MICROBIOLOGY AND PARASITOLOGY Laboratory Lab Lesson 1

Bacteriological Sterilizers a) Autoclave is a large pressure cooker type device on which the boiling temperature

of water is increased by an increase in pressure. b) Oven is used in dry sterilization. Glassware and other inert objects are sterilized in this fashion.

c) Cellulose membrane filters prevent the passage of all bacteria and larger microorganisms of fluid passing through them. The microfiltration set-up includes a membrane filter funnel, suction flask, rubber tube and suction pump.

Inoculating Loop and Needle

These devices are consist of a needle to which is attached a piece of wire made of some inert metal such as nichrome or platinum. Inoculating loops and needles are often used for purpose of transferring microbial growth from one container to another without introducing contaminants. The wire is sterilized by flaming to red heat then allowed to cool for about 10-15 seconds.

Alcohol Lamp

A lamp fueled with denatured alcohol use in sterilizing inoculating loops and needles through direct flaming. Combustion of alcohol produces clean blue flame.

Bacteriological Slides

Several types of slides are used in microbiology. The plain glass slide is the most common type of slide used in making temporary and permanent microbial smears. The concave slide has a hollowed-out portion in the center. The slide is used for observing living microorganisms. Growing a micro culture of fungi uses deep well slide. The entire upper surface is frosted and the depression is cylindrical rather than concave.

ACTIVITY

Objective

At the end of the exercise the student must be able to identify the common apparatus and equipment used in microbiology laboratory and state their functions or uses.

Materials

test tubes of various designs

indicators

petri dish

buffers

pipettes

incubator

autoclave

oven

membrane filter set-up

slides of various types

alcohol lamp

Procedure

1. Examine the different apparatus/equipment as describe earlier. apparatus/equipment.

Draw each

2. Familiarize the functions/uses of the different equipment.