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Contents
PAGE
About this book . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3
Learning to learn: Stay healthy! . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6
1 The basis of life . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2 Nutrition . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3 Interaction and coordination . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4 Reproduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
8
Learning to learn: Graph it! . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5
6
20
32
44
54
The structure of ecosystems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
56
Ecosystems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
66
Learning to learn: The powerful forces of nature! . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
74
7
8
9
Energy from the Sun . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
76
External dynamics of the Earth . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
86
Internal dynamics of the Earth . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
98
Learning to learn: Protect our planet! . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 108
10 Energy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
11 Heat and temperature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
12 Light and sound . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
110
122
130
Voca bulary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 140
Key language . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 148
Learning to learn . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 154
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Learning to learn
ABOUT THIS BOOK
• Look at these illustrations. Match them to the unit titles on the opposite page.
• Then, look through the book and check your answers.
A
B
Unit .........................
D
C
Unit .........................
E
Unit .........................
G
F
Unit .........................
H
Unit .........................
J
Unit .........................
I
Unit .........................
K
Unit .........................
Unit .........................
Unit .........................
L
Unit .........................
Unit .........................
3
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YOU ALREADY KNOW A LOT!
Work with a partner. Try to answer these questions.
THE BASIS OF LIFE
What are the three basic functions necessary
for living things?
REPRODUCTION
What is the difference between sexual
and asexual reproduction?
ECOSYSTEMS
Name five living things you would find in
a rainforest.
HEAT AND TEMPERATURE
A thermometer is an instrument which measures the
temperature of a system. Temperature can measured
on three different scales. Can you name all three?
ENERGY FROM THE SUN
Some parts of the Earth receive more solar energy than others.
Which parts receive most, and which parts least?
INTERACTION AND COORDINATION
Plants react to their environment. Give two
examples of how they do this.
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EXTERNAL DYNAMICS OF THE EARTH
Glaciers are masses of moving ice. How do you think they change the landscape of an area?
INTERNAL DYNAMICS OF THE EARTH
The interior of the planet is hotter than the exterior. Can you name
the different layers that form the Earth?
LIGHT AND SOUND
Light travels in a straight line. At what speed does it travel?
1
UNIT
The basis of life
What do you remember?
• What living beings can you see in the photograph?
• What is non-living matter in this photograph?
• How are living and non-living matter different?
• What common characteristics do living beings have?
• What are the vital functions of living beings?
• What is the basic unit of life?
STUDY A UNIT
Look at page 8, the first page of Unit 1
• How many different sections are there on the page?
What are they about?
• What do you think you will learn about in Unit 1?
Content objectives
Key language
In this unit you will …
• Identify and describe the vital functions
• Learn about cells and their components
• Differentiate animal and plant cells
• Learn about cellular nutrition, respiration
• Discover how cellular division occurs
• Study the effect of temperature
on yeast cell division
Reporting facts
Nutrition comes from food and oxygen.
Expressing purpose
The cells in this seed multiply to develop a new plant.
Giving instructions
Make two sugar solutions.
Giving examples
A disaccharide is formed by two monosaccharides,
such as glucose and fructose.
8
Now look at the rest of Unit 1
Symbols
• What are most of the illustrations about?
• Text recorded on the CD.
• Some words are in bold. Why is this?
• Web tasks and Vocabulary
organiser on the CD.
• How many activities are there in the unit?
• What can you find on page 19? How is this useful?
• More student activities
on the CD.
tivit
ies
• What will you do on the Hands on section, page 17?
1
Ac
• How many sections are there in this unit?
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Stay healthy!
In order to stay healthy, you need to have a balanced diet,
be physically active, and make healthy lifestyle choices.
Gym keeps you flexible and
strong. Do it twice a week.
Diet. A food pyramid helps you create a balanced diet.
Do 60 minutes of moderate
physical activity every day!
