Advertisements
Advertisements
प्रश्न
In a flowering plant a microspore mother cell produces four male gametophytes, while a megaspore mother cell forms only one female gametophyte. Explain.
Advertisements
उत्तर
Cyanobacteria are free living or symbiotic blue-green algae which are capable of converting atmospheric molecular nitrogen into soluble forms like nitrites or nitrates. They enrich the nitrogen content of the soil, thus, acting as a natural fertilizer. They replenish the soil with the nitrogenous compounds and hence are useful in agriculture.
संबंधित प्रश्न
List the three stages the annuals and biennial angiosperms have to pass through during their life cycle.
Read the statement and answer the questions that follow.
A flower of brinjal has 520 ovules in its ovary. However, it produces a fruit with only 480 viable seeds.
(a) What could have prevented the rest of the 40 ovules from maturing into viable seeds? Explain giving a reason.
(b) Describe the development of a dicot embryo in a viable seed.
(c) Why certain angiospermic seed albuminous while others are exalbuminous? Explain.
A capsicum flower has 240 ovules in its ovary. But, it produces a fruit with only 180 viable seeds.
Give a reason for the Following:
Pollen grains of wind-pollinated flowers are produced in large quantities.
Explain the events upto double fertilisation after the pollen tube enters one of the synergids in an ovule of an angiosperm.
Sketch and label ‘structure of a pea flower’.
Explain the different types of endosperms in angiosperms.
Science of cultivation, breeding, marketing and arrangement of flowers is called ______.
Fragrant flowers with well developed nectaries are an adaptation for ______.
Angiosperms have dominated the land flora primarily because of their ______.
Which of the following statement is incorrect?
The flower is a highly modified and condensed reproductive shoot specially meant for ______
Male and female reproductive structures of the angiosperms are ______.
Axile placentation is observed in ______.
What is the floral envelope called when the calyx (sepals) and corolla (petals) cannot be differentiated from one another?
The swollen terminal part of the pedicel where all the floral whorls are arranged is known as __________.
What is the main function of the corolla?
