Diseases, Conditions, Syndromes

Study examines role of hyperglycemia in COVID-19 severity

As COVID-19 continues to rage across the U.S., researchers are digging deeper into how the virus wreaks havoc on the body, especially for those with a pre-existing chronic illness.

Diseases, Conditions, Syndromes

Malaria discovery could expedite antiviral treatment for COVID-19

The study, conducted by an international team and led by RMIT University's Professor Christian Doerig, outlines a strategy that could save years of drug discovery research and millions of dollars in drug development by repurposing ...

Medical research

Using models, 3-D printing to study common heart defect

One of the most common congenital heart defects, coarctation of the aorta (CoA) is a narrowing of the main artery transporting blood from the heart to the rest of the body. It affects more than 1,600 newborns each year in ...

Medications

Cannabidiol improves blood flow to brain's hippocampus

A single dose of cannabidiol (CBD) helped increase blood flow to the hippocampus, an important area of the brain associated with memory and emotion, finds a new study led by UCL researchers.

Diseases, Conditions, Syndromes

Coronavirus-related children's diseases linked to blood cell changes

A newly described disease occurring in children and linked to COVID-19 has significant changes in white blood cells—a discovery that may allow doctors to better assess their young patients' condition and predict their resistance ...

Psychology & Psychiatry

What stress does to the body and how to beat it

From daily struggles like work pressure to traumatic events like the death of a loved one, everyone has felt some form of stress. People also are experiencing new stressors caused by a global pandemic. Although stress can ...

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Blood

Blood is a specialized bodily fluid that delivers necessary substances to the body's cells — such as nutrients and oxygen — and transports waste products away from those same cells.

In vertebrates, it is composed of blood cells suspended in a liquid called blood plasma. Plasma, which comprises 55% of blood fluid, is mostly water (90% by volume), and contains dissolved proteins, glucose, mineral ions, hormones, carbon dioxide (plasma being the main medium for excretory product transportation), platelets and blood cells themselves. The blood cells present in blood are mainly red blood cells (also called RBCs or erythrocytes) and white blood cells, including leukocytes and platelets. The most abundant cells in vertebrate blood are red blood cells. These contain hemoglobin, an iron-containing protein, which facilitates transportation of oxygen by reversibly binding to this respiratory gas and greatly increasing its solubility in blood. In contrast, carbon dioxide is almost entirely transported extracellularly dissolved in plasma as bicarbonate ion.

Vertebrate blood is bright-red when its hemoglobin is oxygenated. Some animals, such as crustaceans and mollusks, use hemocyanin to carry oxygen, instead of hemoglobin. Insects and some molluscs use a fluid called hemolymph instead of blood, the difference being that hemolymph is not contained in a closed circulatory system. In most insects, this "blood" does not contain oxygen-carrying molecules such as hemoglobin because their bodies are small enough for their tracheal system to suffice for supplying oxygen.

Jawed vertebrates have an adaptive immune system, based largely on white blood cells. White blood cells help to resist infections and parasites. Platelets are important in the clotting of blood. Arthropods, using hemolymph, have hemocytes as part of their immune system.

Blood is circulated around the body through blood vessels by the pumping action of the heart. In animals having lungs, arterial blood carries oxygen from inhaled air to the tissues of the body, and venous blood carries carbon dioxide, a waste product of metabolism produced by cells, from the tissues to the lungs to be exhaled.

Medical terms related to blood often begin with hemo- or hemato- (also spelled haemo- and haemato-) from the Ancient Greek word αἶμα (haima) for "blood". In terms of anatomy and histology, blood is considered a specialized form of connective tissue, given its origin in the bones and the presence of potential molecular fibers in the form of fibrinogen.

This text uses material from Wikipedia, licensed under CC BY-SA