Question

The chambers in heart of fish are:
A. 1 ventricle and 1 auricle
B. 1 ventricle and 2 auricle
C. 2 ventricle and 2 auricles
D. 2 ventricles and 1 auricle

Answer 1

Hint: The single circulatory system found in the fishes. The blood pumps into gills then passes to the other body parts. The systematic heart contains four chambers: the sinus venosus, atrium, ventricle, and conusor bulbus. The valves maintain the unidirectional flow of the blood.

Complete answer:
-The heart is the important organ of vertebrates. It carries deoxygenated blood and after purification from lungs transports it to other parts of the body.
-The blood flows in a single circuit in fishes. Fishes have a single circulation type. It has two chambers that have only a single atrium and a single ventricle. The blood from all the body parts collects into the atrium and the ventricles. The atrium collects the deoxygenated blood in a single atrium and pumps it out through a ventricle. The blood leaves out through the gills and immediately circulates to the rest of the body, there is no need for the additional chambers beyond the first two.
-Fishes also have two other chambers: the sinus venosus and the bulbus arteriosus. The sinus venosus contains the pacemaker cells that initiate the contractions. The blood pumps out to the bulbus arteriosus by the ventricle. Atrium is a thin walled chamber while the ventricle is the thick walled chamber.

From the above information we have found that fishes have one ventricle and one atrium.

Hence, the correct answer is option (A).

Note: Animals that have lungs contain three to four chambered hearts. Humans contain four chambered hearts. Valves are also present in the heart to prevent backflow of the blood. Humans have a double circulatory system. Lungs purify the blood and return it to the heart again. Amphibians have three chambered hearts.