SCIENCE F5 CHAPTER 1B ppt

3. Antiseptic

is a chemical substance that can be applied on human skin or wounds to
prevent pathogenic infections
Example: acriflavine (yellow medicine), povidone and 70% isopropyl alcohol (IPA)

Acriflavine and povidone: Kill microorganisms
Proflavine: block or prevents the growth of microorganisms
70% of isopropyl alcohol: Act as antiseptic and sterilizing agent

4. Disinfectant

is a chemical substance used on non-
living things
Example: bleach, hydrogen peroxide,
liquid chlorine

Do not use on skin or wound!

5. Radiation These rays can penetrate into
microorganisms cells and destroy them
Ionising radiation: UV ray, X-
ray, gamma ray

Antibiotics

Experiment 1.3

Page 37 Science Form 5 KSSM Text Book











Methods of Treating Infectious Diseases

Pneumonia Shingles

Athlete’s foot



Formative Practice 1.3 (page 41)

1. State five examples of aseptic techniques used to control the
spread of pathogens

Sterilisation, boiling, using antiseptic, disinfecting, radiation

2. How is the aseptic technique related to the phrase ‘prevention is
better than cure’?

The aseptic technique is applied to protect a person from infections
by eliminating existing or nearby pathogens before the person
contracts any diseases caused by the pathogens.

3. (a) What is sterilisation?
(b) How is sterilisation carried out?
(c) Why is the use of autoclave more effective in the prevention
of microorganisms compared to boiling water?

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

(b) Sterilisation is carried out using heat, chemical substances,
radiation, high pressure and filtration.

(c) The temperature in the autoclave (121°C – 132°C) can kill
microorganisms and their spores. Water boiled at 100°C can only kill
microorganisms but not their spores. This is because their spores
can withstand a temperature of 100°C.

4. State one similarity and one difference between antiseptics and
disinfectants

Similarity: Both antiseptics and disinfectants can be used to kill
pathogens.

Difference: Antiseptics can be applied on the skin of humans but
disinfectants are not suitable to be applied on the human
skin.

5. Name three examples of ionising radiation used in the aseptic
technique

Ultraviolet ray, X-ray, gamma ray

6. State the type of substance that is used to treat the following

infectious diseases:
(a) athlete’s foot (a) Athlete’s foot: antifungal

(b) pneumonia (b) Pneumonia: antibiotic

(c) shingles (c) Shingles: antiviral

Summative Practice 1

Page 43 Science Form 5 KSSM Text Book

























THANK YOU

Prepared by: Pn. Nurulkamilah binti Khairir

MrMpoilam 2021