Science (English Medium) Class 12 - CBSE Question Bank Solutions for Biology

The correct surgical procedure as a contraceptive method is ______.

Diaphragms are contraceptive devices used by the females.

Choose the correct option from the statements given below:

1. They are introduced into the uterus
2. They are placed to cover the cervical region
3. They act as physical barriers for sperm entry
4. They act as spermicidal agents

Which one is correct for mammalian testis?

The net electric charge on DNA and histones is ______.

Nucleosome core is made of ______.

Barr body in mammals represents ______.

In oocyte secondary maturation occurs in ______.

Which of the following is correct about mammalian testes?

Lower narrow end of uterus is called ______.

Bartholin’s glands are situated ______.

Structure connecting the fetus to placenta is ______.

Histone proteins are ______.

The structure in chromatin seen as ‘beads-on string’ when viewed under electron microscope are called ______.

Find out the wrong statement about heterochromatin.

The external genitalia of the human female is called ______.

The opening of the vagina is often covered partially by a membrane called ______.

The finger-like projections, called fimbriae, help in the collection of ovum into the fallopian tube following ovulation.

Endometrium undergoes cyclical changes and help in uterine movements.

Mark the odd one.

Figure A shows the front view of the human female reproductive system and Figure B shows the development of a fertilized human egg cell

Figure A

Figure B

Identify the correct stage of development of the human embryo (Figure B) that takes place at the sites X, Y, and Z respectively in the human female reproductive system (Figure A).

Choose the correct option from the table below: