the digestive system that work together are the mouth (teeth and salivary glands), the pancreas, the stomach, the liver, the small intestine, and the large intestine.

Digestive System

RumenOmasum AbosmasumReticulum

Digestive system in a herbivore

Herbivores have a specialised digestive system to handle the difficult job of digesting cellulose. Cellulose is the main component of the cell wall of green plants.

Cows, herbivores, have large molars (teeth) to grind the grass. Cows also have four stomach chambers to digest the cellulose in the grass.

The first chamber softens the grass, with the help of bacteria and is then regurgitated as cud. The cud is chewed with saliva to further breakdown the size of the grass and returned to the first two stomachs. The omasum further digests the grass. The abosmasum absorbs the majority of the nutrients.

esophagus small intestinestomach large intestine

rectum

Digestive system in a carnivore

Dogs have incisors and canines to tear, cut, and crush meat.

Saliva begins digesting the food as it moves into the stomach. The stomach churns and mixes the food with more digestive juices.

In the small intestines more digestive juices are mixed with the food to help in breaking down the protein, fats, and carbohydrates. The walls of the small intestine also absorb nutrients from the broken down food into the bloodstream.

The large intestine absorbs water and ferments fibre using bacteria.

Undigested food, water, and dead bacteria are stored in the rectum.

67 Chapter 10 Energy 67 Chapter 3 Multi-cellular organisms 67

Food digestion in mouth

Materials: Plain biscuit/unsalted cracker

1. Bite, chew, and hold a plain biscuit in your mouth for about 30s. Why has the food become soggy? Why has the food become sweet?

2. Lie on your side and swallow the soggy biscuit. Can you feel/sense where the biscuit has gone? How did the food get to your stomach?

Activity

1 What is the main function of the digestive system?

2 What is the function of the mouth?

3 What is the function of the stomach?

4 What is the function of the small intestine?

5 What is the function of the large intestine?

6 Which digestive system is similar to the human digestive system:

a) herbivore digestive system, or b) carnivore digestive system?

7 Why is the herbivore digestive system different to the carnivore digestive system?

8 Which chamber of the cow resembles the small intestine and large intestine combined?

Exercise

Mouth

Stomach

Small Intestine

Large Intestine

Some organs of the Digestive SystemOrgan Organ Function

• The teeth in the mouth grinds the food into smaller pieces for swallowing.

• The saliva glands moisten the food and secretes enzymes to begin breaking down carbohydrates.

• The stomach churns the food with secreted gastric juices into a 'soup'.

• The gastric juices start breaking down proteins.• The gastric juices also kill harmful organisms.

• Enzymes from the pancreas continue the breakdown of proteins, fats, and starches.

• Most of the nutrients from the digested food is absorbed through the wall of the intestine into the blood stream and then taken to cells of the body.

• Water is absorbed from the wastes.• Many vitamins are also absorbed through the wall of

the large intestine (The vitamins are produced by the millions of bacteria feeding on the waste).

The Digestive System Watch some videos, build digestive systems, use apps on the 'digestive system'.

I

3.2 Organ Systems68

The respiratory system is a group of organs that supplies blood with oxygen from the air and takes carbon dioxide from the blood and puts it in the air.

Some of the organs in the respiratory system that work together are the nose, the bronchi, the lungs, and the alveoli.

Respiratory System

A bit of trivia• Your left lung is smaller than your right lung to make room for your heart.• The total surface area of your lungs is about the size of a tennis court.• On average, men's noses are larger than women's noses.

Your nose is in the scenter of your face.

Respiratory system in an insect

The cells of insects need a supply of oxygen and need to expel carbon dioxide.

Insect have spiracles, small openings, along the sides of their thorax and abdomen.

Oxygen enters the spiracles and passes along a trachea which branches up into smaller and smaller tubes that reach the cells of the body.

Carbon dioxide from the cells of the body follow the same tubes back to the spiracles.

Insect movement causes the air to move in and out of the spiracles.

Airsac

Airsac

Lungs

Respiratory system in birds

Birds have lungs and from seven to nine air sacs. Birds need two breathe-in and breathe-out cycles to move air through their respiratory system. Humans need one breathe-in and breathe-out cycle.

