BIO201 Lab Manual

Contents

S. No.

Practical

P. No.

Study of Eukaryotic Cell Study Plant cell Study Animal cell Cell structure in Staminal hair of tradescantia Study of different types of plastids Study of cellular reproduction Study of Mitosis (Prepared slides) Study of Mitosis (Prepared slides) Mitosis: smear/squash preparation of onion roots A microscope (from the Ancient Greek: μικρός, mikrós, small and σκοπεῖν, skopeîn, to look or see) is an instrument used to see objects that are too small to be seen by the naked eye. Microscopy is the science of investigating small objects and structures using such an instrument. Microorganisms are so small that they cannot be seen by naked eye. The optical instrument that magnifies the image of these organisms and enables us to view their morphological features is a microscope. Antony van Leeuwenhoek is often considered as the father of microscopy. Most bacteria measure in the range of 0.5 to 4 µm. Mycoplasma and Coxiella are the shortest among bacteria and Spirochetes the longest. Viruses are ultramicroscopic structures; they can’t be seen by compound microscopes. They can be visualized by electron microscopes and their measurements are in nm (nanometer).

Various types of microscopes are

There are several different types of microscopes used in light microscopy, and the four most popular types are Compound, Stereo, Digital and the Pocket or handheld microscopes. Some types are best suited for biological applications, where others are best for classroom or personal hobby use. Simple microscope Compound microscope Dark ground microscope Phase contrast microscope Fluorescent microscope Interference microscope Electron microscope Atomic Force microscope Polarization microscope Fig 1.1: Detail of Microscope

A microscope is commonly used in a microbiological study of organisms. The basic modern microscope found in schools, hospitals, and research centers is a compound microscope which has a series of lenses to collect and focus the light transmitted through the specimen. The various parts of a microscope with their associated function are mentioned below.

Tube:

Tube or the body tube, connects the eyepiece to the objective lenses.

Eyepiece or ocular lens:

Eyepiece is the lens, present at the top and is used to see the objects under study. Eyepiece lens contains a magnification of 10X or 15X.

Resolving nosepiece:

It is also known as the Turret. Resolving nosepiece has holders for the different objective lenses.