Engineering

A contact lens that can show when blood glucose levels are high

A team of researchers affiliated with several institutions in the Republic of Korea has developed a contact lens with a tiny LED light that turns on and off to show blood glucose levels. In their paper published in the journal ...

Robotics

Microscopic robots 'walk' thanks to laser tech

A Cornell University-led collaboration has created the first microscopic robots that incorporate semiconductor components, allowing them to be controlled—and made to walk—with standard electronic signals.

Hardware

OmniVision announces world record for smallest image sensor

OmniVision, a developer of advanced digital imaging solutions, has announced that it has won a place in the Guinness Book of World Records with the development of its OV6948 image sensor—it now holds the record for the ...

Engineering

Wearable ultrasound patch monitors blood pressure deep inside body

A new wearable ultrasound patch that non-invasively monitors blood pressure in arteries deep beneath the skin could help people detect cardiovascular problems earlier on and with greater precision. In tests, the patch performed ...

Robotics

Life-like robots soon to be reality

Life-like robots that can make decisions, adapt to their environment and learn, are one step closer thanks to a University of Bristol team who has demonstrated a new way of embedding computation into soft robotic materials. ...

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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