Cell Structure and Functions Part 4

Good morning boys!! 

In the last class we learnt about different cell cell organelles and their functions.

As a quick recap, see if you can answer the following questions-

1. Name the plastids present in the plant cell.
2. Name the plastid that give colour to flower and fruits.
3. What is the function of mitochondria?
4. Compare the size of vacuole present in animal with the vacuole in plant.
5. What is the role of Ribosomes?

Great if you could answer these! In case you could not ,please revisit the last blog or pages 131 of your reader.

Now, in today class we will discuss about the difference between plant and animals cell. We will also discuss different cell organism and their identifying features.

LEARNING OUTCOMES
At the end of this topic, the learners will be able to-
-name unicellular organisms
-list the identifying features of some unicellular organisms like amoeba, paramecium etc

So, let us all start

                        Difference between plant cell and animal cell

Instruction: Draw the table in your respective science copy given on page 132 of book. Draw the well labelled diagram also. Need not to colour it.

Write the difference between them also.

Plant Cell: (i) It has a rigid, non living cell wall.
(ii) It usually has one or two large vacuoles.
(iii) Plastids are present.
(iv) Centrosomes are absent.
(v) Lysosomes are absent.

Animal Cell: (i) No such cell wall is present 
(ii) Vacules are either absent or are smaller in size.
(iii) Plastids are absent.
(iv) Centrosomes are present.
(v) Lysosomes are present.

Now, let us all discuss about single celled or unicellular organisms that can perform all basic activities of life and live independently.

1. AMOEBA

It is an unicellular aquatic animal, that is irregular in shape and has body projections called pseudopodia, that help to catch its prey. Food taken in by amoeba is digested in food vacuole.

2. PARAMECIUM-

It is a slipper -shaped unicellular aquatic animal. Its body is covered with small hair - like projections called cilia that enable it to to move fast in water. It has tow nuclei- macronucleus and micronucleus. 

3. EUGLENA

It is a spindle- shaped green coloured unicellular animal. It has a long thread like flagellum at its anterior end, that helps it in movement. It takes food in through its gullet. The contractile vacuoles help absorption and excretion of water.

4. CHLAMYDOMONAS
It is a unicellular  green colour aquatic plant that has a whip-like structure called flagella that helps it to float in water. Its green colour in due to the presence of chloroplast in the cell.

5. YEAST
It is a unicellular plan( Fungi). It causes fermentation of foods containing carbohydrate.

A QUICK CHECK!

NAME THE UNICELLULAR ORGANISM WITH HELP OF THE CLUES GIVEN:
1. Has false feet called pseudopodia.
2. Has hair -like structures called cilia.
3. Is spindle -shaped.
4. It causes fermentation in foods containing carbohydrates.
5. Is a slipper-shape aquatic animal.
6. An aquatic animal with a flagellum.
HOMEWORK

1. Do question D ( page 134) in the reader itself.
2. Do questions A,B on page 135 in the reader itself
3. Do questions A,B on page 136 in the reader itself.