Page 81 - Science Class 06

Organisms Average life span We cannot see them with naked eyes. They
can be seen through microscope.
Bacteria 20 minutes
Mul cellular organisms, made up of many
Housefly 1-4 months cells, also differ in shapes and sizes. They

Squirrel 8-9 years have organs of different shapes and sizes.

Dog 15-18 years Many mul cellular organisms are very small
Lion 20-25 years such as insects, spider, rabbits, squirrel, etc.
Some organisms are small such as dogs,
Horse 25-30 years
goats, cats, etc. Some mul cellular organ-
Man 60-80 years
isms are big such as cows, horses, camels,
Elephant 70-90 years etc. But some mul cellular organisms are
Tortoise 120-150 years very big such as elephant, whale, etc.

Like animals, plants also differ in shapes and
sizes. Some plants are small and weak called
herbs. Shrubs are small to medium sized

Viruses are neither living nor non-living plants. Trees are very big and strong plants.
organisms, but when they enter the body Species
of a living organism, they grow and You come across various kinds of organisms
mul ply. in your surroundings. Are they all alike?
Certainly not. A dog differs from a cat, a cat

from a pig and a pig from a goat. Each kind
of organism (dog, cat, pig and goat) has
1. Name any two mul cellular organisms. many individuals which are similar to each

2. Name the parts of plants that can other. These individuals may differ slightly
reproduce. but their form, habit and behaviour are
3. What do the plants need for almost the same. Such a group of similar
photosynthesis? living organisms is known as a species .

4. Name the plants that response to The members of a species have similar body
s muli.
parts, live in the same habitat, eat the same
kind of food and reproduce among
ARE ALL LIVING THINGS SIMILAR?
themselves. A horse will always produce
You should know that all living beings
horses. It cannot produce an elephant.
possess some common characteris cs.
A rose plant always produce seeds from
However, the way they carry on different
which only rose plants can grow.
life processes are different. Besides, living
organisms differ in shapes and sizes. Some There are about 16,00,000 species of
organims are made up of a single cell called animals and 4,00,000 species of plants in

unicellular organisms like bacteria, hydra the world.
amoeba, etc. They are very small organisms.

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