Science (English Medium) इयत्ता १२ - CBSE Important Questions

The following is the illustration of the sequence of ovarian events (a − i) in a human female

(i) Identify the figure that illustrates ovulation and mention the stage of oogenesis it represents.

(ii) Name the ovarian hormone and the pituitary hormone that have caused the above mentioned event.

(iii) Explain the changes that occur in the uterus simultaneously in anticipation.

(iv) Write the difference between ‘c’ and ‘h’.

(v) Draw a labeled sketch of the structure of a human ovum prior to fertilization.

During the reproductive cycle of a human female, when, where and how does a placenta develop? What is the function of placenta during pregnancy and embryo development?

Describe the changes that occur in ovaries and uterus in human female during the reproductive cycle.

Explain the development of a secondary oocyte (ovum)  in a human female from the embryonic stage upto its ovulation. Name the hormones involved in this process.

Why are the human testes located outside the abdominal cavity? Name the pouch in which they are present.

Write the location and functions of the following in human testes :

Leydig cells

Draw a labelled diagram of the female reproductive system.

Name the function of the following:

Corpus luteum

Name the functions - Acrosome of sperm.

Where in the fallopian tube does fertilization occur in humans?

Describe the development of a fertilized ovum upto implantation.

Why is follicular phase in the menstrual cycle also referred as proliferative phase? Explain.

Explain the events that occur in a graafian follicle at the time of ovulation and thereafter.

State the Function of Chorionic Villi

Explain the ovarian and uterine events that occur during a menstrual cycle in a human female under the influence of pituitary and ovarian hormones respectively.

Differentiate between vas deferens and vasa efferentia.

Differentiate between spermatogenesis and spermiogenesis.

Explain the changes that occur in the ovary and uterus during menstrual cycle in human females. Mention the influence of pituitary and ovarian hormones in bringing these changes.

Draw a sectional view of the human ovary. Label the following parts :

In the figure given below, parts A and B show the level of hormones which influence the menstrual cycle. Study the figure and answer the questions that follow:

1. Name the organs which secrete the hormones represented in parts A and B.
2. State the impact of the hormones in part B on the uterus of the human female during 6 to 15 days of the menstrual cycle.