Question

How many hearts does a shark have?

Answer 1

Hint: In most animals, the heart is a muscular organ that pumps blood via the circulatory system's blood arteries. The pumping blood transports oxygen and nutrients to the body, as well as metabolic waste like carbon dioxide, to the lungs. The heart in humans is about the size of a closed fist and is positioned in the middle compartment of the chest, between the lungs.

Complete answer:
Sharks are elasmobranch fish with a cartilaginous skeleton, five to seven gill slits on the sides of the head, and unfused pectoral fins. Modern sharks belong to the clade Selachimorpha, which is the sister group of rays. However, outside of the Selachimorpha, the word "shark" has been applied to extinct members of the Elasmobranchii subclass, such as Cladoselache and Xenacanthus, as well as other Chondrichthyes, such as the holocephalid eugenedontidans.
Sharks have a two-chambered heart and have a single-circuit circulatory system. The heart pumps blood to the gills, where it is oxygenated. Before returning to the heart, this oxygen-rich blood is transported throughout the body and to the tissues. Deoxygenated blood enters the sinus venosus when the heart beats. The blood then travels from the atrium to the ventricle, where it is emptied into the conus arteriosus and exits the heart. The heart of a shark has two chambers: an atrium (also known as the auricle) and a ventricle. The heart of a shark is an S-shaped tube found in the shark's head.
The heart pumps blood to capillaries in the gills via the afferent branchial arteries (ventral aorta) (where the blood is oxygenated). The blood subsequently passes through different branchial arteries (paired dorsal aorta), body tissues, and veins before returning to the heart.

Note:
Humans have four chambers in their hearts, but sharks only have two chambers. Humans also do not require continual movement to circulate their blood since our blood pressures are greater and we can maintain our body temperatures using dietary energy. The majority of sharks have a cold blooded nature. Some sharks, such as the Mako and Great White, are partially warm-blooded (they are endotherms). These sharks can elevate their body temperature to that of the water, but they need to hunt with brief bursts of speed every now and then.