In the developing

nervous system In biology, the nervous system is the highly complex part of an animal that coordinates its actions and sensory information by transmitting signals to and from different parts of its body. The nervous system detects environmental changes th ...

, the basal plate is the region of the

neural tube In the developing chordate (including vertebrates), the neural tube is the embryonic precursor to the central nervous system, which is made up of the brain and spinal cord. The neural groove gradually deepens as the neural fold become elevated, a ...

ventral to the

sulcus limitans The sulcus limitans is found in the fourth ventricle of the brain. It separates the cranial nerve motor nuclei (medial) from the sensory nuclei (lateral).Nolte, John. The Human Brain 6th ed. p.685. Mosby Inc. It can also be located by searching ...

. It extends from the rostral

mesencephalon The midbrain or mesencephalon is the forward-most portion of the brainstem and is associated with vision, hearing, motor control, sleep and wakefulness, arousal (alertness), and temperature regulation. The name comes from the Greek ''mesos'', "m ...

to the end of the

spinal cord The spinal cord is a long, thin, tubular structure made up of nervous tissue, which extends from the medulla oblongata in the brainstem to the lumbar region of the vertebral column (backbone). The backbone encloses the central canal of the spi ...

and contains primarily motor

neuron A neuron, neurone, or nerve cell is an electrically excitable cell that communicates with other cells via specialized connections called synapses. The neuron is the main component of nervous tissue in all animals except sponges and placozoa. N ...

s, whereas neurons found in the

alar plate Daminozide—also known as aminozide, Alar, Kylar, SADH, B-995, B-nine, and DMASA,—is a plant growth regulator, a chemical sprayed on fruit to regulate growth, make harvest easier, and keep apples from falling off the trees before they ripen s ...

are primarily associated with sensory functions. The cell types of the basal plate include

lower motor neuron Lower motor neurons (LMNs) are motor neurons located in either the anterior grey column, anterior nerve roots (spinal lower motor neurons) or the cranial nerve nuclei of the brainstem and cranial nerves with motor function (cranial nerve low ...

s and four types of interneuron. Initially, the left and right sides of the basal plate are continuous, but during neurulation they become separated by the

floor plate The floor plate is a structure integral to the developing nervous system of vertebrate organisms. Located on the ventral midline of the embryonic neural tube, the floor plate is a specialized glial structure that spans the anteroposterior axis f ...

, and this process is directed by the notochord. Differentiation of neurons in the basal plate is under the influence of the protein Sonic hedgehog released by ventralizing structures, such as the notochord and floor plate. Gray642.png, The basal plate (basal lamina) is separated from the

(alar lamina) by the

(unlabeled).

References

;Bibliography *

External links

Overview at temple.edu
* {{Authority control Embryology of nervous system