Define the term pollination. Differentiate between self-pollination and cross-pollination. What is the significance of pollination?

Pollination is the process of transferring pollen grains from the anther to the female part that is stigma of the same or different flower. Characteristics Self-pollination Cross-pollination Definition It is the transfer of pollen grains from the anther to the stigma of the same flower or another flower borne on the same plant. It is the transfer of pollen grains from the anther of one flower to the stigma of another flower borne on a different plant of the same species. Agents External agent not required. External agents like wind, water, insects, etc, are always required. Significance of pollination are listed below: Pollination is required for fertilization and zygote formation. Pollination helps in the production of seeds and fruits which ensures the continuity of plant species. Cross-pollination helps in the production of variation in species. Pollination is a pre-requisite for fertilization in flowering plants.

After examining a prepared slide under the high power of a compound microscope, a student concludes that the given slide shows the various stages of binary fission in a unicellular organism. Write two observations on the basis of which such a conclusion may be drawn.

Unicellular organism: Unicellular organisms are made up of only one cell. They carry out all the functions needed by the organism. Some examples of unicellular organisms are Amoeba , bacteria, etc. Binary fission: Binary fission, asexual reproduction by a separation of the body into two new bodies. The two observation that was taken by the student that concludes that the given slide shows the various stages of binary fission of a unicellular organism are as follows: Karyokinesis: In this process, the nucleus of the parent cell divides into two daughter nuclei. Cytokinesis: It is the process by which the cytoplasm of the parent cell, divides into two daughter cells.

List in proper sequence four steps of obtaining germinating dicot seeds.

A seed is formed by the fertilized ovule and pollen egg. It contains reserve food and a protective coat. When the seed is sown in the soil a new plant appears from the embryo. Dicot seed: The seed having two cotyledons is called a dicot seed. For example; gram and bean seed. The four steps for germinating dicot seeds are as follows: Imbibition: Dry seeds absorb water during the imbibition process. This results in swelling and softening of the seed coat. Respiration: In the absence of oxygen, anaerobic respiration occurs. Respiration provides energy to the seed for metabolic activity. Effect of Light: Light is important for germination as it initiates the metabolic activities inside the seed. Mobilization of reserve food: The mobilization of seed storage proteins upon seed imbibition and germination is a crucial process in the establishment of seedling. This provides essential energy to fuel growth until the seedling becomes photoautotrophic.

What is carpel? Write the function of its various parts.

Carpel is the ovule-bearing female reproductive organ in plants. Stigma, style, and ovary are three parts of a carpel. The functions are as follows: Stigma : It is the top portion of a carpel. It is the site of pollination. Pollination is the process of transfer of pollen grains from anther to the stigma. Style : It is a long, tubular structure that connects the stigma to the ovary. Ovary : It is a basal part that contains ovules that produce the seeds.

A student is viewing under a microscope a permanent slide showing various stages of asexual reproduction by budding in yeast. Draw diagrams of what he observes.

The most common method of reproduction in yeast is asexual reproduction by budding, where a small bud is formed on the parent cell. The nucleus of the parent cell splits into a daughter nuclei and migrates into the daughter cell.

Write the function of the following part in the human female reproductive system: Uterus

A uterus is a part of the female reproductive system. It is also called the womb. The functions are as follows: It receive and nurture the growing embryo. It nourishes the growing embryo (it is richly supplied with blood).

Write the function of the following part in the human female reproductive system: Oviduct

The functions of oviduct (fallopian tube) are as follows: It is the pathway through which the mature egg passes from the ovary to the uterine cavity. It is a site of fertilisation (it is a process of fusion of sperms and eggs).

Write the function of the following part in the human female reproductive system. Ovary

Ovaries are the main female sex organs. They produce female gametes. It measures about 2 to 4 cm in length. The functions are as follows: They produce one egg every month. They are also responsible for the production of sex hormones such as oestrogen and progesterone.

E M B I B E

EMBIBE CHAPTER WISE PREVIOUS YEAR PAPERS FOR SCIENCE>Chapter 8 - How do Organisms Reproduce?>CBSE-2022 (Delhi Term II - II)>Q 21

EASY

10th CBSE

IMPORTANT

Earn 100

In the following figure showing a germinating gram seed, name the parts labelled as A, B, and C.

Why is part 'B' considered to be important during germination?

Important Questions on How do Organisms Reproduce?

MEDIUM

10th CBSE

IMPORTANT

EMBIBE CHAPTER WISE PREVIOUS YEAR PAPERS FOR SCIENCE>Chapter 8 - How do Organisms Reproduce?>CBSE-2022 (Delhi Term II - III)>Q 22

State one drawback of oral contraceptive pills.

MEDIUM

10th CBSE

IMPORTANT

EMBIBE CHAPTER WISE PREVIOUS YEAR PAPERS FOR SCIENCE>Chapter 8 - How do Organisms Reproduce?>CBSE-2022 (Delhi Term II - III)>Q 23

State one drawback of Copper-T.

EASY

10th CBSE

IMPORTANT

EMBIBE CHAPTER WISE PREVIOUS YEAR PAPERS FOR SCIENCE>Chapter 8 - How do Organisms Reproduce?>CBSE-2022 (Delhi Term II - III)>Q 24

Under which category of contraceptive methods, is the use of condoms kept? In what way, is its use better as compared to other methods of contraception?

EASY

10th CBSE

IMPORTANT

EMBIBE CHAPTER WISE PREVIOUS YEAR PAPERS FOR SCIENCE>Chapter 8 - How do Organisms Reproduce?>CBSE-2022 (Outside Delhi Term II - I)>Q 25

Mention the functions of the placenta in the human female reproductive system.

EASY

10th CBSE

IMPORTANT

EMBIBE CHAPTER WISE PREVIOUS YEAR PAPERS FOR SCIENCE>Chapter 8 - How do Organisms Reproduce?>CBSE-2022 (Outside Delhi Term II - I)>Q 26

Mention the functions of fallopian tubes in the human female reproductive system.

EASY

10th CBSE