basal membrane

basal membrane,

a sheet of tissue that forms the outer layer of the choroid and lies just under the pigmented layer of the retina. It is composed of elastic fibers in an otherwise thin homogenous layer.

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basal

pertaining to or situated near a base; in physiology, pertaining to the lowest possible level.

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basal body

the structure that acts as a template for the characteristic 9 + 2 arrangement of the microtubules of eukaryotic cilia and flagella.

basal cell tumors

neoplasms of the multipotential cells within the stratum germinativum of the skin. They are common in dogs and cats, are locally expansive and do not metastasize.

basal energy requirements (BER)

see energy requirements.

basal ganglia

a collection of masses of gray matter at the base of the cerebral hemispheres, subthalamus and midbrain which are responsible for much of the organization of the activity of somatic muscles. The individual nuclei are the caudate nucleus, putamen, globus pallidus, endopeduncular nucleus, subthalamic nucleus and the substantia nigra. Other nuclei which have a similar function but are usually not included in the group are the amygdaloid nuclei and the red nucleus.

basal layer

see stratum basale.

basal membrane

the deepest layer of the epidermis in the avian skin. Called also dermoepidermal junction.

basal metabolic rate

see metabolic rate.

basal metabolism

the minimal energy expended for the maintenance of respiration, circulation, peristalsis, muscle tonus, body temperature, glandular activity and the other vegetative functions of the body. See also metabolic rate.

basal metabolism test

a method of measuring the body's expenditure of energy by recording its rate of oxygen intake and consumption. Once a major test of thyroid gland function, it is being replaced by diagnostic tests requiring less extensive preparation and capable of producing more accurate test results, e.g. the determination of the levels of thyroid hormones in the blood and the radioiodine uptake test.

basal nuclei

see basal ganglion.

basal plate

the ventral plate of the developing neural tube of the embryo; associated with motor output from the CNS.

basal tone

degree of contractile tension remaining in blood vessels after complete elimination of all external excitatory influences.