PL AR RSO P3L20 Exploring Materials IV WS_1

Primary 3

Rocket Science OEQ

Name ______________
Tutor
Topic FUNGI AND BACTERIA II (LESSON 9)

______________

FUNGI AND BACTERIA II (LESSON 9)

Primary 3: Rocket Science OEQ

Lesson Outline

• Notes
• Activity 1: Concept Recall
• Activity 2: Open-ended Questions
• Activity 3: Science in Daily Life

2

Primary 3: Rocket Science OEQ

BACTERIA(SINGULAR: BACTERIUM) – NOTES
Bacterium can be found in places such as plants, animals, soil, air and water.
They are also found on our skins and in our intestines. They are micro-organisms
and can only be seen under the microscope. Bacteria come in many shapes and
sizes. Fungi and bacteria are called decomposers. They break down dead matter
into nutrients.
Examples: Cocco, bacillius, E.coli etc

Characteristics of bacteria:
• Bacterium can be found in places such as plants, animals, soil, air and
water.
• They are micro -organisms and can only be seen under the microscope.
• Bacteria come in many shapes and sizes.

Where are bacteria found?

AR Model – Bacteria

• Bacteria are found everywhere such as in plants, animals, soil, air and
water including our bodies.

• Bacteria feed on other living things or dead matter. Tooth decay is
caused by a type of bacteria which feeds on food residuefound on
teeth. It is important to brush our teeth before going to bed to avoid
bacteria growing on the teeth.

• We should also wash our hands after using the washroom to avoid
bacterial infections.

3

Primary 3: Rocket Science OEQ

BACTERIA(SINGULAR: BACTERIUM) – NOTES
How do bacteria obtain food?
Most bacteria cannot make their own food. They feed on other living things which
may be dead or alive.
Some bacteria can survive extremely high temperatures. They have been found
living in the deep sea, where temperatures are as high as 105 degrees Celsius.
That is hotter than boiling water.
How do bacteria reproduce?
Bacteria reproduce by binary fission. In this process, the bacterium, which is a
single cell, divides into two identical daughter cells.
What are the harmful effects of bacteria?
Some bacteria are harmful because they cause illnesses such as pneumonia and
influenza, which can be fatal.
Contaminated water carries bacteria which cannot be seen with the unaided eye.
When we drink this water, we may get diarrhea or fever.
Harmful bacteria such as salmonella can spoil food. Some food and drinks that
are left outside spoil quickly.An example is milk. Bacteria will grow quickly in milk
which is left outside and cause it to spoil.
Raw meat often contains harmful bacteria. Meat must be kept in the freezer to
slow down the growth of bacteria. Meat must be cooked properly to kill the
bacteria in it. This makes sure that we do not fall sick when we eat the meat.

4

Primary 3: Rocket Science OEQ

BACTERIA(SINGULAR: BACTERIUM) – NOTES

Uses of bacteria:

• Our body contains useful bacteria which help to digest food. Some
bacteria are used in the production of food such as, cheese, vinegar,
yoghurt, soy sauce and fermented food.

• These bacteria help with our digestion and are generally healthy for our
body.

• Lactobacillus is a type of bacteria found in food such as yoghurt.
Lactobacillus can also be used to make food such as vinegar and
cheese.

• Some bacteria are used in making medicines, such as antibiotics.
Antibiotics are used to cure bacterial infections.

Probiotic drink Pasteurisedmilk

Louis Pasteur was a famous French scientist who discovered pasteurisation.
Pasteur discovered a way to kill the bacteria in the wine and later in milk.
Pasteurisation was later used in the production of milk which keeps the packaged
milk fresh for a longer period.

5

Primary 3: Rocket Science OEQ

BACTERIA(SINGULAR: BACTERIUM) – NOTES
What are bacteria?

https://www.youtube.com/watch?v=AaN8pSmtyV4
Discussion Questions
1. Name the three factors which classify bacteria as living organisms?
2. What are bacteria that cause diseases known as?
3. How can we prevent the spread of bacteria?

6

Primary 3: Rocket Science OEQ

Activity 1 – Concept Recall

1. Read the following statements and write ‘T’ if it is true and ‘F’ if it is false.

Statement T/F
1. All fungi are edible.
2. Bacteria are micro-organisms.
3. Penicillin is made from fungi.
4. We should wash our hands with soap after using

the washroom.
5. Fungi can make their own food.

2. Dylan observed two different types of living things using a microscope as
shown below.

Living thing X Living thing Y

(a) Why does he need to use the microscope to observe the living things?

(b) Dylan managed to find out more about the group that they belonged to
as well as their methods of reproduction. However, some information
was missing. Complete the missing information in the box below.

Living thing X Group Method of
Living thing Y Fungi reproduction

(ii) (i)

By splitting into two

7

Primary 3: Rocket Science OEQ

Activity 2 – Open-ended Questions

1. Ali baked a cake. He left the cake on the table to cool down. Then, he cut the
cake into two parts and put each part on plates, A and B. The table shows
what he did to both parts of the cake.

Plate A The cake was wrapped in a plastic film.
Plate B
The cake was moistened with water, then
wrapped with a plastic film.

Cake wrapped
with plastic

Plate A Plate B

(a) On which plate would mould first appear on the cake? [1]
Give a reason for your answer.

8

Primary 3: Rocket Science OEQ

Andy had a medical condition in which fungus grew on his foot, as shown
below.
Mold fungal infection

(b) Based on the experiment above, explain how wearing shoes and [1]
socks will lead to more fungus growing on Andy’s foot.

9

Primary 3: Rocket Science OEQ

2. Mr. Tan carried out an experiment to find out if garlic juice is good at killing
bacteria. He prepared three petri dishes, A, B and C, as shown in the table
below.

Petri dish Things in the petri dish
A
B 10 ml of milk only

C 10 ml of milk and a small amount of Bacteria E.

10 ml of milk and a small amount of Bacteria E and
garlic juice.

He recorded the size of the bacteria colony in the table below.

Petri dish Size of bacteria colony (mm)

A Day 1 Day 2 Day 3 Day 4
B 0 7
C 0 23 37
0 0
48

00

(a) In which petri dishes are the bacteria growing? [1]

(b) Where do you think the bacteria came from in petri dish A? [1]

10

Primary 3: Rocket Science OEQ

(c) Do you think garlic juice is good at killing bacteria? Support your [1]
choice.

3. Study the two organisms as shown below.

OrganismA Organism B

(a) Which group of living things do the organisms A and B belong to? [2]

OrganismA:

Organism B: [2]

(b) State the difference between the organisms A and B, in how they
obtain food and reproduce.

(i) How they obtain food

(ii) How do they reproduce

11

Primary 3: Rocket Science OEQ

Activity 3 – Science in Daily Life: How to identify puffball mushroom from
poison puffball mushroom or common earthball.

https://www.youtube.com/watch?v=HfdEuoG-f2I

Discuss Answer

Before the video Puffball mushrooms
are huge white ball like
mushrooms which are
edible. They can be
mistaken with the
other poisonous
mushrooms which look
similar. Let’s see how
we can identify real
from the false one.

12

Primary 3: Rocket Science OEQ

Discuss Answer

0:58 What would a real
1:00 puffball mushroom
look like from inside?

What 2 things would
you find in a fake
puffball mushroom?

13