Structure of Dicot Embryo

Q. What would be the number of chromosomes of the aleurone cells of a plant with 42 chromosomes in its root tip cells ?Steps.

Q. (a) When a seed of an orange is squeezed, many embryos, instead of one are observed. Explain how it is possible.

(b) Are these embryos genetically similar or different? Comment. [5]

Q. Within the embryo sac, three cells at chalazal end are called

1. Egg apparatus
2. Central cells
3. Synergids
4. Antipodal cells

Q. Differentiate between:

Q. In the embryos of a typical dicot and a grass, true homologous structures are

1. Coleorhiza, Coleoptile
2. Coleoptile, Scutellum
3. Cotyledons, Scutellum
4. Hypocotyl, radicle

Q. Draw a neat and labelled diagram of a mature embryo sac. [3 marks]

Q.

In bryophytes, the sporophytic phase is represented by

1. egg

2. spore mother cell

3. antheridium

4. spores

Q. How many antipodal cells are present in an embryo sac?

Q. Choose the correct statement

1. One pollen mother cell produces 2 male gametes where as one megaspore mother cell produces only 1 female gamete.
2. Megaspore mother cell differentiates from sporogenous tissue.
3. Three free nuclear divisions occur in megaspore to form embryo sac.
4. Female gametophyte in angiosperms is 8 celled and 7 nucleated

Q. Differentiate between Coleoptile and coleorhiza

Q. Answer in brief:
Describe the stages in embryo development in a dicot plant.

Q.

What happens after fertilization in hilum part and antipodal cell in embryo sac?

Q. In which family $\left(9\right)+1$ androecium condition is found?

1. Malvaceae
2. Papilionaceae
3. Solanaceae
4. Poaceae

Q. Assertion: In a dicotyledonous embryo, the portion of embryonal axis above the level of cotyledons is the epicotyl and the portion below the level of cotyledons is hypocotyl.

Reason: The epicotyl terminates with radicle or root tip and hypocotyl terminates with plumule or shoot tip.

1. Both assertion and reason are true and reason is the correct explanation of assertion.
2. Both assertion and reason are true but reason is not the correct explanation of assertion.
3. The assertion is true but reason is false.
4. Both assertion and reason are false.

Q. In embryogeny of dicot plants, the suspensor cell undergoes transverse divisions forming suspensor which is :

1. 16 -21 celled
2. 6 -10 celled
3. 11 -15 celled
4. 1 -5 celled

Q. The radicle in dicots is covered at the tip by__________.

1. root cap
2. coleoptile
3. coleorrhiza
4. none of the above

Q. Assertion :In mosey inflorescence, the main axis ends in a flower, but the lateral axis show continuous growth Reason: The arrangement of flower in this inflorescence is centrifugal.

1. If both the assertion and the reason are true and the reason is a correct explanation of the assertion
2. If both the assertion and reason are true but the reason is not a correct explanation of the assertion
3. If the assertion is true but the reason is false
4. If both the assertion and reason are false

Q. If the number of chromosomes in endosperm of a dicot plant is 36, the root cells will contain

1. 24 chromosomes
2. 72 chromosomes
3. 28 chromosomes
4. 48 chromosomes

Q.

1. Orchids
2. Utricularia
3. Orobanche
4. All the above

Q.

During the embryogeny in Capsella bursa-pestoris

(A) Embryo does not show distinction of plumule, cotyledons and radical

(B) The cotyledons are made by hypobasal tier

(C) The vesicular cell is towards the micropylar region

(D) Most of the radicle is made by hypophysis

Q. Select the correct diagram.

1. 
2. 
3. 
4. 

Q.

1. hypocotyl
2. epicotyl
3. plumule
4. choleorhiza

Q. The number of synergids and antipodals present in a typical angiosperm embryosac at maturity respectively are

1. Two and three
2. One and two
3. One and three
4. Three and two

Q. Epiblast present in certain monocot embryo represents.

1. Rudimentary leaves
2. Mesocotyl
3. Scutellum
4. Second cotyledon

Q. Starting with the zygote, draw the diagrams of the different stages of embryo development in a dicot.

Q.

The embryo sac in most angiosperms is made up of

1. 8 cells.

2. many cells.

3. 7 cells and 8 nuclei.

4. 7 cells and 7 nuclei.

Q. In the embryos of a typical dicot and grass, true homologous structures are?

1. Colerrhiza and coleoptile
2. Coleoptile and scutellum
3. Cotyledons and scutellum
4. Hypocotyl and radicle

Q. The part of embryo axis between plumule and cotyledonary node is

1. Hypocotyl
   
2. Cotyledons and radicle
3. Epicotyl and hypocotyl
4. Epicotyl
   

Q. Terminus of epicotyl is called

1. Coleorhiza
2. Radicle
3. Plumule
4. Coleoptile

Q. A typical dicotyledonous embryo consists of

1. Radicle only
2. Radicle, embryonal axis and cotyledons
3. Cotyledons only
4. Embryo axis only