Question

Number of chambers in cockroach heart is
A) 4
B) 10
C) 13
D) 15

Answer 1

Heart is the most important organ and it is responsible for pumping blood throughout the body. The human heart is divided into four chambers.

Complete answer:
The blood vascular system of cockroaches contains a tubular heart, a blood vessel known as anterior aorta and a system of ill-defined blood spaces or sinuses. The blood vessels of cockroaches are poorly developed.

Option A: The human heart is divided into 4 chambers and not cockroaches. Therefore, this is the incorrect option.
Option B: Body cavity of cockroach is known as hemocoel as it remains filled with hemolymph (blood). The heart is present along the mid-dorsal line of the body. The heart of a cockroach is an elongated muscular tube. It consists of 13 segmentally arranged funnel-shaped chambers. Therefore, this is the correct option.
Option C and D: As the heart of cockroach is made up of 13 chambers, therefore these are the incorrect options.

Thus, the correct answer is option (B) 13.

Note: The heart of cockroach consists of thirteen chembers. The last two posterior chambers are very small and they are separated from one another with ostia on either side. Blood from the sinuses enters the heart through ostia and is pumped back anteriorly to sinuses again.