Class 7 Science Chapter 8 MCQ

Seeds of drumstick and maple have wing which help them to be easily carried away by wind. Various seeds and fruits have some special feature due to which they are carried away in a particular way (by wind, water or animal).

Here, all the statements are correct. Hence, your answer will be option [D].

Most of the fungi and flowerless plant (such as ferns and mosses) reproduce asexually by means of spores. The common bread mould plant which grows on a piece of stale bread is a fungus. The common bread mould plant on rhizopus fungus reproduces by the method of spore formation.

Ovules contain the female gamete or female sex cells of the plant. The ovary contains one or more ovules. Each ovule contains only one female gamete of the plant. The female gamete or female sex cells of the plant which is present inside the ovule is called egg.

Here, all the statements are correct. Hence, your answer will be option [D].

Here, all the statements are correct. Hence, your answer will be option [D].

Most plants have roots, stems and leaves. These are called the vegetative parts of a plant. After a certain period of growth, most plants bear flowers. The flowers perform the function of reproduction in plants. Flowers are the reproductive parts of a plant.

Here, all the statements are correct. Hence, your answer will be option [D].

The process in which the male gamete present in pollen grain fuses or joins with the female gamete present in ovule to form a new cell called zygote, is called fertilization. After fertilization two main things happen. As the ovule present in ovary grows to become a seed. After fertilization ovary of a flower develops and becomes a fruit (with seeds inside it). Thus, fruit is the ripened ovary of a flower.

Most plants have roots, stems and leaves. These are called the vegetative parts of a plant. After a certain period of growth, most plants bear flowers. The flowers perform the function of reproduction in plants. The process in which the male gamete present in pollen grain fuses or joins with the female gamete present in ovule to form a new cell called zygote, is called fertilization. After fertilization two main things happen. As the ovule present in ovary grows to become a seed. After fertilization ovary of a flower develops and becomes a fruit (with seeds inside it). Thus, fruit is the ripened ovary of a flower. When a seed is sown in the moist soil, it begins to grow and called germination. And in this stage, the seed coats splits (as tiny root grows) downward and (the shoot grows) upwards. The seedling grows further and ultimately forms a new plant. And after a certain period, the plant bears flowers once again.

The flowers perform the function of sexual reproduction in plant. After fertilization, the ovary grows into a fruit and seeds develop from the ovules.

An alga, spirogyra reproduce by the asexual method of reproduction called fragmentation. But yeast reproduces by budding.

In the presence of water and nutrients, algae grow and multiply rapidly by fragmentation. An alga breaks up into two or more fragments, each of which grow into new individuals. This process covers a large area in a short period of time.

Stamen is the male reproductive organ of the plant whereas stigma is the female reproductive organ of the plant.

Most plants have roots, stems and leaves. These are called the vegetative parts of a plant. After a certain period of growth, most plants bear flowers. The flowers perform the function of reproduction in plants. Flowers are the reproductive parts of a plant.

Here, all the statements are correct. Hence, your answer will be option [D].

Spore formation is an asexual method of reproduction in plants, spores are not seeds. Most of the fungi and flowerless plant (such as “ferns and mosses”) reproduce asexually by means of spores. The common “bread mould” plant which grows on a piece of stale bread is a fungus. The common bread mould plant on rhizopus fungus reproduces by the method of spore formation. An alga, reproduces by the asexual method of fragmentation.

The process in which the male gamete present in pollen grain fuses or joins with the female gamete present in ovule to form a new cell called zygote, is called fertilization. After fertilization two main things happen. As the ovule present in ovary grows to become a seed. After fertilization ovary of a flower develops and becomes a fruit (with seeds inside it). Thus, fruit is the ripened ovary of a flower.

The breaking up of the body of a plant into two or more pieces on maturing, each of which subsequently grows to form a new plant, is called fragmentation. Spirogyra is a green filamentous alga plant which is found in ponds, lakes and slow-moving streams. Spirogyra reproduces by the asexual method of reproduction called fragmentation.

Some plants reproduce themselves from leaves. The leaves of some plants developed buds on them. Such leaves having buds can be used as a structure of vegetative reproduction in plants. One example of a plant which can reproduce from its leaves is “bryophyllum”. When a mature leaf of the “bryophyllum” plant falls on the ground, they grow into a new plant.

Cutting are a means of asexual reproduction in plants. The new plant formed from a cutting is exactly similar to the parent plants. The plants like rose, money plant, grapes, sugar cane, bananas, cactus can be grown by cutting method or by using stem cutting or branch cutting. But maize or corn is a plant belonging to the family of grasses. It does not flower readily and seed production is unusual except in its native habitat. Under natural conditions, maize reproduces only by seed production.

For the male gamete to be able to combine with the female gamete, it is necessary that first the pollen grains from the anther of stamen of a flower should be carried to the stigma of pistil. The transfer of pollen grains from the anther of a stamen to the stigma of pistil is called pollination. When pollination is done by insects such as bees and butterflies, called cross-pollination.

Here, all the statements are correct. Hence, your answer will be option [D].

A seed on germination grows into a new plant and fertilization in plants can only occur after pollination (i.e. only when pollen grains have fallen on the stigma of a flower). Other statements are incorrect as a plant bearing bisexual flowers can undergo sexual reproduction itself as both male and female reproductive organs are present. Also, along with insects, wind and water are also agents of pollination.

The transfer of pollen grains from anther of a stamen to stigma of a pistil is called pollination. It can occur by two ways as self-pollination (transfer occur in same flower or another flower of same plant) and cross-pollination (transfer occurring between flowers of two separate but similar plants. Insects, water and wind are agents of pollination.