SCIENCE F5 CHAPTER 1B ppt

MrMpoilam 2021

MICROORGANISMS

SCIENCE FORM 5 KSSM

Subtopics

1.1 World of Microorganisms

1.2 Useful Microorganisms
1.3 Prevention and Treatment of

Diseases Caused by
Microorganism

World of Microorganisms

Prepared by: Nurulkamilah binti Khairir

1.1.1 Communicate about microorganisms

1.1.2 Conduct an experiment to show the
presence of microorganisms

1.1.3 Conduct an experiment to investigate factors
that affect the growth of microorganisms

Microorganisms

Microorganisms are
minute organisms that
cannot be seen with the
naked eye.

Microorganisms can only
be seen with the help of a
microscope

Normal flora

Normal flora refers to the
microorganisms found in
organisms including
humans and animals
which do not cause
illness

Normal Flora Staphylococcus sp.
Streptococcus sp.
Upper part of
respiratory tract Staphylococcus sp.
Corynebacterium sp.
Skin
Escherichia coli
Small intestine Lactobacillus sp.
Urethra Streptococcus sp.

Staphylococcus sp.
Corynebacterium sp.

Importance of normal flora

For human health

COMPETES VITAMINS GROWTH OF ANTIBODIES
PATHOGENS BODY TISSUES
Consists of Stimulates the
Competes with bacteria that Stimulates the production of
pathogens to synthesise growth of body antibodies that
obtain nutrients vitamin B12 and tissues such as fight pathogens
and prevent the vitamin K colon tissues and and diseases
formation of tissues in the
colonies of digestive tract
pathogens

Classification of Microorganisms

Fungi

Algae

Protozoa

Bacteria

STUDENTS’ PRESENTATION Viruses

Activity 1.1

Page 16 Science Form 5 KSSM Text Book

The Presence of Microorganisms

Experiment 1.1 Experiment 1.2

Aim Aim

To compare the growth of bacteria on sterile nutrient To study the effect of several
agar that has been streaked with: factors on the growth of
(a) Unwashed finger Bacillus sp.
(b) Fingers that have been washed with water only
(c) Fingers that have been washed with soap and

water

Social

Distancing

2m

Experiment 1.1











Factors that Affect the Growth of
Microorganisms

HUMIDITY • Damp conditions promote the growth and
LIGHT reproduction of microorganisms

TEMPERATURE • Dry conditions cause microorganisms to
pH VALUE become less active and retard their growth
NUTRIENT
• Microorganisms which possess chlorophyll
require light to carry out photosynthesis

• Microorganisms such as fungi and bacteria
grow better in the dark

• Exposure to UV light can kill microorganisms

• Temperatures of 35 Oc – 40 oC are the optimum
temperatures for the growth of microorganisms

• Low temperatures retard the growth of microbes
• Too high – kill microorganisms

• pH 7 (neutral) is the optimum pH
• There are certain microbes that can live in

slightly acidic/alkaline environments

• Presence of sufficient nutrient, rate of
growth of microbes increases

• The growth of microbes will be retarded
even in the presence of nutrient when other
factors are limiting

Experiment 1.2

Page 20 Science Form 5 KSSM Text Book



Formative Practice 1.1 (page 27)

1. What are microorganisms?

Microorganisms are minute organisms that cannot be seen with the
naked eye.

2. (a) Name five groups of microorganisms.
(b) What are the characteristics used to classify microorganisms
into five groups?

(a) Fungi, algae, virus, protozoa, virus
(b) Size, shape, nutrition, habitat, methods of reproduction

3. Name the group of microorganisms that reproduces asexually
through the formation of spores.
Fungi and bacteria

4. State two basic structures that make up a virus.
Nucleic acid threads (DNA or RNA) and capsid (protein layer)

5. State five factors that affect the growth of microorganisms.
Temperature, pH, nutrient, humidity, light

6. Figure 1 shows a type of microorganisms
(a) What is the group of the microorganism shown?
(b) (i) What is the structure labelled X?
(ii) State the function of this structure.

