Page 56 - Genius Kidz Prudence Learning Sc-8

In a human body, the smallest cells are of
blood and the longest cells are the nerve
-6
cells. Living RBC is of 9 mm (9x10 m) and a
nerve cell or a neuron is more than 1 meter
long.

Xylem cell
(b) Sizes : Smallest cell is of bacteria,

Mycoplasma gallisepticum. Its size is 0.1
–6
mm (10 m). Ostrich egg cell is the largest
cell and is about 170mm in length and 7 cm
in diameter.
My plasma gallisepticum cell Ostrich Egg cell
Activity 2

Think about it… we are mutlicellular so we can respire, show digestion, excrete…. and do a variety of other
functions supporting life. But do unicellular organisms are able to manage all these functions of life? If yes,
how??
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Difference between plant cell and animal cell :

Plant cell Animal cell
! It is surrounded by a cell wall, in ! It has only cell membrane, cell wall

addition to the cell membrane. is absent.
! It has chlorophyll present in the ! Chloroplast are absent.
organelles called chloroplasts.

! It usually has one or two large ! Vacuoles are either absent or are
vacuoles. very small in size.

Cell division and growth growth of a cell is limited. After reaching a

When a cell is formed it is small in size. After certain size is divides to form two cells. The
digesting food it grows in size. However, the new cells formed are known as daughter cells
while the process is known as cell division.

An individual blood cell takes about 60 second to make a complete circuit of the body.

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