planttttsssss.pptx atomospheric plants in the

plants

1. FUNCTIONS OF A LEAF continued PHOTOSYNTHESIS: Photosynthesis is defined as the process which helps leaves prepare food for the plant with the help of carbon-di-oxide and water in the presence of sunlight and a green pigment (in leaves) called chlorophyll . The food prepared is stored in various parts of the plant in the form of starch . ACTIVITY : In order to see if leaves really do perform photosynthesis, let us take a leaf and immerse it in a test tube filled with spirit. Place this test tube in a beaker filled with water ; then heat the beaker. After the leaf loses its colour, wash it and pour iodine solution over it. We can see that it turns blue-black in colour; this shows the presence of starch. AUDITI DEY/6/SCI/ONLINE/2020 1

2. ROOTS The root is a very important component of the plant system for the simple reason that in its absence, the plant ceases to exist. Roots generally grow under the ground. AUDITI DEY/6/SCI/ONLINE/2020 2

3. TYPES OF ROOTS There are two major types of roots which exist in plants. TAP ROOTS: In this type of root system, there is a prominent and long root and a bunch of smaller roots which grow from this main root called lateral roots . Plants showing reticulate venation in leaves have tap roots . AUDITI DEY/6/SCI/ONLINE/2020 3 CORIANDER RADISH

4. TYPES OF ROOTS continued FIBROUS ROOTS : In this type of root system, a group of similar-sized roots emerge from the base of the plant. They do not have a main root . Plants showing parallel venation in leaves have fibrous roots . AUDITI DEY/6/SCI/ONLINE/2020 4 GRASS RICE (PADDY) WHEAT

5. FUNCTIONS OF ROOTS Roots are responsible for absorbing minerals and water from the soil and transferring them to the stem. Another important function of roots is to firmly anchor the plant in the ground. This is essential to support the upright position of the plants . AUDITI DEY/6/SCI/ONLINE/2020 5

6. FUNCTIONS OF ROOTS continued Roots also perform the function of storing important nutrients and food for growth. There are some roots which are edible. AUDITI DEY/6/SCI/ONLINE/2020 6 CARROTS BEET ROOT RADISH TURNIP

7. FLOWERS Flowers are the colourful , seed- bearing parts of a plant which grow at the end of the stem . They are the reproductive part of a plant. AUDITI DEY/6/SCI/ONLINE/2020 7 HIBISCUS ROSE PETUNIA LILY DAHLIA CHRYSANTHEMUM

8. PARTS OF A FLOWER A flower typically consists of the following parts : RECEPTACLE : It is the base of a flower to which all the parts of a flower are attached. AUDITI DEY/6/SCI/ONLINE/2020 8

9. PARTS OF A FLOWER AUDITI DEY/6/SCI/ONLINE/2020 9

10. PARTS OF A FLOWER continued SEPALS : They are the green leaf-like parts in the outermost circle of a flower. All sepals taken together are called Calyx . They protect the flower during its bud stage . Some flowers have jointed sepals, while some have separate sepals. AUDITI DEY/6/SCI/ONLINE/2020 10 JOINTED SEPALS OF DATURA SEPARATE SEPALS OF ROSE

11. PARTS OF A FLOWER continued PETALS : These are colourful , together known as corolla, and are present inside the sepals. They attract insects for pollination and protect the reproductive organs of the flower . S ome flowers have jointed petals and some others have separate petals. AUDITI DEY/6/SCI/ONLINE/2020 11 JOINTED PETALS SEPARATE PETALS

12. PARTS OF A FLOWER continued STAMEN : I t is the male reproductive part . It consists of anther and filament. The anther is a sac-like structure that produces and stores pollen . The filament supports the anther . AUDITI DEY/6/SCI/ONLINE/2020 12

13. PARTS OF A FLOWER continued PISTIL/CARPEL : I t is the female reproductive part . It is comprised of three parts- stigma, style and ovary. Stigma is the top-most part of a carpel. It is sticky and receives pollen during pollination. The style is the long tube which connects the stigma to the ovary . The ovary contains a lot of ovules. AUDITI DEY/6/SCI/ONLINE/2020 13

14. BRAIN TEASERS Do all flowers have sepals, petals, stamens and pistils? Are there flowers that do not have one or more of these? Are there flowers which have parts other than these? Do all flowers have the same number of sepals, petals, stamens and pistils? Are the number of sepals and petals in a flower always the same? AUDITI DEY/6/SCI/ONLINE/2020 14

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