43 results found

Search Results for: melanin

Hypomelanism

All the body cells of living organisms bear some color due to one or the other pigment molecule or complex. The pigment can... Read More

Eumelanin

Definition noun An aggregate of pigment molecules, each made up of cross-linked 5,6-dihydroxyindole (DHI) and... Read More

Neuromelanin

Definition noun A type of melanin pigment present in parts of the brain, particularly in the neurons of substantia nigra and... Read More

Melanin

Definition noun A group of insoluble pigments found in melanophores and produced from the oxidation of tyrosine, followed by... Read More

Pheomelanin

Definition noun A type of melanin pigment that is made up of benzothiazine units and is responsible for yellow and pink to... Read More

Amelanism

Definition noun A condition characterized by the complete lack of pigments (or melanin) Supplement Melanin is a compound... Read More

Family traits

When one thinks of family, they often think of persons who are blood-related to each other as parents to their children and... Read More

Albino

Definition noun, plural: albaninos An organism with albinism, which is a condition characterized mainly by a lack of or an... Read More

Polygenic inheritance

Polygenic inheritance refers to the kind of inheritance in which the trait is produced from the cumulative effects of many... Read More

Melanophore

Definition noun, plural: melanophores A type of pigment cell that, in particular, produce and store... Read More

Albinism

Definition noun A hereditary, congenital disorder characterized by the complete or partial lack of pigmentation production... Read More

Melanocyte

Definition noun, plural: melanocytes A type of pigment cell that, in particular, produce melanin, and occurs in the... Read More

Melanosome

Definition noun, plural: melanosomes An organelle in pigment cell that synthesizes and stores melanin Supplement A... Read More

Melanogenesis

Definition noun The process of producing melanin Supplement Melanogenesis is the process of melanin production. Melanocytes... Read More

Melanism

Definition noun The condition wherein an unusually high amount of melanin is produced and deposited resulting in the dark... Read More

Melanocyte-stimulating hormone

Definition noun, plural: melanocyte-stimulating hormones A peptide hormone in vertebrates that primarily regulate melanin... Read More

Genetic Control – On and Off Genes

Reviewed by: Mary Anne Clark, Ph.D. This lesson looks at the various factors involved that affect growth and... Read More

Polygenic trait

Polygenic Trait Definition Polygenic trait refers to a trait that is controlled by multiple non-allelic genes. These genes... Read More

Chromatophore

Definition noun, plural: chromatophores A pigment-containing cell or light-reflecting structure, especially found in fish,... Read More

Cell wall

The cell is the structural, functional, and biological unit of all organisms. It is a membrane-bound structure containing... Read More

photobiology

Photobiology Definition Photobiology, the biology of light, is a subdiscipline in biology. It focuses on the effects of... Read More

Fitness

A competing variant's frequency is rising in relation to other competing variants in a population under the biological... Read More

Evolution

Evolution Definition Evolution is defined as a change in the genetic composition of a population over successive... Read More

Complete dominance

Complete Dominance Definition Genetics is the study of how traits are inherited by organisms and in what ways these... Read More

Chlorophyll

Why are most plants green? Have you ever had the same question? Perhaps, you’ve been told that the plants are green... Read More

Incomplete dominance

Incomplete Dominance Definition After Gregor Mendel discovered inheritance laws, the term ''incomplete dominance'' was... Read More

Melanoderma

melanoderma 1. An abnormal darkening of the skin by deposition of excess melanin. 2. Hyperpigmentation of the skin by... Read More

Genetic Mutations

Reviewed by: Mary Anne Clark, Ph.D. Genetic Mutations Genetic mutations are inherited variations in an... Read More

Pleiotropy

Pleiotropy Definition When one single gene starts affecting multiple traits of living organisms, this phenomenon is known... Read More

Adaptive Radiation

Reviewed by: Mary Anne Clark, Ph.D. When Charles Darwin was in the Galapagos Islands, one of the first things he... Read More

Epidermis

Epidermis Definition What is the epidermis? We can define the epidermis as one or more layers of cells forming the tough... Read More

Degenerative disease

Degenerative Disease Definition A degenerative disease is defined as a disease characterized by the worsening condition due... Read More

Pioneer species

You might have come across news of some barren lands turning into luscious grasslands or forests after decades? Or you might... Read More

Sexual selection

What is Sexual Selection? The definition of sexual selection is very interesting in biological terms. The sexual selection... Read More

Integumentary system

Integumentary System Definition The integumentary system is the outermost layer of the body. The animal body, in... Read More

Organelle

The cell is regarded as the structural, functional, and biological unit of all organisms. It is a membrane-bound structure... Read More

Lipotropin

Definition noun, plural: lipotropins A polypeptide hormone of the anterior pituitary gland, presumably acts by promoting fat... Read More

Frameshift mutation

Define Frameshift Mutation What is a frameshift mutation? In biology, insertions or deletions of nucleotides in the coding... Read More

Basal layer

Definition noun (1) The innermost layer of the epidermis made up of basal or germinative cells capable of proliferating by... Read More

Epistasis

Epistasis Definition What is epistasis in genetics? How does epistasis occur? The epistasis definition, in biology, refers... Read More