The exercise pyramid. Try to be active like the young
WAYS TO ACHIEVE A
Use protection. Wear a
helmet when riding a bike,
a scooter or a skateboard.
Wear a seatbelt in the car.
Use sunscreen regularly,
even when it is cloudy!
Health visits
• Brush your teeth regularly and visit your dentist.
• Visit your doctor periodically for check-ups.
6
peop
HEAL
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Don't spend so much time being inactive!
underweight
normal
overweight
2.0
obese
1.9
1.8
height (m)
1.7
1.6
1.5
weight (kg)
40 50 60 70 80 90 100 110 120 130 140 150 160
Body Mass Index. Healthy weight depends
on age, height and body type. The Body
Mass Index (BMI) is a reliable indicator of
excess weight.
Do recreational activities
3 times a week.
people at the bottom of the pyramid.
HEALTHY LIFESTYLE
Activities
Stay hydrated. Drink plenty
of water, especially when
exercising.
1. Use the BMI calculator on the following web
link to calculate your Body Mass Index (BMI).
http://nhlbisupport.com/bmi/bmi-m.htm
2. Class survey. Design a survey with 6
questions. For example:
Get plenty of sleep. Too little
sleep can affect your growth
and your immune system.
1. Do you always wear a helmet?
2. Do you use sunscreen regularly?
Prepare a poster with your results.
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UNIT
1
The basis of life
What do you remember?
• What living beings can you see in the photograph?
• What is non-living matter in this photograph?
• How are living and non-living matter different?
• What common characteristics do living beings have?
• What are the vital functions of living beings?
• What is the basic unit of life?
8
Content objectives
Key language
In this unit you will …
• Identify and describe the vital functions
• Learn about cells and their components
• Differentiate animal and plant cells
• Learn about cellular nutrition, respiration
• Discover how cellular division occurs
• Study the effect of temperature
on yeast cell division
Reporting facts
Nutrition comes from food and oxygen.
Expressing purpose
The cells in this seed multiply to develop a new plant.
Giving instructions
Make two sugar solutions.
Giving examples
A disaccharide is formed by two monosaccharides,
such as glucose and fructose.
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1. What are the vital functions?
Vital functions refer to the specific
actions which support life.
There are three functions:
• Nutrition function. Living beings
obtain the matter and energy
necessary to sustain life through
this function. Nutrition requires
the intake of food and oxygen.
• Interaction function. Living
beings relate with their
surrounding environment
through this function.
• Reproduction function.
Individual living beings are
produced. This ensures the
perpetuation of the species.
Activities
1. Copy and complete the table.
Vital function
Actions
2. Classify. Which vital function is illustrated by the examples?
a. An oak tree loses its leaves in winter.
b. Flowers appear on a rosebush.
c. A gazelle runs away from a lion.
d. A rabbit eats grass.
e. An apple tree absorbs water through its roots.
Vital functions
Nutrition
Interaction
Reproduction
Autotrophic organisms make
their own organic matter from
inorganic matter.
Animals have receptors which
receive stimuli, and effectors
which produce responses.
Sexual reproduction requires a
male parent and a female parent.
Heterotrophic organisms feed on
organic matter produced by other
beings and transform it into
their own matter.
Plants do not have receptors, but
they still respond to stimuli from
the environment.
Asexual reproduction requires
only one parent.
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2. What are biomolecules?
Biomolecules are the building blocks of life. They also perform important
functions in living organisms. They are mainly composed of carbon,
hydrogen, oxygen, nitrogen, sulphur and phosphorus.
Organic biomolecules are exclusive to living beings. There are four types:
Polysaccharide
• Carbohydrates. These are the most abundant organic compounds, also
known as saccharides. Carbohydrates are made up of molecules called
monosaccharides. These are colourless, crystalline substances with a
sweet taste, which dissolve in water. Examples are glucose and fructose.
Most carbohydrates are responsible for storing and transporting energy.
However, others are structural components, for example, cellulose.
