THE HEART

Hearts have become iconic symbols of Valentine’s Day but when it comes to hearts in the real world, one size doesn’t fit all — particularly in the animal kingdom. The human heart beats about 72 times a minute but in that same time, a hibernating groundhog’s heart beats just five times and a hummingbird’s heart reaches 1,260 beats per minute during flight.

What are the 4 main functions of the heart?

The four main functions of the heart are:

Pumping oxygenated blood to the other body parts.
Pumping hormones and other vital substances to different parts of the body.
Receiving deoxygenated blood and carrying metabolic waste products from the body and pumping it to the lungs for oxygenation.
Maintaining blood pressure.

DIFFERENT ANIMALS HAVE DIFFERENT TYPES OF HEARTS

1. FROGS

Frogs have a heart with just three chambers having two atria and one ventricle. In general, the heart takes deoxygenated blood from the body, sends it to the lungs to get oxygen, and pumps it through the body to oxygenate the organs. In humans, the four-chambered heart keeps oxygenated blood and deoxygenated blood in separate chambers but in frogs grooves called trabeculae keep the oxygenated blood separate from the deoxygenated blood in its one ventricle. Frogs can get oxygen not only from their lungs but also from their skin. The frog’s heart takes advantage of this evolutionary quirk as deoxygenated blood comes into the right atrium, it goes into the ventricle and out to the lungs and skin to get oxygen. The oxygenated blood comes back to the heart through the left atrium, then into the ventricle and out to the major organ. The shape of its heart is conical with thick muscular walls.

2. EARTHWORM

Earthworm doesn’t have one heart. Instead, the worm has five pseudohearts that wrap around its oesophagus. These pseudohearts don’t pump blood but rather squeeze vessels to help circulate blood throughout the worm’s body. It also doesn’t have lungs but absorbs oxygen through its moist skin.

3. ZEBRAFISH

Zebrafish can fully regenerate heart muscle just two months after 20 percent of their heart muscle is damaged. Humans can regenerate their liver and amphibians and some lizards can regenerate their tails but the zebrafish’s regenerative abilities make it a prime model to study heart growth.