The first breathe-in puts air in the back air sacs.The first breathe-out moves the air to the lungs. The second breathe-in moves the air to the front air sacs.The second breathe-out moves the air out through the nostrils (nares).


Breathing ratesMaterials: Watch/stopwatch1. Measure your breathing rate in 'breaths per

minute' when you are at rest and when you have exercised. Also do this for others.

2. Graph your results and comment.

Activity

1 What is the main function of the respiratory system?

2 Name three main organs in the respiratory system.

3 With a diagram, describe the function of the alveoli.

4 Describe two differences between the bird respiratory system and the human respiratory system.

5 What is common to insect, bird, and human respiratory systems?

6 Why is the left lung smaller than the right lung in humans?

7 Have you noticed that the 'left' in a diagram is on the wrong side. Why?

Exercise

Nose

Bronchi

Lungs

Alveoli

Some organs of the Respiratory SystemOrgan Organ Function

• The nose is lined with hair. The nose filters and moistens the air entering the respiratory system.

• The trachea, or windpipe, is a tube that breaks up into the left bronchi and the right bronchi.

• The bronchi are tubes that allows the flow of air into and out of the lungs.

• The left lung has two lobes and the right lung has three lobes.

• Lungs have a soft spongelike texture.

• The alveoli are sac-shaped bodies inside the lungs.• The alveoli are covered in capillaries.• Oxygen passes through the walls of alveoli into the red

blood cells of the capillaries.• Carbon dioxide passes from the red blood cells through

the walls of the alveoli into the lungs.

The Respiratory System Watch some videos, build respiratory systems, use apps on the 'respiratory system'.

I

Make a spirometer to measure how much air your lungs can hold.

Challenge

Capillary(small blood vessel)

Alveoli

Alveoli

O2

CO2

Right bronchi

Left bronchiRight lung Left lung

Trachea

3.2 Organ Systems70

The circulatory system is a group of organs that transports oxygen, nutrients, and hormones to the cells of the body and transports wastes such as carbon dioxide and urea from the cells of the body to the lungs and kidneys.

Some of the organs in the circulatory system that work together are the heart, the blood vessels, and the blood.

Circulatory System

Circulatory system in a fish

Fish have a single loop circulatory system and effectively a two-chambered heart.

Blood, low in oxygen and high in carbon dioxide, is pumped from the heart, through arteries and then capillaries, to the gills.

Blood, now rich in oxygen and low in carbon dioxide, flows to cells of the body through a network of veins and capillaries.

Blood, low in oxygen and high in carbon dioxide, flows to the heart through a network of capillaries and veins.

gill capillariesventricleatriumbody capillaries

A bit of trivia• The heart can squirt blood 10 metres.• The human circulatory system is estimated to have about 100 000 km of blood vessels.• The average person has between 5 and 6 litres of blood.• 7% of our body is blood.

I had a blood test yesterday, it took a lot out of me.

A blood-sucking arachnid from the moon would be a luna tick.

Circulatory system in amphibians (eg frogs)

Young amphibians have a two-chambered heart, similar to fish, where blood is pumped through the gills and onto the cells of the body before being returned to the heart. The two chambers are the atrium, collecting the blood, and the ventricle, pumping the blood.

Adult amphibians have a three-chambered heart because the gills have been replaced with lungs. There are two atriums, collecting blood from the body and the lungs, and a ventricle pumping blood to the body and the lungs.

Atrium

Atrium

Capillaries in the lungs

Capillaries in the body Ventricle


Heart ratesMaterials: Watch/stopwatch1. Measure your heart rate in 'beats per minute'

when you are at rest and when you have exercised. Also do this for others.

2. Graph your results and comment.

Activity

1 What is the main function of the circulatory system?

2 Name the two main organs in the circulatory system.

3 What is the difference between an artery and a vein?

4 The pulmonary artery carries blood from the heart to the lung. Would this blood be oxygen rich or oxygen poor?

5 Most diagrams of the circulatory system have red and blue coloured blood vessels. What is meant by each colour?

6 A fish has a heart with two chambers and a human has a heart with four chambers. Why do humans have two extra chambers?

