For artificial hybridisation experiment in bisexual flower, which of the sequences is correct?
(1) Bagging → Emasculation → Cross pollination → Rebagging
(2) Emasculation → Bagging → Cross pollination → Rebagging
(3) Cross pollination → Bagging → Emasculation → Rebagging
(4) Self-pollination → Bagging → Emasculation → Rebagging
Which of the following is false?
I. Endosperm formation starts prior to first division of zygote
II. Angiospermic endosperm is mostly 3N while gymnospermic one is N.
III. The most common type of endosperm is nuclear.
IV. Coconut has both liquid nuclear (multinucleate) and cellular endosperm.
V. Milky water of green tender coconut is liquid female gametophyte.
(1) I and II only
(2) III only
(3) V only
(4) II only
Diagram given below shows stages in embryogenesis in a typical dicot (Capsella). Identify structures A to D respectively:
1. Suspensor, Radicle, Plumule, Cotyledons
2. Hypophysis, Radicle, Plumule, Cotyledons
3. Suspensor, Plumule, Radicle, Cotyledons
4. Suspensor, Radicule, Plumule, Hypocotyls
Go through the given diagram of a typical dicot embryo. In which of the following all the 3 parts labelled as A, B, C with their respective functions are correctly identified?
A | B | C | |
1. | Plumule, shoot system formation |
Radicle, root system formation |
Hypophysis, formation of radicle |
2. | Plumule, shoot system formation |
Radicle, root system formation |
Cotyledon, food storage |
3. | Radicle, root system formation |
Plumule, shoot system formation |
Cotyledon, food storage |
4. | Radicle, root system formation |
Plumule, shoot system formation |
Endosperm, food storage |
Which of the following is not correct?
(1) As the seed matures, its water content is reduced and seeds become relatively dry(10-15% moisture by mass)
(2) The seed dormancy is the internal or innate inhibition of generation of normal or viable seeds
(3) Embryo in dormant seed shows higher rate of general metabolic rate
(4) Because of dormancy seeds remain viable for longer period and can be stored
Which of the following statements is false?
1. | Some 2000 years old viable seeds of Pheonix dactylifera were discovered during archaeological excavation of King Herod's palace near Dead Sea |
2. | Record of 10,000 years of dormancy of seeds has been estimated in Lupinus arcticus |
3. | The number of seeds in each fruit in case of orchid and some parasitic forms like Orobanche and Striga is one |
4. | Many fruits have evolved mechanisms for dispersal of seeds |
Hybrid seeds have to be produced every year because:
(1) Hybrid plants become sterile in coming years
(2) They show more heterosis in coming years
(3) Hybrid vigour is not maintained beyond one generation as segregation of genes begins in the second generation
(4) Hybrid seed industry tends to increase cost of the seeds
Active research is going on in many laboratories around the world to understand the genetics of apomixis. What is the purpose of such active research?
(1) Hybrid plants are directly formed by apomixis
(2) Apomixis is the method to produce seed without fertilization
(3) To transfer apomictic genes into hybrid varieties which will prevent loss of hybrid vigour with successive years
(4) Apomixis produces genetically different individuals
Both, autogamy and geitonogamy are prevented in:
(1) Papaya
(2) Cucumber
(3) Castor
(4) Maize
A typical angiosperm anther is bilobed with each lobe having two theca i.e. dithecous. Theca is separated often by :
1. A longitudinal groove running lengthwise.
2. A longitudinal groove running breadth wise.
3. A transverse groove running breadth wise.
4. A transverse groove running lengthwise.