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Hypocholesterolemia is the presence of abnormally low ( hypo-) levels of cholesterol in the blood ( -emia ). A defect in the body's production of cholesterol can lead to adverse consequences as well. Cholesterol is an essential component of mammalian cell membranes and is required to establish proper membrane permeability and fluidity.
Low-density lipoprotein ( LDL) is one of the five major groups of lipoprotein that transport all fat molecules around the body in extracellular water. [1] These groups, from least dense to most dense, are chylomicrons (aka ULDL by the overall density naming convention), very low-density lipoprotein (VLDL), intermediate-density lipoprotein (IDL ...
A representation of the 3D structure of the protein myoglobin showing turquoise α-helices. This protein was the first to have its structure solved by X-ray crystallography. Toward the right-center among the coils, a prosthetic group called a heme group (shown in gray) with a bound oxygen molecule (red). Proteins are large biomolecules and ...
This article is about the physical properties of greenhouse gases. For how human activities are adding to greenhouse gases, see Greenhouse gas emissions. Greenhouse gases trap some of the heat that results when sunlight heats the Earth's surface. Three important greenhouse gases are shown symbolically in this image: carbon dioxide, water vapor ...
Budget. $6.83 billion (2024–25) Website. who.int. The World Health Organization ( WHO) is a specialized agency of the United Nations responsible for international public health. [2] It is headquartered in Geneva, Switzerland, and has six regional offices [3] and 150 field offices worldwide. [4] The WHO was established on April 7, 1948, and ...
t. e. The viscosity of a fluid is a measure of its resistance to deformation at a given rate. [1] For liquids, it corresponds to the informal concept of "thickness": for example, syrup has a higher viscosity than water. [2] Viscosity is defined scientifically as a force multiplied by a time divided by an area.
The earliest datable record of an aurora was recorded in the Bamboo Annals, a historical chronicle of the history of ancient China, in 977 or 957 BC. An aurora was described by the Greek explorer Pytheas in the 4th century BC. Seneca wrote about auroras in the first book of his Naturales Quaestiones, classifying them, for instance, as pithaei ('barrel-like'); chasmata ('chasm'); pogoniae ...
