Question

state the caustic microorganisms
and modes of transmission & human disease of Chickenpox​

Answer 1

Answer:

Y

ou have seen several kinds of

plants and animals. However,

there are other living organisms

around us which we normally cannot

see. These are called microorganisms

or microbes. For example, you might

have observed that during the rainy

season moist bread gets spoilt and its

surface gets covered with greyish white

patches. Observe these patches through

a magnifying glass. You will see tiny,

black rounded structures. Do you know

what these structures are and where do

these come from?

2.1 Microorganisms

Activity 2.1

Collect some moist soil from the

field in a beaker and add water to

it. After the soil particles have

settled down, observe a drop of

water from the beaker under a

microscope. What do you see ?

Activity 2.2

Take a few drops of water from a

pond. Spread on a glass slide and

observe through a microscope.

Do you find tiny organisms moving

around?

These observations show that water

and soil are full of tiny organisms,

though not all of them fall into the

category of microbes. These

microorganisms or microbes are so

small in size that they cannot be seen

with the unaided eye. Some of these,

such as the fungus that grows on bread,

can be seen with a magnifying glass.

Others cannot be seen without the help

of a microscope. That is why these are

called microorganisms or microbes.

Microorganisms are classified into

four major groups. These groups are

bacteria, fungi, protozoa and some

algae. Some of these common

microorganisms are shown in

Figs. 2.1 - 2.4.

Viruses are also microscopic. They,

however, reproduce only inside the cells

of the host organism, which may be a

bacterium, plant or animal. Some of the

viruses are shown in Fig. 2.5. Common

ailments like cold, influenza (flu) and

most coughs are caused by viruses.

Serious diseases like polio and chicken

pox are also caused by viruses.

Diseases like dysentery and malaria

are caused by protozoa(protozoans)

whereas typhoid and tuberculosis (TB)

are bacterial diseases.

You have learnt about some of

these microorganisms in Classes VI

Explanation: