CHAPTER 6
A MCQ
1
(a) Endosperm
(b) Exalbuminous
(c) Aleurone grain
(d) Coleoptile
2. (d)
B
1. TRUE OR FALSE
(a)False
(b)True
(c)False
(d)True
2. NAME
(a) Maize
(b) Alkaline pyrogallic acid
(c) Part of the embryonic axis between the point of attachment of cotyledon & plumule_ Epicotyl ( Make correction in the text book)
(d) Rhizophora
(e) Aleurone layer
(f) Plumule with folded leaves- Seedling( Change the question)
3. FILL IN THE BLANKS
(a) Radicle, above
(b) Coleorhiza, coleoptile
(c) Testa, tegmen
(d) Micropyle
(e) Stored food(endosperm)
4.
(a) 1st male gamete, micropyle, egg cell, zygote, embryo
(b) Allogamy, fusion of gamete, zygote, embryo, seed
(c ) Seed coat bursts, radicle grows downward, hypocotyl elongates, hypocotyl forms a loop above the soil, epicotyl elongates
C SHORT ANSWER
1. What is the difference between an embryo and a seed?
Seed is the ripened ovule. It contains embryo which develops in to a new plant. Embryo has developed from zygote. Zygote in turn has developed by the union of male & female gamete.
2. Endospermic seed- Poppy seeds, Palm seeds
Non-endospermic- Pea, orchid
3. During the germination of seeds the water absorbed enable the enzymatic activities or chemical reactions which in turn convert the food stored in the cotyledon or endosperm into diffusible form. This makes the absorption of nutrients easier.
4. We won’t say maize fruit or maize seed though it’s a fruit. Its known as maize grain. Here, fruit wall and seed coat are fused together to form a protective layer. Therefore, we call such fruit as grain.
D. LONG ANSWER
1. (a) Seed coat protects delicate inner parts from injury and from the attack of bacteria, fungi& insects
(b) Seeds absorbs water through micropyle& Diffusion of respiratory gases takes place through micropyle.
(c ) Cotyledons contain food for the growing embryo.
(d ) Radicle develops into root (e) Plumule develops into shoot
2 Page 50: Experiment no2
3 Germination is the process of formation of a seedling developed from the embryo. In potato vegetative propagation method involves the sprouting of the bud which is present in the axillary position. Eye of potato or axillary bud which is present in the underground stem of potato tuber sprouts to become a new plant. We can call it as germination, since it involves the development of new plant.
4. DIFFERENCES
(a) Epigeal and hypogeal germination- If the epicotyl elongates, the cotyledons remain underground(or on the ground if the seed is just on the ground) and the germination is then called hypogeal. If the hypocotyl elongates the cotyledons are pushed above the ground and this type of germination is called epigeal germination
(a) Coleorhiza & coleoptile- The radicle towards the pointed end is enclosed by a protective sheath is called coleorhiza. The plumule towards the upper broader side of embryonic region is enclosed by a protective sheath is called coleoptile.
(b) Bean Seed & maize grain- Bean seed is a dicotyledonous seed whereas maize grain is a monocotyledonous fruit formed by the fusion of fruit wall & seed coat fused together to form a protective layer.
5 Differences between germination & vivipary
Germination is the process of formation of seedling developed from embryo. Germination takes place after the dormancy period of a seed, which is certain period after the ripening & dispersal of fruit. As the seed gets favourable conditions like O2, H2O & temperature
6 Yes. One seeded fruit we can find in type of fruit known as ‘drupe’ eg: mango. In the case of maize, fruit wall is fused with seed coat to give protection for growing embryo. It is single seeded fruit only. This type of fruit is ‘caryopsis’. Eg: rice grain, maize grain
7. In epigeal germination, hypocotyl elongates the cotyledons are pushed above the ground. This enable the seedling to grow full swing into a plant.
8.
(a) Seeds absorb water through micropyle. Diffusion of respiratory gases for the growing embryo takes place through micropyle.
(b) Embyo
(c) Endosperm
(d) Refer page:48 ( Structure of Bean seed)
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