Protein called hemoglobin found in our blood cells carry oxygen to cells.
Hemoglobin consists of four separate polypeptide chains, and each chain is specifically designed to carry a single iron atom in its heme group. Iron has a natural affinity for oxygen, which it carries to all our cells.
When lead is present in our bloodstream, the placement of iron in the heme structure is blocked, and so hemoglobin cannot carry oxygen.
This is what's referred to as lead poisoning. It occurs when lead is breathed or consumed through contaminated water or food. Lead poisoning causes serious health problems, including brain damage and anemia.
There's more to studying than simply memorization and practice. It turns out that your diet also plays a pivotal role in recalling key bits of information, while keeping you energized and focused in the process. We're not talking about those scam-ridden supplements that promise a boost in brain power, but simple natural foods such as milk, nuts, seeds, rice, and oats.
The nutrients found in these items help your study efforts by releasing natural memory enhancers called CCKs ( cholecystokinin). When CCK crosses the blood-brain barrier, it acts as a neurotransmitter associated with memory. Studies have shown that learning and memory processes are severely damaged (in rats) that genetically do not respond to the presence of CCK. And in people ...
Asthma is one of those illnesses that is so common that we never stop to question what causes it and how it could be treated. Affecting more than 25 million people, asthma is one of the most common chronic respiratory conditions in the United States. It is caused by the increased reactivity of the tracheobronchial tree to various stimuli, including exercise, allergies, or infections of the respiratory tract. Symptoms include, but are not limited to breathlessness, cough, wheezing, and chest tightness.
Common Triggers of Asthma
The most commonly used medications for asthma are: bronchodilators, xanthine derivatives, leukotriene inhibitors, corticosteroids, and mast cell stabilizers (see full list below). Xanthine derivatives treat asthma by re ...
Genes that help control inflammation leads to longer lifespans for humans and other species, and more of these genes a species has, the longer it can live.
Genes encoding some inflammation-dampening molecules are more numerous in longer-lived species, such as humans, than in short-lived animals such as mice. The genes produce proteins known as CD33-related Siglecs. Siglecs are proteins that recognize different versions of sialic acid – sugars that are found at all cell surfaces of vertebrates and some invertebrates.
By distinguishing between different versions of sialic acid, the proteins help the immune system decide which cells are normal residents of the body and which are intruders. In addition, the proteins soothe inflammation in the aft ...
Want to reconstruct your face in 3D from a single 2D image? Now you can.
According to its creators, this technology does not require accurate alignment nor establishes dense correspondence between images; it works for arbitrary facial poses and expressions, and can be used to reconstruct the whole 3D facial geometry (including the non-visible parts of the face) bypassing the construction and fitting of a 3D Morphable Model. This is achieved via a simple convolutional neural network architecture that performs direct regression of a volumetric representation of the 3D facial geometry from a single 2D image.
The Philippine eagle (Pithecophaga jefferyi), also known as the monkey-eating eagle, is found exclusively in the forests of the Philippines. It has brown- and white-coloured plumage, and a shaggy crest, and generally measures 86 to 102 cm (2.82 to 3.35 ft) in length, weighs 4.7 to 8.0 kg (10.4 to 17.6 lb), and has a 2 meter wingspan. It is considered the largest of the extant eagles in the world in terms of length and wing surface.
Among the rarest and most powerful birds in the world, it has been declared the Philippine national bird. Unfortunately, however, it is critically endangered, mainly due to massive loss of habitat resulting from deforestation in most of its range. Killing a Philippine eagle is punishable under Philippine law by 1 ...
Approximately 10% of the world population is left-handed. What causes this anomaly?
While there are several theories that try to explain this trait -- such as the positioning of the baby during the final trimester, hormone exposure during pregnancy, or epigenetic factors -- the most consistent and hardwired explanation boils down to plain old genetics. In other words, the reason you're right-handed or left-handed is because it's written in your DNA.
Research suggests that handedness displays a complex inheritance pattern. For example, if both parents of a child are left-handed, there is a 26% chance of that child being left-handed. A large study of twins from 25,732 families also indicated that the heritability of handedness is roughly 24%.
The eruption of Mount Tambora was so massive, it erased summer that year.
The 1815 eruption of Mount Tambora was one of the most powerful eruptions in recorded history. The eruption of the volcano, on the island of Sumbawa in the Dutch East Indies (present-day Indonesia), reached a climax on 10 April 1815 and was followed by between six months and three years of increased steaming and small phreatic eruptions.