Exercise

Heart

Blood vessels

Blood

Some organs of the Circulatory SystemOrgan Organ Function

• The heart has four chambers.• The right atrium collects carbon dioxide rich blood

from the cells of the body. The right ventricle pumps this blood to the lungs.

• The left atrium collects oxygen rich blood from the lungs. The left ventricle pumps this blood to the cells of the body.

• There are three types of blood vessels.• Arteries carry blood from the heart (either O2 rich blood

and nutrients to cells of the body or CO2 rich blood to the lungs).

• Veins carry blood to the heart (either CO2 rich blood from the cells of the body or O2 rich blood from the lungs).

• Capillaries are tiny vessels that exchange nutrients and wastes among the cells of the body.

• The red blood cells transport oxygen and carbon dioxide throughout the body.

• Red blood cells are produced in the bone marrow, live for about three months, and are removed by the spleen.

The Circulatory System Watch some videos, build circulatory systems, use apps on the 'circulatory system'.

I

Red blood cells

Head & Arms

Body & Legs

Lungs

Heart

CO2 rich blood

O2 rich blood

Aorta

Left atrium

Left ventricle

Pulmonary artery

Pulmonary vein

Right atrium

Right ventricle

Make a stethoscope to listen to the heart.Listen to a heartbeat - can you hear a 'lub' then 'dub' with quietness between the 'lub' and 'dub'?

Challenge

3.2 Organ Systems72

The urinary system, or the renal system, is a group of organs that filters wastes from the blood.

Some of the organs in the urinary system that work together are the kidneys, the ureters, the bladder, and the urethra.

Urinary System

A bit of trivia• The bladder can hold 400 to 600 mL of urine.• Your kidneys filter your blood 24 hours per day, seven days per week.• Your kidneys filter about 8 litres of your blood each hour.• Urine only smells after outside bacteria have fed on the urine.

The most important thing to know about becoming a urologist is that you have to be able to go with the flow.

Kidney

Ureter

Bladder

Urethra

Urinary system in a spider

The malpighian tubules in a spider function in a similar way to the kidneys in humans.

The malpighian tubules absorb water and wastes such as urea and amino acids, and water from the surrounding tissues. The urine and wastes then merge with digested foods in the cloacal chamber and are either reabsorbed or excreted.

Malphigian TubulesHeart

Mid gut

Cloacal chamber

Brain

Lung

Fang

Stomach

Spinneret

Urinary system in a horse

The kidneys filter the blood and collect wastes in the form of urine.

The urine is transported from the kidney to the bladder through the ureter by muscular contractions .

When the bladder is full of urine, the muscular walls of the bladder contract at the same time as the sphincter muscles at the neck of the bladder relaxes. The urine is then emptied through the urethra.

Kidney Ureter UrethraBladder


Our kidneys

Materials: Poster / pens etc

Make a poster for the classroom wall about the kidney.

• The functions of the kidney.• What can go wrong?• How to keep a healthy kidney.• Can you live without a kidney?

Activity

1 What is the main function of the urinary system?

2 What is another common name for the urinary system?

3 What is the function of the kidney?

4 What is the function of the ureter?

5 What is the function of the bladder?

6 Place each of the following urinary system organs in order of urinary flow:

urethra, ureter, bladder, kidney.

7 How is the urinary system of a spider similar to that of a human?

8 How is the urinary system of a spider different to that of a human?

Exercise

Some organs of the Urinary SystemOrgan Organ Function

• The kidneys are about the shape of a fist, weigh about 150 grams each, and are just under your rib cage at the small of your back.

• The kidneys filter the blood, removing wastes such as urea and ammonium.

• The kidneys also maintain the correct balance of substances such as water, glucose, amino acids, and electrolytes in the blood.

• The kidneys excrete the urine into the ureter.

• The ureter is a muscular tube that propels urine from the kidney to the bladder.

• The ureter is about 25 cm to 30 cm long.

• The bladder stores urine.• Your brain gives the signal to empty the bladder.

The bladder outlet muscles relax and the bladder squeezes to empty your bladder of urine.

The Urinary System Watch some videos, build urinary systems, use apps on the 'urinary system'.

I

Bladder

Urethra

Ureter

Renal artery

Renal vein

Medulla

Ureter

Kidney

3.2 Organ Systems74

The skeletal system is a group of organs that support the body, protect the body, and help in the movement of the body. Organs of the skeletal system also produce blood cells and regulate hormones.

