Polyembryony

Q.

What is the ploidy of the embryo sac?

Q. From the following options, identify the reason why the hybrid seeds have to be prepared every year

1. Seed industry tends to increase the cost of seeds every year
2. Hybrid plants turn sterile in the coming years
3. Seeds show more heterosis in the coming year
4. Hybrid vigour may not be maintained in more than one generation

Q. Assertion: A diverse germplasm collection is a very important prerequisite for plant breeding.

Reason: Genetic variability is the root of plant breeding programme.

1. Both assertion and reason are correct and the reason correctly explains assertion
2. Both assertion and reason are correct but the reason is not the correct explanation for assertion
3. Assertion is correct but reason is incorrect
4. Both the assertion and reason are incorrect

Q.

Choose the option that correctly identifies the given statements as true or false.

I. Spontaneous polyembryony includes the examples of plants that exhibit naturally occurring polyembryony

II. True polyembryony refers to embryos’ development in more than one embryo sac in the same ovule as in Fragaria.

III. Polyembryony is common in groundnuts and oranges.

1. I-True, II- False, III- True
2. I-False, II- False, III- True
3. I-True, II- False, III- False
4. I-True, II- True, III- True

Q. Nucellar polyembryony is reported in the species of___________.

1. Citrus
2. Gossypium
3. Triticum
4. Brassica

Q. The plant part which consists of two generations one within the other, is

1. Seed
2. Embryo
3. Germinated pollen grain
4. Unfertilized ovule

Q. Polyploidy is characterized by

1. presence of two sets of chromosomes
2. absence of a copy of chromosome
3. presence of more than two sets of chromosomes
4. presence of a single set of chromosomes

Q.

To meet the demands of society, the production of a large number of plantlets in a short duration practised in the floriculture and horticulture industry is called

1. Hybridoma technology

2. Somaclonal variation

3. Somatic hybridisation

4. Micropropagation

Q. What would be the genetic nature of apomictic embryos?

1. Genetically dis-similar
2. Genetically similar
3. Sometimes genetically similar and sometimes genetically dis-similar
4. Always haploid

Q. Normally one embryo develops in one seed but when an orange seed is squeezed many embryos of different shapes and sizes are seen. Mention how it has happened.

Q. The statement 'The stages of development for an animal embryo are the same as other animals' adult stages" was given by

Q.

Conversion of ammonia to urea is done by ________ cycle?

1. ornithine

2. citrulline

3. arginine

4. fumeric

Q. Best example of polyembryony is .................

1. Mango
2. Citrus
3. Capsicum
4. Cocos

Q.

What are good classes of seed?

Q. (a) Explain the different ways apomictic seeds can develop. Give an example of each.
(b) Mention one advantage of apomictic seeds to farmers.
(c) Draw a labelled mature stage of a dicotyledonous embryo.

Q. Consider the following fruit crops.
a. Musa
b. Malus
c. Citrus
d. Mangifera
In which of the nuclear polyembryony is known to occur commonly?

1. $1,2$ and $3$
2. $3$ only
3. $3$ and $4$
4. $1,2$ and $4$

Q. Which one is a gametophytic polyembryony?

1. Adventitive polyembryony
2. Antipodal polyembryony
3. Nucellar polyembryony
4. Endosperm polyembryony

Q. Two mark Questions:
Suggest two advantages to a farmer for using apomictic seeds of hybrid varieties.

Q. What are disadvantages of vegetative propagation

Q. A collection of plants and seeds having all possible alleles of all the genes of a particular crop is called

1. genomic library
2. genome
3. germplasm collection
4. herbarium

Q. Formation of additional embryo from part of the same embryo or embryo sac is

1. True polyembryony
2. Adventitive polyembryony
3. False polyembryony
4. Haploid-diploid polyembryony

Q. Polyembryony/ adventitive polyembryony occurs in

1. Carthamus
2. Citrus
3. Corchorus
4. Maize

Q. Adventive embryony in Citrus is due to

1. Integuments
2. Nucellus
3. Zygotic embryo
4. Fertilised egg

Q.

What do you mean by parthenocarpy? Give an example.

Q. Molybednum takes key role in

1. Nitrate reduction
2. Translocation of solutes
3. Tryptophan Synthesis
4. Synthesis of ascorbic acid

Q. Which is agamospermy?

1. Grafting
2. Adventive embryony
3. Layering
4. All the above

Q. The polyembryony commonly occurs in.

1. Tomato
2. Potato
3. Citrus
4. Turmeric

Q. Formation of embryo directly from nucellus and integument is

1. Adventitive polyembryony
2. Apospory
3. Apogamy
4. Apomixis.

Q.

1. Vegetative propagation
2. Amphimixis
3. Agamospermy
4. Parthenogamy

Q. Formation of an extra embryo from nucellus or integument is

1. Simple polyembryony
2. Adventive polyembryony
3. Vegetative polyembryony
4. Cleavage polyembryony