Monosaccharides
Sucrose
Cellulose
Starch
A disaccharide is formed
by two monosaccharides,
such as glucose and
fructose.
A polysaccharide is formed
by many monosaccharides, such
as cellulose, responsible for the
cell wall structure of plants.
Rice contains starch,
a polysaccharide responsible
for storing energy.
• Lipids. These form a huge group of organic compounds which occur
naturally. They are all insoluble in water. Lipids perform many different
functions. For example, fats and oils are used for storing energy.
Phospholipids are fundamental in the structure of cell membranes.
Steroids, such as cholesterol, act as sexual hormones or as
vitamin D. Waxes are produced by animals and plants as protection.
Fats
Activities
3. What are the two most
important functions of
carbohydrates? Give an
example of a carbohydrate
for each.
4. Would you expect the
following foods to contain
carbohydrates or lipids?
Oils
10
Waxes
– sugar
– rice
– banana
– honey
– olive oil
– pasta
– milk
– apple
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• Proteins. These are macromolecules (large biomolecules), with very
complex structures, made up of chains of smaller molecules called
amino acids.
The most important functions of proteins are:
– to give structure to the cells, for example, collagen in the skin
Protein
– to transport substances around the body, for example, haemoglobin
– to regulate chemical reactions, for example, enzymes
– to protect the body from bacteria and microorganisms, for example,
antibodies
• Nucleic acids. These are macromolecules which are formed by the
union of smaller molecules known as nucleotides. Nucleic acids are
found in the genetic material of cells.
There are two types:
Amino acids
– Deoxyribonucleic acid, (DNA), stores all the information necessary
for the functioning and development of living things. DNA is found in
the cell nucleus and makes up the genetic code of the chromosomes.
– Ribonucleic acid, (RNA), participates in the synthesis of proteins.
RNA is found in the cytoplasm.
Inorganic biomolecules
Nucleic acid
Inorganic biomolecules are compounds that are not exclusive to living
beings. However, they are essential for life.
• Water is the most abundant substance in living beings. It makes up
about 65% of your body. It is present in tissues, organs, blood and even
in your teeth. It is used to carry out all chemical reactions. It is also
needed to transport substances and to regulate body temperature.
• Mineral salts form the solid structure of living beings, such as
skeletons. Mineral salts are also involved in chemical reactions;
they are necessary for the transmission of nervous impulses.
Nucleotide
Activities
5. Write down the meaning of these words: monosaccharide, protein, nucleic acid.
6. What functions do proteins carry out? Say examples: Proteins give structure to the cells, …
7. What are nucleic acids and where do you find them in living things?
8. Copy and complete the table for all biomolecules.
Biomolecules
Name
Components
Function
Example
Carbohydrate
monosaccharides
storing and
transporting energy;
making structures
glucose
sucrose
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3. What are cells?
Cells are the structural and functional units of
all living beings.
Prokaryotic cells.
The genetic
material is loose in
the cytoplasm.
Bacteria are
unicellular,
prokaryotic
organisms.
They have three basic structures:
• The cell membrane is the thin layer which
separates the inside of the cell from its
surrounding environment.
• Cytoplasm is the gelatinous, semi-transparent
fluid which fills most cells. It contains structures
called organelles, which are responsible for
cell functions.
• The nucleus carries the genetic (hereditary)
information of living things which is passed from
one generation to the next. Genetic material can
refer to anything from a small fragment of DNA to
the entire genome. A genome is the total set of
genes, in other words, the chemical units of
hereditary information carried by a cell.
Animal cell
nucleus
Eukaryotic cells.
The genetic
material is
enclosed in a
structure called
the nucleus.
Animals and
plants are
multicellular,
eukaryotic
organisms.
Cell membrane. Encloses the
cell and regulates the
substances exchanged
between the inside and the
outside of the cell.
Plant cell
Nucleus. Contains the
genetic material of the cell.