Some of the tissues in the skeletal system that work together are bone, cartilage, tendons, ligaments, and joints.

Skeletal System

A bit of trivia• You are born with 300 bones. As an adult you will have 206 bones.• Your bone marrow produces two million red blood cells every second.• 1 in 20 people have an extra rib.• The femur is the longest bone in our body.

Who won the skeleton beauty contest?

No body.

You won't believe how many times you will use the names of bones in your years to come.

The major bones of our body

Materials: A skeleton or an unlabelled diagram of a skeleton.

Keep practicising until you are able to point to the major bones of a skeleton (or yourself) and name them.

20 major bones: Cranium, mandible, vertebrae, clavicle, scapula, sternum, ribs, coccyx, humerus, radius, ulna, femur, carpals, metacarpals, phalanges, tarsals, metatarsals, patella, tibia, fibula.

Activity

The Skeletal System Play a couple of the online interactive games about the names of our bones.

I

The Skeletal System Watch some videos about the 'skeletal system'.

I

The Skeletal System

What is osteology?I


Word BankAdd the following words to your word bank by writing the word, and writing a definition of the word.

WordPlant cellAnimal cellCell nucleusMitochondriaMulticellularTissueOrgansOrgan systemDigestive system

The digestive system is a group of organs that absorb nutrients from foods. Some of the organs in the digestive system that work together are the mouth (teeth and salivary glands), the pancreas, the stomach, the liver, the small intestine, and the large intestine.

StomachRespiratory systemAlveoliCirculatory systemHeartUrinary systemKidneySkeletal system

Learning PowerImprove your learning with the following brain exercise:1 Pick out a word.2 Read the definition.3 Try to write it down word for word without looking.4 How many times do you need to look and write before you get it right?5 Repeat until you know all of the words.

1 What is the main function of the skeletal system?

2 Label 20 bones on a skeleton.

Exercise

The sale of human organs should be legal

No. The legal sale of organs would allow the rich to jump to the front of the queue. The poor would miss out. The poor could also be forced to sell their organs to pay debts.

Yes. Many people are dying because there are so few donated organs. Legalising the sale of organs would increase the number of available organs and reduce the black market in organs.

Debate Topic

Gene therapy should be an accepted treatment now

No. Inserting genes into the nucleus of a person's cells have unpredictable results and could even contribute to other genetic diseases. Wait until we know more.

Yes. Gene therapy is a cost-effective way of treating many diseases. It would reduce a massive amount of human suffering and death.

Debate Topic

3.3 Science Knowledge76

The Xylem

1 What is the xylem?

2 What is the phloem?

3 Is capillary action able to rise water to a height of 100 m?

4 Design an investigation to answer the question: Can water rise 1 m through capillary action?

Exercise

How does water get from the ground to the leaves of plants? The leaves can be a hundred metres above the ground.

The water flows in a plant tissue called the xylem. The xylem are long tubes that are connected together in bundles.

Transpirational pull: As water evaporates through the leaves, it pulls up water through the xylem. This process requires that the xylem has a small diameter.

Root pressure: Water moves from the soil into the roots through a process called osmosis (water moves from low concentrations in the soil to high concentrations inside the root).

Some theories as to how water can rise so high through the xylem vessels.

A bit of trivia• The walls of the xylem are

made of lignin which is strong

and tough.• Xylem tissue dies and makes

it easier for water to travel.• Massive forces are needed to

raise water 100 m.

The xylem

Watch some online videos on how the 'xylem' works.

I

The xylem carries water, and minerals, up the stem of the plant. The phloem carries food down the stem of the plant.

The thinner the tube, the higher the water rises - capillary action.


In 1895, Roentgen discovered that an unknown ray could penetrate his body and that the image could be captured on photographic plate.

Roentgen called the unknown rays X-rays.

X-rays made it possible to examine the inner structures of the body without surgery.

X-Rays

1 What did Roentgen discover in 1895?

2 Indicate two medical uses of X-rays.

3 Indicate three other uses of of X-Rays.

4 Why were X-rays called X-rays?

5 How does an X-ray tube work?

Exercise

While X-rays can be harmful, the benefits are such that X-rays have a number of medical uses:

y X-rays are used in medical imaging to examine bone and tissue structure.

y X-rays are used to kill malignant cancer cells through radiation therapy.

