Question

In which chamber of the human heart the blood is low in oxygen?
a.Right atrium
b.Right ventricle
c.Left atrium
d. a and b

Answer 1

Hint: The heart is the muscular organ which helps in the pumping of blood in most of the animals. The pumping of blood carries oxygen and various other nutrients to the body while it also carries the metabolic wastes away from the lungs.

Complete answer:
 The heart is right in the centre between the two lungs and above the diaphragm. The heart in adult humans is about the size of a closed fist of about 12 cm in length and 9 cm in width. The heart is divided into 4 chambers: the upper left and right atria and the lower left and right ventricles. It is protected by a double-walled membranous covering called the pericardium. The right atrium receives less oxygenated blood and pumps it to the right ventricles by the tricuspid valve. The right atrium pumps the less oxygenated blood to the lungs through the pulmonary veins.
The atria have a thinner wall because their main function is to receive blood from the body and pump it into the very next ventricles. The ventricles have thick muscular walls as they have to pump blood to long distances.
So, in the right atrium of the human heart, the blood is low in oxygen.
Hence, the correct answer is a.

Note: The atrium receives blood in the systole state and then it contracts to move blood to the ventricles. All animals that show a closed circulatory system consist of one atrium.