Test: Asexual Reproduction

• Hydra reproduces by asexual mode of reproduction. It reproduces by budding.
• Budding is a type of asexual reproduction which does not involve the fusion of gametes.
• A new organism develops from an outgrowth or bud due to cell division at one particular site. The bud remains attached to the parent plant and separates after it gets mature. It leaves a scar at the point of separation.
• The newly developed organism is a clone to its parent cell. 

Grafting is the process of joining two plants together and are grown as one. Such a plant has two portions - one upper and the other lower. The upper portion of the plant is known as the scion, which is grafted on to the lower portion known as the rootstock.

• In cauliflower, the part which is eaten as vegetable is the inflorescence which is a head or capitulum, and consists of a tightly packed aggregation of undeveloped white or creamy flower buds borne on the thick hypertrophied branches of the much branched inflorescence.
• The short stout stem of cauliflower bear this large condensed, compact, swollen, hemispherical head at the top, surrounded by large leaves.

There is no natural death in single celled organisms like Amoeba and bacteria because parental body is distributed among the offspring. In such organisms, reproduction occurs by cell division where a cell (parent) divides into two halves and each rapidly grows into an adult (offspring). 

A method known as multiple fission is adopted by the unicellular organism amoeba to survive and reproduce under unfavourable conditions.
When the conditions are unfavourable, Amoeba withdraws its pseudopodia and becomes almost round.

Budding: Hydra reproduce asexually through budding, where a bud forms that develops into an adult and breaks away from the main body.

Vegetative propagation is a form of asexual reproduction of a plant. Only one plant is involved and the offspring is the result of one parent. The new plant is genetically identical to the parent.

Therefore, Option C is correct

A) In potato, banana, and ginger, the plantlets arise from nodes present in the modified stem. Tubers of potato are the underground modification of stem which stores starch. It has buds on the nodes which helps in the growth of new plant as these buds are meristematic in nature. The buds are also known as eye. Ginger is propagated by the rhizome. It is a underground stem modification. The terminal bud of rhizome may or may not grow into an aerial shoot. The stem is differentiated into nodes and internodes. Adventitious root occurs on the lower side. The plantlets arise from nodes present in the modified stem. Banana is propagated by inflorescence. The female flowers of the inflorescence present on the node of the true stem matures and develop into fruit without fertilization of gametes. So, the statement is false.

B) Water hyacinth is an aquatic weed which is popularly known as the terror of Bengal because it grows very rapidly and eliminates the growth of several species and even eliminates them. Due to its voluminous growth in water bodies, it increases the biological oxygen demand of the water and leads to the death of aquatic life which also cause a major decrease in the biodiversity due to alien species invasion. The statement is true.

C) Asexually developed plants are the clone of their own parents because of the fusion of gametes does not take place in vegetative propagation so there is no chance of recombination and variation. The parent cell divides to form daughter cell by mitosis due to which the offspring are genetically identical to the parent. The statement is true.

D) A zoospore is a motile asexual spore that uses a flagellum for locomotion. The statement is true.

So, the correct answer is option A.

The vegetative propagation in mint (Mentha arvensis) occurs by sucker. Sucker is a non-green underground specialized stem developing from the underground base of an erect shoot or crown.

• The embryo gets nourishment inside the mother body through a special tissue called placenta.
• The embryo grows inside the mother's womb and gets nourishment from mother's blood through the tissue called placenta.
• The placenta is a temporary organ that develops in the uterus during pregnancy. It attaches the fetus to the uterine wall. It also provides nutrients to the fetus and also allows the fetus to transfer waste product's to the mother's blood.