X-rays have many other uses: y X-ray microscopy is used to produce high

quality images. y X-ray crystallography is used to decide the

position of atoms in crystals. y X-rays are used in airport security. y X-ray emissions are used to study objects

in space. y X-rays are used to inspect paintings.

One of the first X-ray medical images (1896).

X-ray of a hand showing a pellet (Amakuha, Wikimedia Commons).

An X-ray tube. A high direct current, around10-100 kV, causes electrons to be fired at the anode and producing X-rays on impact.

3.4 Science Inquiry78

Think about and organise an experiment to answer the question.

Planning an experiment is to describe in detail, the step-by-step procedures to follow.

Collect your data and write it in a prepared data table.

Planning & Conducting

Did your experiment provide an answer to the question?

How good was your data?

Would you do anything different if you repeated your experiment?

Evaluating

Summarise the data in the form of a graph or chart to help in understanding the data and to identify relationships.

Charts, graphs, and tables are also a great way of presenting investigation data to others.

The analysis of the data in a graph involves looking for trends, patterns and relationships in the graph.

Are you able to draw a conclusion from your experimental data?

Processing & Analysing

Write a report using scientific language.

Present your report to your target audience using digital technology.

Examples of reports are shown in Chapter 1.

Communicating

Science inquiry skills are important in science, and in any situation that requires critical thinking. The process of thinking in logical steps allows us to answer questions about the world around us.

Science inquiry skills include:

• questioning and predicting.

• planning and conducting.

• processing and analysing.

• evaluating.

• communicating.

Science Inquiry

The independent variable is the variable that is changed. In graphs, the independent variable is plotted on the x-axis.

The dependent variable is the variable that is measured. In graphs, the dependent variable is plotted on the y-axis.

The controlled variables are all of the other variables that are to be kept constant.

Variables

Investigation variables

Watch a couple of 'investigation variables' or 'fair testing' videos.

I


Conduct investigations to answer each of the following questions.

Activity

Science investigations are activities in which ideas, predictions or hypotheses are tested and conclusions are drawn in response to a question or problem.

Investigations can involve a range of activities, including experimental testing, field work, locating and using information sources, conducting surveys, and using modelling and simulations.

Science Investigations

Will more chewing cause more breakdown of starches to sugars in the mouth?

Prediction:

Questioning & Predicting

Well? What is your prediction?

Is body temperature important for the breakdown of starch to sugar in the mouth?

Prediction:



Is the amount of water important for the breakdown of starch to sugar in the mouth?

Prediction:



Do taller people have larger lung volumes?

Prediction:



How to measure lung capacity

Watch a couple of videos on 'lung capacity measurement'.

I

Test for starch and sugar

Watch a couple of videos on 'test for starch' and 'test for sugar'.

I

Starch to sugar

Starch is found in potatoes, rice, and bread.

Saliva has an enzyme, amylase, that will help break starches to sugars.

A drop of iodine will stay dark if starch is present and will turn clear or yellow if the starch has been converted to sugar.

A dentist has to tell a patient the whole tooth.

I've been to the dentist several times so I know the drill.

3.5 Chapter Review80

When ready, cover the information above and answer the questions below.

Some organisms, such as plants and animals, are made up of many cells and are called multicellular organisms, meaning 'many cells'.These many cells work together to support life processes by absorbing food and/or nutrients, expelling wastes, reproducing, and movement.The advantages of multicellular organisms are:

• Specialised cells within specialised organs perform each of the life processes (absorb food, produce energy, expel wastes, reproduce, etc).

• Cell life is long because the workload is not so large.

• Only specialised cells are exposed to the environment.

• An injury is less likely to cause the death of the organism.

• Can reach a large size and have greater access to food.

