Human hair colorHuman hair color is the pigmentation of human hair follicles due to two types of melanin: eumelanin and pheomelanin. Generally, if more melanin is present, the color of the hair is darker; if less melanin is present, the hair is lighter. The tone of the hair is dependent on the ratio of black or brown eumelanin to yellow or red pheomelanin. Levels of melanin can vary over time causing a person's hair color to change, and it is possible to have hair follicles of more than one color on the same person.
Sequence analysisIn bioinformatics, sequence analysis is the process of subjecting a DNA, RNA or peptide sequence to any of a wide range of analytical methods to understand its features, function, structure, or evolution. Methodologies used include sequence alignment, searches against biological databases, and others. Since the development of methods of high-throughput production of gene and protein sequences, the rate of addition of new sequences to the databases increased very rapidly.
Sequence logoIn bioinformatics, a sequence logo is a graphical representation of the sequence conservation of nucleotides (in a strand of DNA/RNA) or amino acids (in protein sequences). A sequence logo is created from a collection of aligned sequences and depicts the consensus sequence and diversity of the sequences. Sequence logos are frequently used to depict sequence characteristics such as protein-binding sites in DNA or functional units in proteins. A sequence logo consists of a stack of letters at each position.
ChromatophoreChromatophores are cells that produce color, of which many types are pigment-containing cells, or groups of cells, found in a wide range of animals including amphibians, fish, reptiles, crustaceans and cephalopods. Mammals and birds, in contrast, have a class of cells called melanocytes for coloration. Chromatophores are largely responsible for generating skin and eye colour in ectothermic animals and are generated in the neural crest during embryonic development.
Melanocytic nevusA melanocytic nevus (also known as nevocytic nevus, nevus-cell nevus and commonly as a mole) is usually a noncancerous condition of pigment-producing skin cells. It is a type of melanocytic tumor that contains nevus cells. Some sources equate the term mole with "melanocytic nevus", but there are also sources that equate the term mole with any nevus form. The majority of moles appear during the first two decades of a person's life, with about one in every 100 babies being born with moles.
Neural grooveThe neural groove is a shallow median groove of the neural plate between the neural folds of an embryo. The neural plate is a thick sheet of ectoderm surrounded on either side by the neural folds, two longitudinal ridges in front of the primitive streak of the developing embryo. The groove gradually deepens as the neural folds become elevated, and ultimately the folds meet and coalesce in the middle line and convert the groove into a closed tube, the neural tube or canal, the ectodermal wall of which forms the rudiment of the nervous system.
ForebrainIn the anatomy of the brain of vertebrates, the forebrain or prosencephalon is the rostral (forward-most) portion of the brain. The forebrain (prosencephalon), the midbrain (mesencephalon), and hindbrain (rhombencephalon) are the three primary brain vesicles during the early development of the nervous system. The forebrain controls body temperature, reproductive functions, eating, sleeping, and the display of emotions.
DiencephalonThe diencephalon (or interbrain) is a division of the forebrain (embryonic prosencephalon). It is situated between the telencephalon and the midbrain (embryonic mesencephalon). The diencephalon has also been known as the 'tweenbrain in older literature. It consists of structures that are on either side of the third ventricle, including the thalamus, the hypothalamus, the epithalamus and the subthalamus. The diencephalon is one of the main vesicles of the brain formed during embryogenesis.