Q.I   Name the following :

1.  The food factories of plants.
2.  A bacteria that can fix atmospheric nitrogen.
3.  Chlorophyll containing partner in lichens.
4.  The cells that protect tiny pores on the leaves called stomata .
i) leaves                ii) Rhizobium                 iii) Alga                  iv) Guard cells

Q.II   Short answer type questions:

Q1.  What is mean by nutrition?
Ans:  The mode of taking  food by an organism and its utilization of the body is called nutrition.

Q2.  Who are autotrophs?
Ans:  Organisms that prepare their own food are called autotrophs . Example-green plants.

Q3.   Differentiate between autotrophs and heterotrophs .
    Autotrophs                                                       Heterotrophs
i)  Organisms that prepare their                      i)  Organisms that depend on
own food.                                                              others for their food are
ii)  Eg: green plants                                            ii)  Eg: human beings .

Q4.   What is the function of chlorophyll?
Ans:  Chlorophyll helps to capture the energy of the sunlight which is needed for the synthesis of food.

Q5.   Why are algae green in colour?
Ans:  Algae contains chlorophyll which gives them the green colour.

Q6.   Give some examples of leguminous plants.
Ans:  Gram, peas, moong, pulses, beans etc.

Q7.   How do fungi derive nutrition?
Ans:  Fungi secrete digestive juices on the dead and decaying matter and convert it into a solutions. They then absorb the nutrients from it.

Q8.   How do plants fulfill their need of nitrogen?
Ans:  Soil has certain bacteria that convert gaseous nitrogen into a usable form and release it into soil. These are then absorbed by the plants along with water.

Q.III    Give reasons for the following:

1)   Plants cannot use nitrogen present in the soil directly.
Ans:  Plants can use nitrogen only in soluble form while in soil nitrogen is present in inorganic form.

2)   Farmers timely spread manure or fertilizers in the fields.
Ans:  Plants absorb minerals nutrients from the soil and so their amount in the soil keep on declining. Fertilizers and manures contains plant nutrients that enrich the soil.

3)   Farmers do not add nitrogen fertilizers to the leguminous plants.
Ans:  Roots of leguminous plants have a symbiotic association with a bacterium called Rhizobium. This bacteria converts atmosphere nitrogen into a soluble form and thus provides nitrogen to the plants.

Q.IV   Draw a neat labelled diagram of ‘A’ section through a leaf and label it.
a) Guard cell             b) Stoma                   c) Chlorophyll