(a) Protozoa
(b) (i) Pseudopodium

(ii) To move and engulf food during phagocytosis

Useful Microorganisms

Prepared by: Nurulkamilah binti Khairir

1.2.1 Justify the application of useful
microorganisms in life

1.2.2 Generate ideas on the potential use of
microorganisms in biotechnology and
sustainability of the environment

Agriculture 2. Nitrifying bacteria

1. Animal digestion

Bifidobacteria sp.

Industry 2. Food

1. Bevarage

Lactobacillus bulgaricus Yeast

Industry Yeast

3. Leather goods

Lactobacillus bulgaricus

Medicine 2. Antibiotics like penicillin

1. Hormone like insulin

Recombinant DNA of E. coli Penicillium chrysogenum

Medicine

3. Vaccines

Activity 1.2

Page 29 Science Form 5 KSSM Text Book

Activity 1.3

Page 29 Science Form 5 KSSM Text Book

Potential Use of Microorganism in Biotechnology
and Sustainability of the Environment

Eco Enzyme Lactobacillus sp.

Cleaning Solution Potential Use Bacterial Serum

Natural product obtained Use to treat wastewater
and sludge in drainage
from fermentation of systems

agricultural waste such

as fruit and vegetable

waste 1 2

Eco Enzyme Cleaning Solution

Natural product obtained from fermentation of agricultural waste such
as fruit and vegetable waste

Difference between eco enzyme cleaning solution
and chemical substance

Making an eco enzyme cleaning solution

Homemade Citrus Enzyme Cleaner and Scrub

Lactobacillus sp. Bacterial Serum

Use to treat wastewater and sludge in drainage systems

Activity 1.4

Page 31 Science Form 5 KSSM Text Book



Formative Practice 1.2 (page 32)

1. Name two examples of useful microorganisms in each of the
following fields:
(a) medicine Recombinant DNA of E. coli, Penicillium chrysogenum
(b) agriculture Bifidobacteria sp., Nitrosomonas sp.,
(c) industry Yeast, Lactobacillus bulgaricus, Bifidobacteria sp.

2. State two examples of food that use microorganisms and name
the microorganisms

Bread/Alcoholic beverage : Yeast
Yogurt/Cheese: Bacteria (Streptococcus thermophilus, Lactobacillus
bulgaricus)

3. (a) What is eco enzyme?
(b) Give two uses of eco enzyme

(a) Natural product obtained from fermentation of agricultural waste
such as fruit and vegetable waste

(b) Treats wastewater and sewage
Minimises agricultural waste such as fruit and vegetable waste
As a cleaning solution

4. (a) Figure 1 shows a type of bacterium. Name this type of bacterium
(b) Give three uses of the serum derived from the bacterium
mentioned in question 4(a)

(a) Lactobacillus sp.
(b) • Eliminates foul odour

• Facilitates animal digestion
• Produces enzyme
• Treats sewage
• Makes compost
• Advances the fishing industry

Prevention and Treatment of
Diseases Caused by Microorganisms

Prepared by: Nurulkamilah binti Khairir

1.3.1 Explain the concept of the statement ‘prevention is
better than cure’ for diseases caused by
microorganisms

1.3.2 Explain the aseptic techniques to control the
spreading of microorganisms

1.3.3 Conduct an experiment to study the effect of
antibiotic on bacterial growth

1.3.4 Communicate about methods of treatment of
infectious diseases

Aseptic Technique

“Prevention is better than cure”

Aseptic Techniques:
1. Sterilisation
2. Boiling
3. Use of antiseptics
4. Use of disinfectants
5. Use of radiation

Pathogen: Harmful microorganisms

1. Sterilisation

is the process of killing or eliminating microorganisms from an
object or a particular surrounding

Autoclave

Temperature
above 130oC

Kill
microorganisms
and their spores

Ultraviolet Radiation

Micron filter

Filter fine particles and
microorganisms (0.1 μm
– 10 μm) from water or

liquids

2. Boiling

MrMpoilam 2021

Temperature of 100oC
kills microorganisms on
objects such as milk
bottles, injection needles
and dental equipment