6 Write the following symbolic equation for respiration in words:

O2 + C6H12O6 → energy + H2O + CO2

7 What does the term 'multicellular' mean?

8 What are 'life processes'?

9 Give three advantages of multicellular organisms over single-celled organisms.

10 Name two single-celled organisms.

11 Name five multicellular animals.

12 Name five multicellular plants.

13 Can you think of an advantage that a single-celled organism might have over a multicellular?

Exercise

1 Draw and label a typical plant cell.

2 Draw and label a typical animal cell.

3 Describe the function of each of the following organelles found in plant cells:

a) cell membrane. b) nucleus. c) mitochondria. d) cytoplasm.

4 Why would you expect to find mitochondria in plant cells as well as animal cells?

5 Why would you expect more mitochondria in a muscle cell than in a pancreas cell?

Exercise

A cell membrane• a thin covering holding and

protecting the cell.• lets oxygen and dissolved

food into the cell.• lets carbon dioxide and

wastes out of the cell.Cytoplasm

• jelly-like substance making up most of the cell.

• where the important reactions take place.

A nucleus• the dark spot in the cell.• has DNA which controls the

action of the cell.

Mitochondria• tiny powerhouses in the cell.• converts glucose into energy

(respiration). O2 + glucose → water + CO2

cell membrane

cell wall

mitochondrion

cytoplasm

chloroplastsvacuole

nucleus A typical plant cell with a cell wall (and chloroplasts). A typical animal cell doesn't have a cell wall.



Organ systems of the body

Circulatory System: Transports nutrients and oxygen to the cells of the body and returns wastes and carbon dioxide.Digestive System: Breaks down food into nutrients suitable for use by the cells of the body.Endocrine System: A system of glands that secretes hormones into the circulatory system. Immune System: The immune system fights disease.Integumentary System: The skin protects the body from from the outside environment.Lymphatic System: Transfers lymph from between the tissues back to the blood.Muscular System: Gives the body its external movement and internal movementNervous System: Monitors and coordinates internal and external functions.Reproductive System: A system of organs that work together for the purpose of reproduction.Respiratory System: Moves oxygen from the air into the blood and moves carbon dioxide from the blood into the air. Skeletal System: Supports and protects the bodyUrinary System: Excretes some body wastes in the form of urine and maintains fluid balance.

A tissue is a group of specialised cells that have a similar structure and function. For example, muscular tissue consists of similar cells that are able to contract and cause movement either externally (muscle attached to bone and able to produce movement) or internally (heart muscle able to pump blood around the body). Vascular tissue in plants is able to move fluids and nutrients up (xylem cells) and down (phloem cells) the stems and leaves of plants. An organ is a collection of tissues working together to perform a function. For example, the stomach is an organ that is made of a variety of tissues. The stomach has muscular tissue to churn the food, glandular tissue to produce digestive juices, epithelial tissue to cover the surface of the stomach.Organ systems are made of two or more organs working together to perform a function. For example, The digestive system is a group of organs that absorb nutrients from foods. Some of the organs in the digestive system that work together are the salivary glands, the pancreas, the stomach, the liver, the small intestine, and the large intestine.

1 What is a 'tissue'?

2 Give an example of an animal tissue.

3 Give an example of a plant tissue.4 What is an organ?

5 What is the difference between a tissue and an organ?

6 The stomach is an organ with a variety of tissues. Give two examples of stomach tissue and the functions they perform.

7 What is an organ system? Give an example of organ system in the human body.

Exercise8 Write a brief description of the function of

each of the following human organ systems:

a) Circulatory system. b) Digestive system. c) Endocrine system. d) Immune system. e) Integumentary system. f) Lymphatic system. g) Muscular system. h) Nervous system. i) Reproductive system. j) Respiratory system. k) Skeletal system. l) Urinary system.

Exercise



1 What is the main function of the digestive system?

2 What is the function of the mouth?

3 What is the function of the stomach?

4 What is the function of the small intestine?

5 What is the function of the large intestine?

6 Name two substances that are absorbed from the wastes in the large intestine.

7 Which digestive system is similar to the human digestive system:

a) herbivore digestive system, or b) carnivore digestive system?

8 Why is the herbivore digestive system different to the carnivore digestive system?

Exercise9 What is the main function of the respiratory

system?

