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प्रश्न
Pollen grains are formed by _________ division in locules of anthers.
पर्याय
meiosis
mitosis
amitosis
binary
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उत्तर
Pollen grains are formed by meiosis division in locules of anthers.
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संबंधित प्रश्न
A student was asked to observe and identify the various parts of an embryo of a red kidney bean seed. He identified the parts and listed them as under:
I. Tegmen
II. Testa
III. Cotyledon
IV. Radicle
V. Plumule
The correctly identified parts among these are
(A) I, II and III
(B) II, III and IV
(C) III, IV and V
(D) I, III, IV and V
Name the parts A, B and C shown in the diagram and write their functions.
What is pollination?
A student while observing an embryo of a pea seed in the laboratory listed various parts of the embryo as given below:
Testa, Tegmen, Radicle, Plumule, Micropyle, Cotyledon.
On examining the list the teacher remarked that only three parts are correct. Select three correct parts from the above list:
(a) Testa, Radicle, Cotyleddon
(b) Tegmen, Radicle, Micropyle
(c) Cotyledon, Plumule, Testa
(d) Radicle, Cotyledon, Plumule
Name the parts A, B and C shown in the following diagram and state one function of each.
How does the process of fertilisation take place in flowers?
The reproductive part of a plant is the ______.
State the name of the functional unit concerned with sexual reproduction.
Where is the female gamete formed in flowering plants?
Fill in the following blank with suitable word :
The ovule becomes a .......... after fertilisation.
Draw a neat sketch of the stamen of a flower. Mark in it filament and anther.
Explain the terms 'self pollination'
Name the part of a seed which grows into root.
In tobacco plant, the male gametes have 24 chromosomes.
What is the number of chromosomes in the female gamete?
In tobacco plant, the male gametes have 24 chromosomes.
What is the number of chromosomes in the zygote?
When an insect sits on the flower of a plant then some particles A present in the top of little stalks in the flower attach to its body hair. When this insect now sits on the flower of another similar plant, then particles A attached to the hair of insect are put on the top of a flask-shaped organ at the centre of flower. The particle A grows a long tube b from the top of flask-shaped organ through which C moves down and reaches the bottom part of flask-shaped organ. Here C fuses with the nucleus of d contained in structure E. the fusion of C and D forms a new cell f which grows and develops into a seed of the plant.
(a) What are particles A? What is the process of transferring A from one flower to another flower of similar plant by the insect known as?
(b) What is the name of tube B?
(c) What is C which moves down through the tube B?
(d) Name D and E.
(e) What is F?
In a bisexual flower, inspite of the young stamens being removed artificially, the flower produces fruit. Explain.
Put a tick mark (✓) against the correct alternative in the following statement
Reproductive whorls of a flower are:
Fill in the blank by selecting suitable word:
A flower bearing only male or female parts is known as __________ flower.
Fill in the blanks:
A stamen consists of ______ and ________.
State whether the following statement is true (T) or false (F):
Stamens make egg cells.
The students of a class were asked by the teacher to study the different parts of an embryo of an angiosperm. Given below are the essential steps for the experiment :
A. Soak the seeds in plain water and keep them overnight.
B. Cut open the soaked seed and observe its different parts.
C. Take some healthy seeds in a petri-dish.
D. Drain the excess water, cover the seeds with a wet cotton cloth and leave them as it is for a day.
The correct sequence of these steps is
(a) C, A, D, B
(b) C, D, A, B
(c) A, C, D, B
(d) A, C, B, D
Explain the process of fertilisation in flowers.
(a) Identify A, B and C in the given diagram and write their functions.
(b) Mention the role of gamete and zygote in sexually reproducing organisms.
“Cell division is a type of reproduction in unicellular organism.” Justify.
Draw a diagram of the longitudinal section of a flower and label the following parts.
Answer the following question.
List two agents of pollination?
Find the odd one out:
Accessory whorls : Calyx and corolla : : essential whorls : ______________
Gloriosa superba exhibits ______.
Pineapple fruit develops from ______.
Length of pollen tube depends on the distance between ______
Give reason for the following:
Fertilization cannot take place in flowers if pollination does not occur.
Is the chromosome number of zygote, embryonal cells and adult of a particular organism always constant? How is the constancy maintained in these three stages?
Where is the zygote located in the flower after fertilization?
The figure below shows the concept of double fertilization. Complete the flow chart showing the progress at each step:
In flowering plants, the pollen grains are transferred to stigma by pollination but the female germ cells are present in the ovary.
Explain with the help of a labelled diagram (only concerned parts), how the male germ cell reaches the ovary.
Explain the post fertilization changes that occur in the ovary of a flower.
In male reproductive whorl of a flower the archesporial cells are formed by ______.
