Macrophage
/ˈmækroʊˌfeɪdʒ/
A large phagocytic cell found in stationary form in the tissues or as a mobile white blood cell, especially at sites of infection.
Mastication
/ˌmæstɪˈkeɪʃən/
The process by which food is crushed and ground by teeth; chewing.
Mechanoreceptor
/ˌmɛkənoʊrɪˈsɛptər/
A sense organ or cell that responds to mechanical stimuli such as touch or sound.
Medulla Oblongata
/məˈdʌlə ˌɒblɒŋˈɡɑːtə/
The lowest part of the brainstem, controlling vital autonomic functions like breathing and heart rate.
Melanin
/ˈmɛlənɪn/
A dark brown to black pigment occurring in the hair, skin, and iris of the eye in people and animals.
Melatonin
/ˌmɛləˈtoʊnɪn/
A hormone secreted by the pineal gland that inhibits melanin formation and is thought to be concerned with regulating the reproductive cycle and sleep.
Meninges
/mɪˈnɪndʒiːz/
The three membranes (the dura mater, arachnoid, and pia mater) that line the skull and vertebral canal and enclose the brain and spinal cord.
Menstruation
/ˌmɛnstruˈeɪʃən/
The process in a woman of discharging blood and other materials from the lining of the uterus at intervals of about one lunar month.
Metabolism
/məˈtæbəˌlɪzəm/
The chemical processes that occur within a living organism in order to maintain life.
Mitochondria
/ˌmaɪtəˈkɒndriə/
An organelle found in large numbers in most cells, in which the biochemical processes of respiration and energy production occur.
Mitosis
/maɪˈtoʊsɪs/
A type of cell division that results in two daughter cells each having the same number and kind of chromosomes as the parent nucleus.
Monocyte
/ˈmɒnəˌsaɪt/
A large phagocytic white blood cell with a simple oval nucleus and clear, grayish cytoplasm.
Motor Unit
/ˈmoʊtər ˈjuːnɪt/
A single motor neuron and all the muscle fibers it innervates.
Myocardium
/ˌmaɪoʊˈkɑːrdiəm/
The muscular tissue of the heart.
Myofibril
/ˌmaɪoʊˈfaɪbrɪl/
Any of the elongated contractile threads found in striated muscle cells.
Myoglobin
/ˌmaɪəˈɡloʊbɪn/
A red protein containing heme, which carries and stores oxygen in muscle cells.
Myosin
/ˈmaɪəsɪn/
A fibrous protein that forms (with actin) the contractile filaments of muscle cells.