Question

If an unfertilized egg of a frog is pricked by a minute needle
A. It will remain alive but undivided.
B. It will change into a young one soon.
C. It will begin to divide.
D. It will die.

Answer 1

Hint: Artificial parthenogenesis can be defined as a process in which an unfertilized egg of an animal developed into an embryo and then to a mature animal without fertilization by sperm. The process is initiated by an artificial stimulation like pricking with a needle, mechanical damage, cooling, etc. The word parthenogenesis came from a Greek word which means virgin birth.

Complete answer: There is a fine difference between parthenogenesis and parthenocarpy. The former is an asexual process of reproduction where an embryo is formed without fertilization by sperm. The latter can be defined as the seedless fruit formation process. If an unfertilized egg of a frog is pricked with a minute needle, cell division starts immediately and artificial parthenogenesis will take place.
Artificial parthenogenesis of unfertilized eggs can also be stimulated by keeping the unfertilized egg in temperature changes, or keeping it in solutions of seawater, or keeping it in dilute acid solutions.

So, the correct answer is option C. It will begin to divide.

Note: Parthenogenesis is also seen in the case of plants and referred to as apomixes or apogamy. Parthenogenesis is seen in invertebrate animals including nematodes, scorpions, bees, etc. in the case of vertebrates, it is seen in fishes, amphibians, reptiles. It is very rarely seen in birds also.