Question

Crop and gizzard are characteristic features of
A) Balaenoptera
B) Draco
C) Hippocampus
D) Struthio

Answer 1

Hint: Crop and Gizzard is defined as a thick-walled muscular organ that has functions similar to the human stomach. It is also observed in birds. It is composed of structures which mainly helps in increasing the surface area of the food so that enzymes can act efficiently.

Complete answer:
The gizzard is defined as an oval, muscular, and thick-walled structural organs. It is composed of six chitinous ridges on which teeth like structures are present which help in grinding and churning of the food. It is used to convert the food into a fine semisolid state. The gizzard is a modified structure found in different insects depending upon requirements.

Now let us find solution from given options:
A) Balaenoptera : It belongs to whales. They possess teeth for the grinding of food and do not possess crops or gizzard.
B) Draco : It belongs to the genus of lizards and is also said as the flying lizard. They are kind of arboreal insectivores.
C) Hippocampus : It is a kind of fish that belongs to bony fish. It is also called a seahorse. They show the presence of a complete digestive system.
D) Struthio : This belongs to the kingdom Aves. These are specialised to show the presence of crops and gizzard and help in grinding and crushing of food.

Hence the correct answer is option ‘D’ i.e Struthio.

Note:The main function that is performed by the gizzard and crop is grinding the food and not storage. Food is stored in the crop which is the structure present just before the gizzard in the digestive system of insects. Also, the structure of chitinous plates varies in the gizzards of different insects.