10 Name three main organs in the respiratory system.

11 With a diagram, describe the function of the alveoli.

12 Describe two differences between the bird respiratory system and the human respiratory system.

13 What is common in insect, bird, and human respiratory systems.

14 Why is the left lung smaller than the right lung in humans?

15 Have you noticed that the 'left' in a diagram is on the wrong side. Why?

Exercise

The digestive system is a group of organs that absorb nutrients from foods. Some organs are:Mouth• The teeth in the mouth grinds the food into

smaller pieces for swallowing.• The saliva glands moistens the food and

secretes enzymes to begin breaking down carbohydrates.

Stomach• The stomach churns the food with secreted

gastric juices into a 'soup'.• The gastric juices start breaking down pro-

teins.• The gastric juices also kill harmful organ-

isms.Small intestine

• Enzymes from the pancreas continue the breakdown of proteins, fats, and starches.

• Most of the nutrients from the digested food is absorbed through the wall of the intestine into the blood stream and then taken to cells of the body.

Large intestine• Water is absorbed from the wastes.• Many vitamins are also absorbed through the

wall of the large intestine (The vitamins are produced by the millions of bacteria feeding on the waste).

The respiratory system is a group of organs that supplies blood with oxygen from the air and takes carbon dioxide from the blood and puts it in the air. Some organs are:Nose• The nose is lined with hair. The nose filters

and moistens the air entering the respiratory system.

Trachea and Bronchi• The trachea, or windpipe, is a tube that

breaks up into the left bronchi and the right bronchi.

• The bronchi are tubes that allows the flow of air into and out of the lungs.

Lungs• The left lung has two lobes and the right lung

has three lobes.Alveoli

• The alveoli are sac-shaped bodies inside the lungs.

• The alveoli are covered in capillaries.• Oxygen passes through the walls of alveoli

into the red blood cells of the capillaries.• Carbon dioxide passes from the red blood

cells through the walls of the alveoli into the lungs.


1 Each differently coloured elephant represents a number. The total of each row and each column is shown.

What number does each elephant represent?

A Sweet Trick

2 In which direction must the handle be turned to raise the elephant?

Optical illusions

Search 'optical illusion' images.

I

A Couple of Puzzles

2 The Muller-Lyer illusion. The lines are the same length.

3 The Poggendorf illusion. The line appears to be broken from a distance.

1 The height and the width of the top hat is the same.

24

16

20

18

18 18 22 20



The circulatory system is a group of organs that transports oxygen, nutrients, and hormones to the cells of the body and transports wastes such as carbon dioxide and urea from the cells of the body to the lungs and kidneys. Some organs are:Heart• The right atrium collects carbon dioxide rich

blood from the cells of the body. The right ventricle pumps this blood to the lungs.

• The left atrium collects oxygen rich blood from the lungs. The left ventricle pumps this blood to the cells of the body.

Blood vessels• Arteries carry blood from the heart (either O2

rich blood and nutrients to cells of the body or CO2 rich blood to the lungs).

• Veins carry blood to the heart (either CO2 rich blood from the cells of the body or O2 rich blood from the lungs).

• Capillaries are tiny vessels that exchange nutrients and wastes among the cells of the body.

The urinary system, or the renal systen, is a group of organs that filters wastes from the blood. Some organs are:Kidney• The kidneys filter the blood, removing

wastes such as urea and ammonium.• The kidneys also maintain the correct

balance of substances such as water, glucose, amino acids, and electrolytes in the blood.

• The kidneys excrete the urine into the ureter.

1 What is the main function of the circulatory system?

2 Name the two main organs in the circulatory system.

3 What is the difference between an artery and a vein?

4 The pulmonary artery carries blood from the heart to the lung. Would this blood be oxygen rich or oxygen poor?

5 Most diagrams of the circulatory system have red and blue coloured blood vessels. What is meant by each colour?

6 Draw a labelled sketch of the heart.

Exercise

Aorta

Left atrium

Left ventricle

Pulmonary artery

Pulmonary vein

Right atrium

Right ventricle

7 What is the main function of the urinary system?

8 What is the function of the kidney?

9 What is the function of the ureter?

10 What is the function of the bladder?

11 Place each of the following urinary system organs in order of urinary flow: Urethra, bladder, kidney, ureter.

12 How is the urinary system of a spider similar to that of a human?

13 How is the urinary system of a spider different to that of a human?

14 What is the main function of the skeletal system?

15 Label 19 bones on a skeleton (Label free skeleton images are available on the internet).

Exercise

craniummandible

clavicle

ribshumerusvertebrae

ulna

carpalsradius

metacarpals

femurphalanges

phalanges

patella tibia

tarsalsfibula

metatarsals

sternum


1 Anatomic orientation terms are used to help describe where things are on a person. For example, a mole might be described as lateral caudal right chest. Some terms are:

Lateral: Towards the side. Medial: Towards the middle. Caudal: Towards the feet. Cranial: Towards the head.