The ash from the eruption column dispersed around the world and lowered global temperatures, leading to worldwide harvest failures in an event sometimes known as the Year Without a Summer in 1816. The eruption resulted in a brief period of significant climate change that led to various cases of extreme weather. Several climate forcings ...
Richard P. Feynman (1918 - 1988) was a New York City born, Nobel Prize winner in Physics in 1965. He was an American theoretical physicist known for his work in quantum mechanics, as well as in particle physics for which he proposed the parton model.
Feynman developed a widely used pictorial representation scheme for the mathematical expressions governing the behavior of subatomic particles, which later became known as Feynman diagrams (below).
His passion for science and education later lead him to develop a universal learning model, now called the Feynman Technique, that could help you learn practically anything no matter how difficult or complicated. As long you or the educator uses simple terminology (no complicated words or terms), you ...
Many great minds have sought proof for God's existence. For French philosopher and scientist, Blaise Pascal, God's existence was beside the point. He conceded that nobody knows whether or not God exists, but because it's in our own best interests to behave as if He does, that's the most rational choice.
This is what's known as Pascal's Wager, since it argues that it's your best bet to believe in God. (Pascal wrote of the Christian God, but this same argument could apply to any god). If God doesn't exist and you behave as if he does, you haven't lost much - just some sleep on Sunday and a few opportunities for sin. But if God does exist, you have everything to lose or gain: act as if he does exist and you spend eternity in heaven; act as if h ...
The hairy frogfish (Antennarius striatus) is a marine fish with spines resembling strands of hair - and it can change color. This small fish grows up to 22 cm (8.7 in) long, and has a rounded, extensible body. Its large mouth is forwardly extensible, allowing it to swallow prey as large as itself! The coloring of its body is extremely variable because individual fish tend to match their living environments.
Frogfishes have the capacity to change coloration and pigment pattern, taking only a few weeks to adapt. The dominant coloration varies from yellow to brownish-orange, passing through a range of shades, but it can also be green, gray, brown, almost white, or even completely black without any pattern. Body and fins can be marked with roug ...
Nearly 80% of U.S. dairy cows have their horns removed each year to protect their handlers and fellow cattle. But the practice, which is both painful and expensive, has come under increasing scrutiny from animal rights activists. Now, science may be coming to the rescue: A group of researchers announced last week that they successfully edited the genomes of dairy cows to make them hornless. The scientists used the transcription activator-like effector nucleases DNA editing technique to introduce a natural allele linked to hornlessness into dairy cow embryos. Five healthy calves were born, all without horns (above, left), the researchers report in a letter in Nature Biotechnology. The allele - called POLLED - is much more common in beef catt ...
Nearly one-third of women experience heavy periods each month. This means that unlike normal periods where women lose up to 40 mL of blood per cycle, some women lose as much as 80 mL (more than a quarter of a cup) in at least one cycle throughout their life. Scientists think they might have found the answer as to why this happens, and they are blaming it on a non-hormonal protein. A new small study suggests that low levels of a specific protein known as hypoxia-inducible factor 1 (HIF1, right) might be to blame.
HIF1 is a pretty handy healing molecule. When oxygen levels drop in parts of the body, a condition known as hypoxia, HIF1 activates more than 60 genes linked to tissue regeneration, and has already been shown to play a role in repai ...
The northern bald ibis (Geronticus eremita) was thought to be extinct until it was rediscovered in the Syrian desert near Palmyra in 2002. Habitat disturbance and hunting are the main drivers behind the bird's decline in its Middle Eastern habitat.
This glossy black ibis ranges in size from 70 to 80 cm (28 to 31 inches) glossy black ibis, has an unfeathered red face and head, and a long, curved red bill. It breeds colonially on coastal or mountain cliff ledges, where it typically lays two to three eggs in a stick nest, and feeds on lizards, insects, and other small animals.
According to a Turkish legend, the northern bald ibis was one of the first birds that Noah released from the ark, as a symbol of fertility. ...
This species, known as the bobbit worm (Eunice aphroditois), is a carnivorous worm that usually makes it home by digging a vertical burrow in the sand between rocks or corals in a tropical reef. The burrow is barely wider than the creature's body, but must be as deep as the worm is long. The bobbit worm finds prey with five long antennae on the top of its "head". These antennae wave in the current, picking up scents of possible prey in the water as they flow by and letting the worm know a meal might be near. Not only does it strike at its prey with sharpened jaws, it injects a toxin, which stuns or kills it. The worm can grow up to ten feet in length and eats mostly crustaceans and mollusks.
