1. The following statements compare the process of oogenesis & spermatogenesis. Which one is not true? (1)
a. Production of ovum ceases at certain ages, but sperm production continues even in old men.
b. Oogenesis begins in the embryonic stages, but spermatogenesis starts at the onset of puberty.
c. Meiotic arrest occurs both in oogenesis and spermatogenesis.
d. Polar bodies are formed in oogenesis.
2. The diagram represents a process of gametogenesis. Closely observe it and answer the following.
a. Is it spermatogenesis or oogenesis?
b. What the smaller shaded circle represent?
c. Write down two significance of production of the same. (Score: ½ + ½ + ( ½ x2=2)
1. “Though one ovum is produced from a primary oocyte it can result into a male or female child after fertilization. But in the case of spermatocytes though 4 sperms are produced only two of them can result into a female child after fertilization.” Justify. (1)
1. Observe the diagram and answer the questions: (3)
a. Identify A and B
b. What is the function of C?
c. In which of the marked part reduction division takes place? What is the significance of it?
1. Diagram of mammalian sperm is given. Label the marked parts. (1)
1. (1) In which part of the human reproductive system the following events occur? (2)
a. Fertilization b. Implantation
(2) Diagram of a human blastocyst is given below. Identify A & B.
1. Schematic representation of gametogenesis is given below. Identify A. Write one difference between A & B. (2)
2. Mother’s milk is considered essential for new born infants.
a. Name the fluid secreted by mother from breast during the initial days of lactation.
b. What type of immunity it provides? (1)
1. Choose the odd one from the following and write the common features of others. (1)
a. Estrogen b. Androgen
c. Relaxin d. Progesterone
2. Complete the flowchart showing spermatogenesis by filling A and B and answer the questions.
A → Primary spermatocyte → Secondary spermatocytes → B → Spermatozoa
a. What is the chromosome number of primary spermatocytes?
b. What is the significance of reduction division in spermatogenesis? (2)