CLASS 8 HOLIDAY HW AND WORKSHEET.

* LEARN THE Q & A OF CELL STRUCTURE AND FUNCTION.

* PRACTICE THE DIAGRAMS.

* LEARN TWENTY ELEMENTS NAME AND THEIR SYMBOLS, SOME COMMON COMPOUNDS AND VALENCY TABLE.

* COMPLETE THE WORKSHEET.

1. A ball of dough is rolled into a flat chapatti. Name the force exerted to change the shape of the dough.

 2. Where do we apply a force while walking?

3. A girl is pushing a box towards east direction. In which direction should her friend push the box so that it moves faster in the same direction?

4. A gas filled balloon moves up. Is the upward force acting on it larger or smaller than the force of gravity?

5. Does the force of gravitation exist between two astronauts in space?

6.Read the following statements and write the appropriate term against each statement.

A. I control the functions of a cell. Who am I? ...................

 B. I am like a policeman. I do not allow anything and everything to get in and out of the cell. Who am I? ...................

 C. I transfer characters from parents to offsprings. Who am I?

7.Classify the following terms into cells, tissues and organs and write in the tabular column given below.

 RBC, WBC, Nerve cell, blood, muscle cell, blood vessels, brain, heart, hand, stomach,bone,kidney, skin.

8.Fill in the blanks with the terms given in the box below: Nucleus, chromosomes, cell wall, cell membrane, protoplasm, cytoplasm, ribosome, cell organelles

The outermost layer of plant cells is the (a)---------------- beneath which is the (b)------------------------ . The term (c)-------------------- refers to the jelly-like substance containing all the (d)--------------------------- . The (e)------------------- contains thread-like structures called (f)------------------- .(g)---------------- involved in protein synthesis.