KNOWLEDGE IS POWER

Search This Blog

March 20, 2020

Get link
Facebook
X
Pinterest
Email
Other Apps

What is biology?
Study of life

Get link
Facebook
X
Pinterest
Email
Other Apps

Comments

Special types of microscopes

Source: Wikipedia Dark ground microscope: It is also called dark field illumination microscope. There are certain microorganisms, which are very difficult to stain example spirochetes. To visualize them under microscope dark field illumination is used. The microorganism appears bright against a dark background. It is similar to dust particle seen in a beam of light from a ventilator in a dark room. In this microscope a special condenser with a central black area is placed just behind the objective. A dark ground, phase contrast microscope can be made from an ordinary microscope. For this, cut out a thick talc sheet of the size of a filter. Colour the central two third with black ink. Place it along the filter in the holder below the condenser Fluorescent microscope: Certain dyes have the characteristic of glowing when exposed to ultraviolet light. In fluorescent microscope the object is stained with these (fluorochrome) dyes. The light source of microscope is replaced with the source t...

Immunity:Non specific defense: Introduction

IMMUNITY: Immunity is the ability of body to resist any change from foreign particle and the harmful chemical release by them IMMUNOLOGY: "The science which deals with study of immune system,working mechanism,disorders etc" OR "Immunology is the study of foreign partice that cause damage to the living body and defence mechanism taken by the body to eleminate them" Father of immunolgy is EMIL VON BEHRING(He discovered antibody) NON-SPECIFIC DEFENSE: It is generalzed responce of body which is similar for most of the infection. In this antibodies not involved mean it fight with pathogens without antibodies. It is present from birth. It is also known as INNATE immunity It consist of 1-External defence(First line of defence) 2-Internal defence(Second line of defence) External defence prevent the pathogen from entering into the blood. When pathogen enter into the blood then i...

HUMAN SKULL - AN OVERVIEW

HUMAN SKULL: The bones of the skull are grouped into two different catagories 1-Cranial bones 2-facial bones Cranial bones are 8 and facial bones are 14 in number. Cranial bones form the cranial cavity which encloses and protect the brain CRANIAL BONES 1-Frontal bone 2-Parietal bones 2 3-Occipetal bone 4-Temporal bones 5-Sphenoid bone 6- Ethmoid bone FRONTAL BONE: It forms the forehead. It is single. It is common to cranial and facial bones but we include it in cranial bones. In a child there is right and left frontal bones which are join togeather by suture. At the age of 6 these two equal bones join to form a single bone PARIETAL BONE: The two parietal bones form the roof of the cranial cavity. They are largest TEMPORAL BONES: The two parietal bones present at ear region. Temporal bone consist of EXTERNAL ACOUSTIC MEATUS(ear opening). OCCIPETAL BONE: It forms base and back of the cranium. There is large aparture present in it called foramen magnum( Through...

Powered by Blogger

Comments

Post a Comment