Practice MCQ Questions and answers on Biology-GK

Blood group AB – has both A and B antigens, but no antibodies.

The sound lub-dub lub-dub is produced by heart.

Hemoglobin is iron-containing oxygen transport protein in the red blood cells of all vertebrates. It has an oxygen binding capacity and gives the red colour to the blood.

Human red blood cells (RBC), after differentiating from erythroblasts in the bone marrow, are released into the blood and survive in the circulation for approximately 120 days. In humans and some other species, RBC normally survive in a nonrandom manner.

The upper chambers of the heart are the atria.

Purification of blood takes place in kidney.

Fully mature human RBCs has no nucleus.

For emergency transfusions, blood group type O negative blood is the variety of blood that has the lowest risk of causing serious reactions for most people who receive it. Because of this, it's sometimes called the universal blood donor type.

An organ is a group of tissues that work together to perform a specific function. In the case of heart, this function is pumping blood throughout your body. Additionally, the heart is largely made up of a type of muscle tissue called cardiac muscle.

Blood group O has no antigens, but both anti-A and anti-B antibodies in the plasma, as well as some special “anti-A,B' antibodies. Blood group AB has both A and B antigens, but no antibodies.