Solved Examples on Human Reproduction

Question1: Fertilizin is a chemical substance produced from [BHU 1985; CBSE PMT 1991, 97; CPMT 1997; JIPMER 2000]

(a)   Mature eggs                 

(b)   Acrosome                     

(c)    Polar bodies                

(d)   Middle piece of sperm  

Answer: a

Solution:

Fertilizin is a sperm-agglutinating agent that is produced by an egg and plays a part in the preliminaries of fertilization

Question2: Sperms produce an enzymatic substance for dissolving egg coverings. It is called [DPMT 1986, MP PMT 1986; KCET 2001; Wardha 2001]

(a)   Hyaluronic acid

(b)   Hyaluronidase

(c)    Androgamone

(d)   Diastase

Answer: b

Solution:

When a capacitated sperm reaches the ovum, it is able to penetrate the cumulus cell layer surrounding the egg with the assistance of hyaluronidase enzymes present on the surface of the sperm.

Question3: During cleavage, what is true about cells [CBSE PMT 1991; CPMT 1999]

(a)   Nucleocytoplasmic ratio remains unchanged   

(b)   Size does not increase   

(c)    There is less consumption of oxygen             

(d)   The division is like meiosis

Answer: b

Solution:

The size of the cells does not increase during cleavage.