Page 96 - APS(2022)_TG5 _Edisi Guru

Sains Tingkatan 5 Bab 1
Tarikh:

EKSPERIMEN Kesan pH terhadap Pertumbuhan Mikroorganisma 1
Wajib 1.6 Effect of pH on the Growth of Microorganisms
Pendekatan inkuiri
BAB
PEKA
Tujuan Mengkaji kesan pH terhadap pertumbuhan bakteria.
Aim To study the effect of pH on the growth of bacteria. K1P1

Pernyataan Bagaimanakah pH mempengaruhi pertumbuhan bakteria?
Masalah How does pH affect the growth of bacteria?
Problem Statement

Hipotesis Bakteria tumbuh subur dalam keadaan neutral tetapi tidak dalam keadaan EKSPERIMEN WAJIB
Hypothesis
berasid atau beralkali .
Bacteria grow well in neutral condition but not in acidic or alkaline
conditions. K1P2

pH bubur nutrien
Pemboleh Ubah (a) Dimanipulasikan :
Variables pH of nutrient broth
Manipulated
Kekeruhan bubur nutrien
(b) Bergerak balas :
Responding The cloudiness of the nutrient broth

(c) Dimalarkan : Kuantiti bakteria / Jenis bakteria
Constant Quantity of bacteria / Type of bacteria K1P3

Bahan Bubur nutrien steril, kultur bakteria (Bacillus subtilis), asid hidroklorik cair, natrium hidroksida
Materials cair dan air suling.
Sterile nutrient broth, bacterial culture (Bacillus subtilis), dilute hydrochloric acid, dilute sodium hydroxide and distilled
water.

Radas Tabung uji, picagari steril 1 cm , kapas steril dan rak tabung uji.
3
Apparatus Test tubes, sterile 1 cm syringe, sterile cotton wool and test tube rack. K1P4
3
Prosedur 1. Sediakan susunan radas seperti ditunjukkan pada rajah di bawah.
Procedure Set up the apparatus as shown in the diagram below.

K2 A B C
PI Kapas Kapas Kapas
1 Cotton wool Cotton wool Cotton wool
2 5 cm bubur nutrien 5 cm bubur nutrien 5 cm bubur nutrien
3
3
3
3 5 cm nutrient broth 5 cm nutrient broth 5 cm nutrient broth
3
3
3
4 + + +
3
3
3
S 1 cm kultur bakteria 1 cm kultur bakteria 1 cm kultur bakteria
3
3
3
1 cm bacterial culture 1 cm bacterial culture 1 cm bacterial culture
+ + +
asid / acid alkali / alkali air suling / distilled water
3
3
2. Tuang 5 cm bubur nutrien steril dan 1 cm kultur bakteria ke dalam tabung uji yang berlabel
A, B dan C.
Pour 5 cm of the sterile nutrient broth and 1 cm of the bacterial culture into test tubes labelled A, B and C.
3
3
3. Tambahkan beberapa titis asid hidroklorik cair, natrium hidroksida cair dan air suling
masing-masing ke dalam tabung uji A, B dan C.
Add a few drops of dilute hydrochloric acid, dilute sodium hydroxide and distilled water into test tube A, B and C
respectively.
4. Sumbat mulut setiap tabung uji dengan kapas steril.
Stuff the opening of each test tube with sterile cotton wool.
5. Biarkan semua tabung uji selama dua hari.
Leave all the test tubes for two days.
6. Catatkan pemerhatian anda selepas dua hari.
Record your observations after two days.
15 © Penerbitan Pelangi Sdn. Bhd.

01 BAB 1.indd 15 7/28/21 2:56 PM