Which letter best fits the description 'lateral caudal right chest':

a) A? b) B? c) C? d) D?

2 Mammals have three types of muscle tissue as listed in the table. Which would be the best description of the type of muscle best suited to a jogger. A jogger would rely on muscles that contract at low strength for long periods of time:

a) Involuntary muscle? b) Fast twitch voluntary muscle? c) Slow twitch voluntary muscle? d) Cardiac muscle?

3 Our body controls the amount of sugar (glucose) in our blood, so that it is neither too high nor too low. The glucose comes from the food we eat. After we eat, blood glucose rises, the pancreas releases insulin which causes the blood glucose to drop. If blood glucose drops too low, the pancreas releases glucagon which causes blood glucose to rise.

The table suggests that the patient had a meal at which hour:

a) 2? b) 3? c) 4? d) 5?

Competition Questions

A B

CD

Types of muscleSmooth muscle, or involuntary muscle, used to move the walls of organs such as the stomach, the small intestine, and the urethra.Cardiac muscle, also involuntary muscle, used to pump the heart.Skeletal muscle, or voluntary muscle, used to move bones. There are two types of skeletal muscle:

Type 1, or slow twitch, muscles contract for long periods of time with little force.Type II, or fast twitch, muscles contract quickly and powerfully but tire quickly.

Time (hours) Blood glucose(mmol/L)

12345678

4.54.54.06.06.05.55.04.5


1 The muscles throughout your digestive system repeatedly contract and relax in a wave motion. This is called peristalsis and pushes foods through your digestive system.

Is peristalsis voluntary or involuntary? Explain (Involuntary means to do something without being aware - your heart pumps without you being aware of it).

2 What do you think is meant by retroperistalsis, or reverse peristalsis? Can you give an example of when retroperistalsis might happen?

3 A blood vessel is accidently cut and the blood spurts from the wound. Is the blood vessel a vein or an artery? Explain.

4 Alice has a heart rate of 64 beats per minute when she is sitting at her desk. After Alice has jogged around the oval twice, her heart rate is 123 beats per minute. Why does Alice's heart beat faster when exercising?

5 The following table shows the results of a basic analysis of samples of urine from person A and person B. Which person might have a problem? Explain.

6 Kidney stones are solid crystals that form in the kidney. Kidney stones can continue to grow in size from a grain of sand to the size of a pearl and move through the excretory system.

What problems can large kidney stones cause? Why can kidney stones cause extreme pain?

7 The diagram above shows a simplified view of the circulatory system. a) Given that an artery carries blood from the heart, and a vein carries blood to the heart, indicate whether each of A, B, C, or D are arteries or veins. b) The term pulmonary refers to the lungs. Which is the pulmonary artery? Which is the pulmonary vein? c) Indicate whether each of A, B, C, or D are rich in oxygen or poor in oxygen. d) Indicate whether each of A, B, C, or D are rich in carbon dioxide or poor in carbon dioxide.

8 Study the following concept map for five minutes and then attempt to draw the concept map without looking (This is a very effective method of learning).

Harder Test Questions

A BColour Pale yellow No colourClarity Clear CloudyOdour Nutty SweetGlucose None SomeBlood cells Very few Very few

Body cells

Lungs

heart

A B

CD

Carbohydrates

Glucose Amino acids Glycerol Fatty acids

Enzymes Lipids

Small intestine

Proteins Fats

releases

to digest to digest

to breakdown to to breakdown to to breakdown to

Documents

National Curriculum - drdwyer.com.au - Overview Chapter 1 Science Inquiry Skills 1 Chapter 2 Cells 27 Chapter 3 Multi-cellular Organisms 59 Chapter 4 Reproduction 87