Animals & Science

You might not think humans have anything in common with fish, reptiles or birds. Yet all are vertebrates with immune systems that include white blood cells. Immune systems are developed best in...

The skeletal system is a complex collection of bones joined together into a form that aids the human body in a number of ways that help us. In addition to providing general structure, bones have a...

The circulatory system and the respiratory system work closely together to ensure that organ tissues receive enough oxygen. Oxygen is required for cellular functions. The air breathed in and held...

Three types of blood vessels are found in the human body: arteries, veins, and capillaries. Arteries typically carry oxygenated blood away from the heart with the exception of the pulmonary...

The ABO blood group is the most commonly known group of blood types. While scientists still do not understand the evolutionary importance of these blood types, they play an important role in...

When having blood tests done, a patient will receive a report from the doctor. The report lists several levels of cells and enzymes in the body. Liver enzymes, biomolecules, electrolytes and blood...

Plasmodium is a small single celled organism responsible for malaria. Plasmodium is a large genus that has several species, but only a few cause disease in humans. Plasmodium is spread through a...

The valves of the heart are responsible for controlling blood flow. In a healthy body, blood flow is one-way. Blood that is able to leak back into other chambers of the heart causes heart disease...

Measuring blood pressure is a part of a typical checkup. Patients who go to the doctor for any procedure routinely have their blood pressure taken. Blood pressure is a basic yet important part of...

The circulatory system is the process in the human body where blood is cycled through blood vessels, the heart and the lungs. The circulatory keeps tissue in the body filled with oxygen, which is...

The cardiovascular system is responsible for bring oxygenated blood to tissue and eliminating metabolic waste and carbon dioxide. The cardiovascular system is controlled by the heart as it pumps...

Blood is made up of three parts: red cells, white cells and platelets. Red blood cells are responsible for the oxygen delivery from the lungs to the tissue in the body. White blood cells are a...

The lungs are the organs that are responsible for gas exchange. Oxygen enters the body through the trachea and down to the lungs, where blood is pumped in from the heart. The lungs are also...

The circulatory system is the body's way of bringing oxygen and nutrients to cells. The circulatory system delivers nutrients and oxygen to cells through the blood. The metabolic waste from...

The skeletal system is responsible for protection of organs and support for movement. Without the skeleton, humans would be unable to move or support the body for upright posture. The skeletal...

The respiratory system of the human body is responsible for providing oxygen and carbon dioxide exchange. The heart pumps blood to the lungs where bronchial tubes remove carbon dioxide from the...

All cells in the human body contain the DNA necessary for life. Cells that comprise certain tissue have different active genes than other tissue. For instance, liver tissue cells produce different...

Every system in the body has organs that produce the necessary functions for life. Each human organ is comprised of tissue that enables its function. For instance, the proteins synthesized in the...

Unlike the mythical creature they are often associated with, vampire bats do exist. Vampire bats include three species of bats that live in Central and South America: the common vampire bat...

Blood vessels are the large network of arteries, veins, capillaries and arterioles that make up a part of the circulatory system. The flow of blood is controlled by the heart, but the vessels are...

The blood is the liquid that circulates throughout the body, bringing nutrients and oxygen to the cells. Blood also carries white blood cells that are responsible for clearing infections and...

Antibodies are proteins used by the immune system to ward off bacteria and viruses. Typically, they are manufactured and dispersed into the blood stream by plasma cells, which are also known as...

Peripheral blood is the flowing, circulating blood of the body. It is composed of erythrocytes, leukocytes and thrombocytes. These blood cells are suspended in blood plasma, through which the...

Water that is inhabited by fish contains oxygen that is dissolved into the water. However, the water contains only 1/20 the amount of oxygen in it that air does. Fish, then, need some way of...

They use their feathers. Not only can feathers keep a penguin warm, they can also keep one cool. This is because, unlike fur, they can be puffed out for ventilation. With their feathers puffed up,...