M

mastication
Chewing.
maternal
Pertaining to the mother.
maternal recognition of pregnancy
A process by which the early embryo sends signals to maternal tissues to allow continuation of the pregnancy.
medial
Toward the midline of the body. The inner surface of your leg is the medial surface.
melatonin
A hormone secreted from the pineal gland.
mesenchyme
The embryonic precursor to all connective tissues. Mesenchymal cells differentiate into fibroblasts, adipocytes, endothelial cells, etc.
mesentery
A extension of the peritoneum that wraps around the intestines and suspends them from the dorsal body wall.
mesothelium
A thin layer of flattened cells, derived from mesoderm, that lines body cavities and covers internal organs.
meta-
A prefix indicating either 1) change, transformation or exchange, or 2) after or next.
metacentric
A chromosome structure in which the centromere is roughly equidistant between the two ends.
metaplasia
Change from one type of cell or tissue to another. For example, connective tissue undergoes metaplasia to form cartilage or bone. Columnar epithelial cells can undergo "squamous metaplasia" to form squamous-type epithelial cells in response to chronic irritation.
microvilli
Thin cylindrincal projections of the plasma membrane that are particularly abundant on epithelial cells in the small intestine.
migrating motor complex
A pattern of neural and motor activity that occurs in the gastrointestinal tract between meals.
mineralocorticoid
A type of steroid hormone synthesized and secreted from the adrenal cortex. The major mineralocorticoid is aldosterone.
morphology
The study of form and structure. The morphology of an apple would include a description of its skin, stem, core, seeds, fruit, and how they are arranged as a whole.
morula
A stage during early embryogenesis in which the embryo resembles a mulberry (roughly 16 to 32 cells).
mosaic (mosaicism)
In genetics, an animal that has more than one genetically-distinct populations of cells derived from a single zygote; as most commonly used, the different populations of cells have differing numbers of chromosomes.
motilin
A peptide hormone secreted from the small intestine that appears to stimulate intestinal smooth muscle contractions in periods between meals.
motility
The ability to move. This term is applied to such things as smooth muscle contractions that cause the intestine to contract or the motion of the sperm tail which enables it to swim.
mucins
A family of large glycoproteins that are the major constituent of mucus.
mucosa
The innermost tunic or "lining" of body cavities that are exposed to the exterior (e.g. digestive, reproductive and respiratory tracts). The same as "mucous membrane".
mucous membrane
The lining of a body cavity exposed to the exterior - see mucosa.
murine
Pertaining to rats or mice.
myenteric plexus
A group of autonomic neurons in the enteric nervous system; also known as the plexus of Auerbach.
myxedema
A severe form of thyroid hormone deficiency.

Last updated on 10/2/2004