Rough ER (Endoplasmic
reticulum). Where proteins
formed in the ribosomes are
stored and processed.
Cytoplasm. The inside of the
cell which contains the
nucleus and the organelles.
Vacuoles. Sacs which
contain storage or waste
substances. They are much
larger in plant cells.
Vesicles. Transport
substances
Mitochondrion. Responsible
for cell respiration.
Golgi body. Where
substances produced in the
ER are processed.
12
Cell wall. A thick,
rigid layer which
provides support
and protection.
Chloroplast.
Where
photosynthesis
takes place.
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4. What is cellular nutrition?
Cellular nutrition consists of all the processes in which cells obtain matter and
energy to perform vital functions.
The cells take in substances, called nutrients, from the outside. Nutrients are
obtained from food, which is rich in biomolecules: carbohydrates, lipids,
proteins, water, mineral salts, etc. Once inside the cell, the nutrients are
subjected to chemical processes. These chemical processes are called
cellular metabolism.
There are two types of metabolic reactions:
Catabolism. This is the degradation of complex organic substances
into simple substances. It produces energy.
complex
organic
substances
energy
simple substances
Anabolism. This is the production of more complex organic
substances from simple substances. It requires energy from
catabolism or from photosynthesis.
simple
substances
energy
complex
organic
substances
Activities
9. What two differences are there between
animal and plant cells?
10. Test a classmate on cells:
11. Complete with anabolism or catabolism.
a. ... produces complex organic substances.
b. ... breaks down complex organic substances.
A: What is a ribosome?
c. ... needs complex subtances to produce energy.
B: The part of a cell which is ...
d. ... needs energy to produce substances.
12. Where do the cells of living beings obtain nutrients?
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5. How many types of nutrition are there?
According to the type of nutrients taken in by the cell, there are two types of nutrition:
Autotrophic nutrition
Heterotrophic nutrition
Autotrophic nutrition is characteristic of cells
which use an energy source to make their own
organic matter from inorganic matter.
Inorganic matter includes: oxygen, carbon
dioxide, mineral salts and water.
Heterotrophic nutrition is characteristic of cells
which feed on organic matter produced by other
living beings. They transform this organic matter
to obtain nutrients and energy. Heterotrophic
nutrition takes place in the cells of animals, fungi,
protozoa and many bacteria.
Depending on the energy source used, two
processes may take place:
CO2
– Photosynthesis. Energy comes from the Sun.
This takes place in plant and algae cells and
cyanbacteria, which contain chloroplasts.
– Chemosynthesis. Energy comes from chemical
reactions. This takes place in some bacteria.
3
1
H2O
O2
2
O2
CO2
1
mineral
salts
sunlight
3
4
energy
H2O
other functions
complex organic matter
2
simple
organic
matter
energy
other functions
4
complex organic
matter
1. The cell takes in water, carbon dioxide and mineral
salts from the outside. Using sunlight, organic
matter is produced. In the process, oxygen is
released from the cell.
2. Part of the organic matter produced is used in the
mitochondrion, where catabolism takes place.
Using oxygen, energy and inorganic substances
(water and carbon dioxide) are produced.
3. As a result of catabolism, carbon dioxide is
produced and released outside.
4. Using energy from catabolism and simple
molecules, complex organic molecules are
produced (anabolism).
14
simple
organic
matter
1. The cell takes in organic matter from the outside
made by other organisms.
2. Part of this organic matter is used in the
mitochondrion, where catabolism takes place. Using
oxygen, energy and inorganic substances are
produced.
3. As a result of catabolism, carbon dioxide is produced.
Carbon dioxide is toxic, so it is released outside.
4. Using energy from catabolism and simple organic
molecules, complex organic molecules are produced
(anabolism).
Activities
13. What type of nutrition takes place in human
cells? In a spinach leaf?
14. Which type of nutrition ...
a. produces water and carbon dioxide?
b. takes in water and mineral salts?
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6. What is cellular respiration?
