Download 1 Life processes

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1.1
Life processes
Food wheels and food pyramids
Scientists around the world study food and do
experiments to learn what types of food are healthier.
They write about their investigations in scientific
magazines. However, they use very difficult words
so their texts are very hard to understand!
Fortunately, health experts have an easier way
to explain this information. They use food
wheels and food pyramids, which show
us how much we should eat from each
food group. The foods in the biggest
spaces are the ones we should eat
the most of.
We can use these drawings to
choose the best foods for
a healthy diet!
Read and understand
What types of food are healthier?
Where do scientists write about their texts?
Why are these texts so difficult to understand?
What are food wheels and food pyramids?
Look at the food pyramid. Which food group
is in the biggest section? Why?
SPEAKING. What is your favourite food?
Is it healthy? Discuss with your classmates.
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KNOW HOW TO
Describe the processes
of nutrition, sensitivity
and reproduction.
Name the systems and
organs involved in each
life process.
FINAL TASK
Identify healthy diets.
WHAT DO YOU REMEMBER?
Life processes and nutrition
Life processes are necessary to
maintain life. They are carried out by
living things.
Nutrients are useful substances in
food.
1
Name the life processes.
2
Name the main nutrients in food.
3
Look at the photo. What nutrients
are contained in the different
types of food?
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Nutrition
1.2
Some people think that nutrition and eating
food are the same process, but nutrition
is much more.
Eating food is something that you do
several times a day. Nutrition is a constant
process that takes place inside your body.
The process of nutrition
Nutrition is the process which provides your
body with all the nutrients and energy that
are necessary for life.
You need energy to do all kinds of
activities, such as walking, playing and
thinking.
Your body needs nutrients to grow and
to function properly.
Your body obtains energy and nutrients from
food during the process of nutrition. 1
Processes involved in
nutrition
Nutrition begins when you take in food.
It involves four processes:
Digestion. During this process, you absorb
the nutrients your body needs from food.
Respiration. During respiration, you
breathe in air. You need oxygen from air
to obtain energy from food.
Circulation. Circulation moves oxygen
and nutrients throughout your body.
Excretion. During excretion, you expel
the waste materials that your body does
not use.
Nutrition involves four processes:
digestion, respiration, circulation and
excretion.
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Nutrition is the process of obtaining energy
and nutrients from food.
WORK WITH THE PICTURE
What nutrients can you identify in the
picture?
Can you name other nutrients to have
a healthy diet?
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1.3
1.4
Systems involved in nutrition
The different processes of nutrition take place in different parts
of the body, called systems.
The digestive system.
This system absorbs nutrients.
The main organs are the
stomach and the intestines.
The circulatory system.
This system moves blood
around your body. The
main organ is the heart.
blood vessels
heart
stomach
intestines
The respiratory system.
We breathe in air. The main
organs in this system are
the lungs.
lungs
trachea
The excretory system.
This system expels waste
from the body. The main
organs are the kidneys.
kidneys
Nutrition involves the digestive, respiratory,
circulatory and excretory systems.
ACTIVITIES
1
SPEAKING. Why is the process of nutrition necessary?
Tell your partner.
2
Is eating food the same as carrying out nutrition? Explain.
3
What are the main processes involved in nutrition?
What are the main organs involved?
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Sensitivity
1.5
The process of sensitivity
The process of sensitivity is the ability to
detect and respond to changes in the
environment.
First, you receive information from your
surroundings. This information comes from
your senses. Then, your body processes
the information and decides on a response.
Finally, you carry out this response. 1
Sensitivity is a constant process. You are
always using your senses, even if you do
not notice. For example, if you walk down
the street, you hear birds, you smell
flowers, you see other people, etc.
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The boy is responding to changes
in the environment.
The process of sensitivity involves the
sense organs, the nervous system and the
locomotor system.
the sense
organs
the nervous
system
the locomotor
system
The nervous system
The nervous system is made up of the brain
and the nerves.
brain
The brain receives information from the
sense organs. Then, the brain interprets
this information and decides what to do. It
sends the orders to the locomotor system.
nerves
The nerves have two main functions:
– They carry information from the sense
organs to the brain.
– They carry orders from the brain to the
locomotor system. 2
The nervous system is made up of the
brain and the nerves.
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The nervous system.
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The locomotor system
WORK WITH THE PICTURE
The locomotor system allows us to move our body. It is
made up of the skeletal system and the muscular system.
Which bones are near the
fibula?
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The skeletal system is made up of all the bones in our
body. Bones meet at joints. Some joints allow bones to
move.
Describe the cranium.
Where is it found?
Where are the biceps
muscles found?
