white

Optical spectrum

...g the phenomenon of colored bands dispersing from white sunlight passing through a prism . Explanation of Newton's experiment When a beam of sunlight strikes the face of a glass prism at an angle, some is reflected and some of the beam passes into the glass. All light travels at the same speed in a ...

Thomas Hunt Morgan

...eir progeny were all red-eyed, suggesting that the white eye trait was recessive. Morgan thus named the gene white , starting the tradition of naming genes after their mutant allele . As Morgan continued to cross-...

Stem cell

...n the bone marrow produce large amounts of red and white blood cells, to keep the body healthy and to help fight infections . Since the 1980s stem cells have been taken from the blood instead of the bone-marrow, making the procedure safer for older people. Although normally scarce, the number of perip...

Species

...populations have black backs, southern populations white backs, and there is an extensive hybrid zone where both 'pure' types are common, as are crossbreeds. The variation in Koalas is clinal (a smooth transition from north to south, with populations in any given small area having a uniform appearance), bu...

Red Queen

...o help the bear survive the cold of the arctic and white in order that the bear can stalk seals for food. For the first case the selection pressure is likely to be constant or subject to random change, in the second case the selection pressure is likely to increase steadily as selection for cautiousness...

Protein

...ans usually do not have this problem, since egg's white and cow's milk contain all essential amino acids. Peanuts , soy milk, nuts, seeds, green peas, Legumes , the alga spirulina and some grains are some of the richest sources of plant protein. All eight essential amino acids must be part of o...

Pigment

...of selective absorption, there is no such thing as white pigment. A white object is simply a diffuse reflecting object which does not contain any pigment. In the coloring of...

Malpighian corpuscle

...dneys White Nodules — follicles in the white pulp of the spleen , containing many lymphocytes These structures are named after Marcello Malpighi (1628-1694), an Italian physician and biologist regarded as the father of microscopical anatomy and histology ....

Leaf

...s. tomentose: densely pubescent with matted, soft white woolly hairs. cano-tomentose: between canescent and tomentose felted-tomentose: woolly and matted with curly hairs. villous: with long and soft hairs, usually curved. woolly: with long, soft and tortuous or matted hairs. Leaf surfaces Th...

Immune system

...microbial products, complements, damaged cells and white blood cell fragments; chemotaxis is followed by a...m is based on immune cells called leukocytes (or white blood cells) that are produced by stem cells in the bone marrow . In many species, including mam...

Homunculus

...ugh the shell, replace a bean-sized portion of the white with human sperm, seal the opening with virgin parchment, and bury the egg in dung on the first day of the March lunar cycle. A miniature humanoid would emerge from the egg after thirty days, which would help and protect its creator in return for a s...

Heterozygote

...ink flower and pp for the recessive homozygote white flower. When these are crossed, the F1 or second g...are intermediary: the red carnation crossed with a white carnation will give you heterozygote pink carnations. See also homozygote dominant gen...

Helper T cell

...er (or T H ) T cell is a T cell (a type of white blood cell ) which has on its surface antigen receptors that can bind to fragments of antigens displayed by the Class II MHC molecules found on professional antigen-presenting cells (APCs). Once bound to an antigen, the T H cell proliferates a...

Glycoprotein

...ften show a high viscosity , for example, in egg white and blood plasma . See also Proteoglycan Abeta [1]...

Fungus

...ungi are popular as food : Shiitake mushrooms , white mushrooms , puffballs , Morels, truffles and Mexican Corn smut are examples. Some mushrooms are also ingested recreationally for their hallucinogenic properties. Many other mushrooms are extremely poisonous (see Mushroom poisoning ). While not ...

Drosophila

...female fruit fly lays batches of between 15 and 20 white eggs each day." (Burton) A female lays up to 2000 pearly white eggs, each with a pair of “wings” or respiratory “horns” near the anterior e...

Cytotoxic T cell

...ic (or T C ) T cell is a T cell (a type of white blood cell ) which has on its surface antigen receptors that can bind to fragments of antigens displayed by the Class I MHC molecules of virus infected somatic cells and tumor cells. Once activated by a MHC-antigen complex, T C cells release...

Collagen

...issue due to a lack of or defective collagen. The white collagen that makes up the matrix of most connective tissue in mammals consists of inter-woven fibres of the protein collagen. The collagen fibres consist of globular units of the collagen sub-unit tropocollagen . Tropocollagen sub-units spontaneous...

Chlorophyll

...aves have green areas that contain chlorophyll and white areas that have none.) When tested with iodine solution , a color change revealing the presence of starch occurs only in regions of the leaf that were green and therefore contained chlorophyll. This shows that photosynthesis does not occur in areas w...

Cartilage

...ic. Fibrocartilage Fibrocartilage (also called white cartilage) is a specialised type of cartilage found in areas requiring tough support or great tensile strength, such as between intervertebral disks, the pubic symphisys and at sites connecting tendons or ligaments to bones . There is rarely any...

Cancer

...ially the same overall cancer incidence rates, but white infants have substantially higher cancer rates than black infants for most cancer types. Relative survival for infants is very good for neuroblastoma, Wilms' tumor and retinoblastoma , but not for most other types of cancer. Childhood cancers inc...

Brain

...yered, networked and convoluted grey matter and white matter . Grey matter refers to tissue mostly compr...g myelin insulation, which gives this tissue its white color. White matter is found in bundles of fibers known as tracts which connect the different parts ...

Full blood count

...luted) are used to calculate the number of red and white cells per litre of blood. To identify the numbers of different white cells, a blood film is made, and a large number of white cells (at least 100) are counted. This gi...

Blood

...of fluid plasma and cells ( red blood cells , white blood cells , platelets ). Medical terms related to blood often begin in hemo- or hemato- ( BE : haemo- and haemato- ) from the Greek word " haima " for "blood". The main function of blood is to supply nutrients ( oxygen , glucose ) and c...

Arabidopsis

...hown both negative phototropic response to blue or white light, and positive phototropic response to red light. The photosensitive pigments phytochrome A and phytochrome B mediate this red light based phototropic response. Common names include Thale Cress, Mouse-ear Cress, and Mustard Weed....

Allele

...esult in red petals, while another might result in white petals. Some organisms are diploid - that is, t...le, in a heterozygous flower (with one red and one white allele), the petals will be red. The recessive allele will only be expressed in a recessive homozygo...

Alexander Fleming

...ccus luteus - yellow Micrococcus varians - white Micrococcus roseus - pink Bacillus sp. - orange Fleming died in 1955 of a heart attack . He was buried as a national hero in the crypt of St. Paul's Cathedral in London. His discovery of penicillin had changed the world of modern m...

Albumin

...on of all plasma protein. It is also found in egg white . The normal range of albumin concentrations in human blood is 3.5 to 5.0 g/dL, and albumin normally constitutes about 60% of plasma protein; all other proteins present in blood plasma are referred to collectively as globulin .Albumin is essent...

Albinism

...generally have flax-white hair, blue eyes and pale white skin which makes them stand out. Sometimes hair pi...aking a picture with a film camera that is painted white within, rather than black. Such sensitivity generally leads to a dislike of bright lights, but does ...

Absorption spectrum

...avelengths emitted by a material. Let us consider white light, which consists of electromagnetic radiation at all frequencies, passing through a sample of cold gas. For any collection of atoms or molecules , there are certain specific amounts of energy required to change state; for individual atoms, ...