Please answer these questions as per class 9th and answering 1 question would also be a great help.
1)describe prokaryotic cell
2)describe eukaryotic cell
3)Differentiate between a plant cell and an animal cell.
4)Write a short note on vacuoles.
5)How are mitochondria important for the cell?
6)Describe the chemical composition of cell wall.
7)Name the functional segment of DNA.
8)List two similarities between mitochondria and plastids.
9)Give the functions of following organelles of the cell:
(a) Chloroplast (b) Nucleus (c) Leucoplast (d) Chromoplast
10)Write the names of two cell organelles that have their own DNA and ribosomes.
11)What is endocytosis? Name an organism that feeds by this method.
12)State cell theory. Name the scientist who presented it.

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2015-06-17T13:12:59+05:30

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1. The Cells of some most primitive organisms that are blue - green algae , bacteria etc. which lack nuclear membrane around their genetic material and hence are called Prokaryotic cells.

2. The cells of other organisms possess true nucleus bounded by nuclear membrane. Such organisms are called Eukaryoric Organism.Ex- Fungi,protists etc.

4. Short Note on vacuoles ⇒ The Vacuoles occur in most cells.They are small in size but more in animal cells.

Structure  :-- Vacuoles are storage sacs for solid or liquid contents bounded by a unit membrane. In animal cells , large number of small - sized vacuoles are present.

Function :-- 1. They are storage sacs of the cell. The stored material may be solid or liquid form.
2. In some Unicellular organisms, specialized vacuoles maintain water balance of the body , so called Osmoregulation.
3.In plants, they provide turgidity and rigidity to the cells.

5. Mitochondria are the main seat of cell respiration.They use molecular Oxygen and bring about stepwise oxidation of food stuffs present in the cells to carbon- dixoide and water.Oxidation of food releases energy which is temporarily stored to form High- Energy ATP Molecules.ATP is used to bring about energy - requiring activities of the cell.On this Account , the mitochondria are often called "power houses" of the cell and ATP is called as ''energy currency of the cell'' ,In this way Mitochondria is Important to the cell.

6. The chemical composition of cell wall of plant cell is CELLULOSE.
It is structural carbohydrate and it is a sugar complex.

7.Genes are the functional segment of DNA. They carry genetic informations to parents to offspring.

8.Two Similarities.
1.They both contain their own DNA and Ribosomes.
2.They both are self replicating.

9.Chloroplast.- The convert light energy into Sugar molecules.
   Nucleus.- Controls the Activities of the cell.
   Leucoplast - They synthesis fatty acids 
   Chromoplast. - Impart various colours to Flower to attract insect for pollination  and to the fruits for alluring certain animals for seed dispersal.

10. Mitochondria and Plastids.

11.Endocytosis is the process by which animals engulf food and other organism from the external medium by plasma membrane.
Ex- Amoeba

12. Cell Theory was presented by Schleiden and Schwann. 
According to this " All plants and animals are composed of cells and cells are the basic unit of life.

3 . " THIRD ANSWER IS IN THE ATTACHMENT "
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