Assignment -- IX
Matter in our surrounding
Fundamental unit of life
1 List two ways to liquefy gases.
2 Give reason : (a) Water droplets appear on the outer surface of a
tumbler containing ice cold water.
(b) People prefer to wear cotton clothes in summer.
(c) On a hot sunny day people sprinkle water on the roof or open
ground.
3 Explain your observation in the following with reason involved in the
process.
(a) Salt is applied to raw mango pieces
(b) Dried raisins are kept in water for a few hours.
4 Define the following properties of matter – (i) rigidity (ii) diffusion
(iii) compressibility
(b) Arrange solids, liquids and gases in the ascending order as regards
the extent to which each of the above properties is exhibited them
(c) Write any one example from your daily life experience which is
based on diffusion of gases.
5 Why is the rate of diffusion of gases is faster in gases ?
6 How does spreading of wet clothes quickens their drying ? Explain.
7 Name the process in which diffusion takes place through a selective
permeable membrane.
8 Preetha was observing live cells of Onion in the Biology laboratory
and she observed cell wall, cytoplasm and nucleus clearly. Suddenly
her friend who was doing chemistry experiment spilled a few drops
of salt water on the slide. After some time Preetha observed the slide
and found some changes. (a) What would have been the change in
the live cells of onion peel after adding salt water ? (b) Name the type
of process.
9 How does temperature affect the rate of evaporation ?
10 Name the plastid which stores starch, oils and protein granules.
11 Draw diagram of 1) plant cell 2) Animal cell 3) Onion cell 4)
Prokaryotic cell
12 State two functions of vacuoles in a plant cell.
13 How can plant cells withstand much greater changes in the
surrounding medium than the animal cells ?
14 What are chromoplasts and leucoplasts ? Give an example of
chromoplasts which has green pigment.
15 What is evaporation ? In the following examples state which factor is
responsible for the change in rate of evaporation and how ?
(i) Clothes dry faster on a windy day. (ii) Wet clothes dry faster on
spreading them.
16 Distinguish between
1 plant cell and animal cell 2 Prokaryotic and eukaryotic cell
3 Hypotonic, Hypertonic and Isotonic
4 Solid , liquid and gases