Page 147 - KOMPILASI ARAHAN TUGASAN PEKA SPM KINTA UTARA 2022

CONTOH JAWAPAN PELAJAR
1.1.3 EKSPERIMEN UNTUK MENGKAJI FAKTOR YANG MEMPENGARUHI PERTUMBUHAN
MIKROORGANISMA (NILAI pH)
1.1.3 EFFECT OF pH TO THE GROWTH OF MICROORGANISMS.

Aim : To study the effect of pH value on the growth of Bacillus sp. (K1P1)

Problem statement: What is the effect of pH value on the growth of Bacillus sp.? (K1P2)

Hypothesis: The growth of Bacillus sp. Is most rapid at pH 7. (K1P3)

Variables: (K1P4)
Manipulated variable: pH value
PANITIA SAINS DAERAH KINTA UTARA
Responding variable: number of colonies of Bacillus sp.
Constant variable: volume of Bacillus sp. Culture solution

Apparatus and Materials: Bacillus sp. Culture solution, sterile nutrient agar, dilute hydrochloric acid,
dilute sodium hydroxide solution, distilled water, cellophane tape, petri dishes (K1P5)

Procedure: (K1P6)
1. The arrangement of apparatus is set up as shown in the diagram.
2. Petri dishes J, K and L are covered and the lids are taped with cellophane tape.
3. Petri dishes J, K and L are inverted and kept in a dark cupboard for three days.
4. The number of bacterial colonies in each Petri dish at the end of the experiment is observed and
recorded.

(K1P7)
Observation: (K3P1)
Petri dish pH value Number of bacterial colonies
J 7
K Less than 7
L More than 7
(K3P2)

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