Answer the following questions :
Q1. Paheli wants to know why our body cannot make food from carbon dioxide, water and minerals like plant do.
Ans: As our body does not have chlorophyll, we cannot make food like the plants do.
Q2. Boojho wants to know how water and minerals absorbed by roots reach the leaves.
Ans: Water and minerals are transported to the leaves by the vessels which run like pipes throughout the roots, stems and leaves. These vessels are xylem and phloem which form a continuous path for the nutrients to reach the leaves.
Q3. Paheli wants to know what is so special about the leaves that they can synthesis food but other parts of the plant cannot.
Ans: Leaves can synthesis food because it contains a green pigment called chlorophyll.
Q4. Boojho has observed some plants with deep red, violet or brown leaves. He wants to know whether these leaves also carry out
photosynthesis.
Ans: Yes. Such leaves also have chlorophyll but the large amount of red, brown or violet colour masks the green colour.
Q5. Paheli wants to know whether mosquitoes, bed bugs , lice and leeches that suck our blood are also parasites?
Ans: Yes, these insects are parasites as they harm the host while they suck their blood.
Q6. Bhoojo is confused. If the pitcher plant is green and carries out photosynthesis, then why does it feed on insects?
Ans: Pitcher plant grows in soil which lacks nitrogen, therefore they eat insects to fulfill their need of nitrogen.
Q7. Boojho wants to know how these organisms acquire nutrients. They do not have mouths like animals do. They are not like green plants as they lack chlorophyll and cannot make food by photosynthesis.
Ans: These organisms called fungi derive nutrition from dead and decaying matter.
Q8. Paheli is keen to know whether her beautiful shoes, which she wore on special occasions, were spoiled by fungi during the rainy season. She wants to know how fungi appear suddenly during the rainy season.
Ans: The fungal spores are generally present in the air. When they land on wet and warm things they germinate and grow.
Q9. Boojho says once his grandfather told him that his wheat fields were spoilt by a fungus. He wants to know if fungi cause diseases also.
Ans: Yes. Fungi causes many diseases like skin diseases, intestinal infections etc
TEXTUAL EXERCISE (END TEXT)
Q.1 Why do organisms need to take food?
Ans: Organisms need to take food to:
i) Build their body to grow .
ii) To repair damaged parts of the body .
iii) Get energy to carry out life processes .
Q.2 Distinguish between a parasite and a saprotroph.
Ans:
Parasite Saprotroph
i) Derive nutrition from the i) Derive nutrition from dead
body of other living organisms. and decaying matter.
ii) Eg: Cuscuta ii) Eg: Fungi
Q.3 How would you test the presence of starch in leaves?
Ans: Iodine solution on contact with starch gives a blue black colour. So we can check the presence of starch by putting iodine on the leaves.
Q.4 Give a brief description of the process of synthesis of food in green plants.
Ans: Green plants prepare their food by a process called photosynthesis. In this process, a green pigment in the leaves called chlorophyll helps to capture the energy of the sunlight. This energy is used to prepare food from carbon dioxide and water. It can be represented by an equation.
Carbon dioxide + Water + Chlorophyll Sunlight Carbohydrates + Oxygen.
Q.5 Show with the help of a sketch that the plant are the ultimate source of the food.
Ans: (Grass) (Grasshopper ) (Frog ) (Snake) (Eagle)
Q.6 Fill in the blanks:
a) Green plant are called ______ since they synthesis their own food.
b) The food synthesized by the plants is stored as ________ .
c) In photosynthesis solar energy is captured by the pigment called ________ .
d) During photosynthesis plant take is ________ and release ________ .
Ans:
a) Autotrophs b) Starch c) Chlorophyll d) Carbon dioxide, oxygen.
Q.7 Name the following :
1) A parasite plant with yellow, slender and tubular stem .
Ans: Cuscuta
2) A plant that has both autotrophic and heterotrophic mode of nutritions.
Ans: Pitcher plant
3) The pores through which leaves exchange gases.
Ans: Stomata .
Q.8 Tick the correct answer:
a) A marbel is an example of :
i) autotroph ii) parasite √ iii) saprotroph iv) host
b) The plant which traps and feeds on insects is :
i) cuscuta ii) china rose iii) pitcher plant √ iv) rose
Ans:
a) ii) b) iii)
Q.9 Match the items given in column I with those in column II :
Column I Column II
i) Chlorophyll a) Bacteria
ii) Nitrogen b) Heterotrophs
iii) A marbel c) Pitcher plant
iv) Animals d) Leaf
v) Insects e) Parasite
Ans:
i) d ii) a iii) e iv) b v) c .
Q.10 Mark “T” if the statements is true and “F” if it is false:
i) Carbon dioxide is released during photosynthesis.
ii) Plants which synthesis their food themselves are called saprotrophs.
iii) The product of photosynthesis is not a protein
iv) Solar energy is converted into chemical energy during photosynthesis.
Ans:
i) F ii) F iii) T iv) T .
Q.11 Choose the correct options from the following:
1) Which part of the plant get carbon dioxide from the air for photosynthesis:
i) Root hair ii) Stomata iii) Leaf veins iv) Sepals
2) Plant take carbon dioxide from the atmosphere mainly through their:
i) Roots ii) Stem iii) Flowers iv) Leaves
Ans:
1) ii) 2) iv) Leaves