Respiration is the release of energy from organic substances
into living cells. All cells need energy to carry out the vital
functions.
Cellular respiration describes the metabolic reactions and
processes which take place in a cell to obtain chemical
energy from specific organic molecules.
First, the cell takes in organic substances (glucose), and
oxygen. Then, it breaks down those substances into simpler
substances, such as carbon dioxide and water. At the same
time, energy is released.
Activities
15. What happens during cell
respiration? Complete the
flow chart below. Use the
basic respiration equation.
Glucose
+
The basic equation for respiration is:
→
Glucose + O2
organic substances
(glucose)
H2O + CO2 + chemical energy
Water
+
oxygen
+
energy
water
carbon dioxide
Cellular respiration takes place in the cell mitochondrion.
Michondria are present in all eukaryotic cells.
16. Is cellular respiration a
catabolic or an anabolic
reaction? See page 13.
17. Make a drawing of cellular
respiration in a cell
michondrion. Label the
drawing. Then describe the
process to a partner:
First, the cell takes in organic
substances and oxygen. Then, …
Fermentation is the process by which cells release energy in
the absence of oxygen. Fermentation takes place in all living
things, but especially in some bacteria and yeasts.
Did you know that...?
Many unicellular bacteria and fungi
obtain energy through
fermentation. Fermentation is
necessary for making bread, wine,
yogurt and cheese.
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7. What is cellular division?
Cellular division is a process by which a cell, known as the parent cell, divides
into two or more cells, called daughter cells.
• In unicellular organisms, cellular division replicates an entire organism and
new individuals are formed. As a result, there is an increase in the population.
Binary fission is found in bacteria and protozoa. Example of
one type of cellular division typical of unicellular organisms.
Multiple fission is found in some types of algae and protozoa.
– Binary fission. First, the nucleus of the parent
cell divides into two identical nuclei. Then the
parent cell divides into two identical daughter
cells of the same size. These then grow to
become adult cells.
– Multiple fission. First, the nucleus of the
parent cell divides into several nuclei. After the
nuclear divisions are complete, the cytoplasm
separates. Then each nucleus becomes encased
in its own membrane to form an individual cell.
• In pluricellular organisms, cellular division results in an increase in the
number of cells of an organism. This increase is reflected in the growth
or repair of damaged parts of the organism.
A
B
C
The cells in this seed multiply and a new plant develops.
Activities
18. What is the main result of cellular division in unicellular organisms? How does it differ from cellular
division in pluricellular organisms?
19. Choose one of the types of unicellular cell division. Draw the process and describe it.
20. Look at the photos of the plant. Write a sentence to describe what is happening in each picture.
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Hands on
Studying the effect of different temperatures on yeast cell division
Materials
– yeast and sugar
– an eyedropper
– cover slips
– warm water
– two glasses
– a measuring glass
– slides
– a microscope
1. Prepare the experiment.
Make two sugar solutions in the glasses. For each solution, dissolve 11/2
tablespoons of sugar in 250 ml of warm water. Then, dissolve one
teaspoon of yeast in each solution.
2. Experiment. Part I
• Make slides of the solutions. Place a few drops of each solution
on a different slide using an eyedropper. Next, cover the drops with
a cover slip. Then, place the slides under the microscope.
• Draw what you see and record the number of cells.
• Cover the glasses and let them stand for 24 hours. Label
one glass “cold solution” and the other “warm solution”.
Next, place one glass in the refrigerator, and the other in
the oven, at 37 ºC.
3. Formulate a hypothesis.
If colder temperatures enhance cell division, the cold solution
will show a higher number of cells. However, if warmer
temperatures enhance cell division, the warm solution will
show a higher number of cells.
5. Interpret the results.
4. Experiment. Part II
• After 24 hours, prepare new slides of each yeast solution.
Observe them under the microscope.
• How do the results for Part I
and Part II compare?
• Draw what you see and record the number of cells.