The muscular system is made up of all the muscles in
our body. Muscles are joined to bones by tendons.
Tendons help our body to move.
The skeletal
system
cranium
clavicle
Which muscles are found
in the trunk?
The muscular
system
vertebrae
humerus
ribs
ulna
pelvis
deltoid
pectorals
biceps
abdominals
radius
femur
quadriceps
fibula
tibia
The locomotor system allows us to move our body.
It is made up of the skeletal and muscular systems.
3
The locomotor system is
made up of the skeletal
and muscular systems.
ACTIVITIES
1
THINK ABOUT IT. Think of an example of the process of sensitivity.
Explain it to your partner.
2
Explain the process of sensitivity using these words.
sense organs brain nerves locomotor system
3
WRITING. What is the function of joints and tendons in the locomotor
system? Explain.
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Reproduction
1.8
The process of reproduction
The process of reproduction allows us to
have offspring similar to ourselves.
People have sexual reproduction. This
means a male and a female have to come
together to reproduce. Because of this,
children usually look like their mother and
father, although they are different to both of
them. 1
People are viviparous. This means that
babies develop in their mother’s womb, also
called the uterus. A new baby is born after
nine months.
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Identical twins look exactly the same.
The organs of reproduction
Male reproductive organs and female
reproductive organs are different. 2
These organs develop during the stage
of adolescence.
WORK WITH THE PICTURE
Draw a table with two columns. Write the
names of the male and female reproductive
organs in each column.
uterus
urethra
penis
testicles
2
Male and female reproductive organs.
Reproduction is the ability to have offspring similar
to ourselves.
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ovaries
vulva
vagina
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a few weeks
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three months
Pregnancy
six months
3
nine months
A baby grows and develops in its mother’s
uterus.
The baby develops and becomes larger
inside the mother’s uterus. This period is
called pregnancy and lasts about nine
months. 3
The baby receives food and oxygen from
the mother. It grows and transforms. Its
shape changes and its organs develop,
until it is ready to be born and live outside
its mother’s uterus.
The newborn baby
Newborn babies need constant attention
and care from their parents. They drink their
mother’s milk or artificial milk from a
bottle. Babies cannot speak or walk and
they do not have teeth. Babies cry to
express themselves, and they depend on
their parents for everything.
However, babies grow very fast. One year
after birth, they say their first words, take
their first steps and grow their first teeth.
The baby develops in the mother’s
uterus for nine months. Newborn
babies drink their mother’s milk and
depend on their parents for everything.
ACTIVITIES
1
WRITING. Define these words
in your notebook.
sexual reproduction
viviparous
2
Are male and female reproductive
organs the same? When do they
develop?
3
ICT. Search the Internet for
information about Caesarian
sections. Then, write a brief
definition.
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occasionally
KNOW HOW TO
Identify healthy diets
There are many food wheels and food pyramids.
several times
The NAOS pyramid was designed to promote
a healthy lifestyle.
Observe the pyramid.
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It looks like a means of transport.
a week
Which one?
2
There is not only food in the pyramid.
3
every day
What else can you see?
There are food groups to eat every
day, several times a week
and occasionally.
Copy this table in your notebook
and complete it with the information
in the NAOS pyramid.
drink water
A hea
lthy lifestyle
food
every day
several times a week
Use the pyramid.
4
Look at the pictures. They show what Jane and Ben
had for lunch.
Which meal is healthier? Explain why.
A
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B
occasionally
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FINAL ACTIVITIES
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SUMMARY. Copy and complete with these words.
sexual – locomotor – sense – circulatory – respiratory –
digestion – nutrition – respiration – food – excretion –
changes – nervous – reproduction – viviparous
The process of
provides your body with energy and
nutrients from
. Nutrition involves many processes:
takes place in the digestive system; circulation takes
place in the
system;
takes place in the
system and
takes place in the excretory system.
Sensitivity is the ability to detect and respond to
environment. The process of sensitivity involves the
organs, the
system and the
system.
in the
is the ability to have offspring similar to ourselves.
People have
reproduction. They are
because babies start developing in their mother’s womb.
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VALUES EDUCATION. Men and women are physically
different.
Does this mean that we can treat them differently? Discuss
with your classmates.
3
THINK ABOUT IT. When you are asleep and a fly lands on
your nose, what does your hand do? Is this an example
of sensitivity? Explain.
Show your skills
Choose one of these activities:
A. Search for information about one of
the systems from the unit and draw
a picture. Label all the organs and
describe their function.
B. Make your own representation of
the NAOS pyramid. Use drawings,
photos or make a collage.
C. Imagine a pair of identical twins. Draw
them and write a short description of their
physical appearance and personalities.
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