Page 92 - Science Class 08

of eyes, shape of hands and texture of hair and v Golgi complex are flat baggy stacks placed
some other characters. in parallel posi ons one on the other.

Nucleoli are round bodies found in certain v Lysosomes are small round bodies having
regions of chromosomes, though some cells enzymes to break down harmful bacteria.
may not have them. These nucleoli help the v Plas ds are there in plant-cells only, not in
forma on of ribosomes-cell’s protein-producing animal cells. They contain pigments. Green
centres. They are made of protein and RNA plas ds are called chloroplasts that are
(ribonucleic acid). RNA and DNA are chemically found in the leaves of green plants. They
similar. aid them to synthesise food. Tomatoes are

CYTOPLASM (kytos = hollow + plasma = liquid) red due to plas ds with red pigment.
The cytoplasm is the substance that fills the It must be remembered that basically cells are

cell. It is found inside the cell membrane, similar in structure, yet they a ain different
surrounding the nucleus and the cell organelles. looks in different organs and body-parts. The
It is a jelly-like substance. The cytoplasm is 80% cells in leaves, stem and roots of a plant differ
water and is clear in colour. Although the in appearance. Similarly, cells in the stomach,
cytoplasm is 80% water, it is more like a thick liver and kidneys of an animal are different.
jelly than a watery substance, but when you
shake or s r it liquefies more. The cytoplasm Xylem Phloem
contains dissolved nutrients and helps to
Xylem
dissolve waste. The nucleus floats with the
cytoplasm changing its shape as it moves.

Each organelles does a par cular job as follows: Phloem
Root Stem
v Vocuoles are membrane–enclosed empty

spaces inside the cytoplasm. Plants have
larger vocuoles than animals.
v Mitochondria are organelles rod-shaped or
round. They generate energy for the cell.

ATP Synthase par cles Xylem
Vascular Bundle Phloem
Inner membrane space
Leaf
Matrix Liver
Gallbladder
Ribosome
Cristae
Granules

Inner membrane
Sphincter Stomach
DNA Outer membrane of oddi
Pancreas
Mitochondria Liver

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