• Is cell division enhanced by cold
or warm water temperature?
Number of cells
initially
Number of cells
after 24 hours
Cold solution
Warm solution
Activities
21. Look at the cells using different magnitudes. How does this affect what you see?
22. What could you infer about the rate of yeast cell division at room temperature?
23. Design a new experiment and formulate a hypothesis:
How does the concentration of sugar in the solutions affect yeast cell division?
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28. Which of the following structures are found only in
animal cells, only in plant cells, or in both?
24. Copy and complete the table.
Organic biomolecules
Function
Examples
Carbohydrates
Lipids
a. mitochondria
b. nucleus
d. chloroplasts
e. vacuoles
c. cell wall
29. Place the following tissues and organs in order,
based on their water content.
Proteins
Nucleic acids
25. Proteins are formed by chains of 20 different amino
acids.
lungs: 71%
muscles: 75%
liver: 70%
kidney: 61%
blood: 79%
brain: 85%
bone tissue: 22%
teeth: 10%
30. Saccharomyces cerevisiae is a unicellular fungus,
yeast, which is used to make bread. In the absence
of oxygen, it breaks down the sugars in flour,
producing alcohol (ethanol) and carbon dioxide.
a. Imagine that proteins were made up of only two
different amino acids (called aa1 and aa2). Write
the possible kinds of proteins combining the
amino acids in a chain of three. For example:
aa1 + aa1 + aa1.
a. What catabolic process is the yeast performing?
b. The carbon dioxide released by this process is
responsible for the sponginess of the bread.
What happens to the alcohol?
b. Changing one amino acid in a chain can produce
a completely different protein.This fact is related
to the wide variety of living things on Earth.
True or false?
31. Study the diagram of the metabolism of a cell.
a. Label the numbered organelles.
26. Classify the cells: autotrophic or heterotrophic.
a. Leaf cells in an oak tree
b. Label each letter with its substance.
b. Muscle cells in a person
c. What kind of cell is it?
c. Root cells in a geranium
d. What kind of nutrition does it represent?
e. What living beings have this type of nutrition?
27. These are the two main types of cells.
a. What kinds of cells are they? Label them.
1
A
B
b. Name the numbered organelles.
C
c. Which organelles and structures are only present
in one type of cell? Which are common to both?
A
G
D
B
1
4
2
1
2
3
E
3
2
6
5
4
F
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THE BASIS OF LIFE
What should you know?
Vital
functions
• Nutrition function. Process in which living beings obtain the
matter and the energy necessary for life.
• Interaction function. Process in which living beings relate with
their surrounding environment.
• Reproduction function. Process by which new individual
living beings are produced.
Organic and
inorganic
biomolecules
Biomolecules are the building blocks of life. They include:
• Organic biomolecules.
– Carbohydrates – Lipids – Proteins – Nucleic Acids
• Inorganic biomolecules. Water and mineral salts
Cells
Cellular
nutrition
Cellular
respiration
Cellular
division
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• Cells are the structural and functional units of all living
organisms. They have three basic structures:
• Cell membrane
• Cytoplasm
• Nucleus. With genetic material
According to their genetic material, cells can be prokaryotic or
eukaryotic. They can be plant or animal cells.
• Cellular metabolism includes two types of metabolic reactions:
– catabolism
– anabolism
Depending on the type of nutrients, cellular nutrition can be:
• Autotrophic. Characteristic of cells which make their own
organic matter from inorganic matter using an energy source,
mainly sunlight.
• Heterotrophic. Characteristic of cells which feed on organic
matter produced by other living beings.
Describes the metabolic reactions to obtain energy
from specific organic molecules.
This is the process by which a cell divides into two cells,
called daughter cells.
Projects
INVESTIGATE one of the four types of organic biomolecules. Explain its importance in everyday life. Give examples.
INVESTIGATE and make a poster about the different types of cell division.
WEB TASK: Search for signs of life on another planet.
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