alar plate

Examples of alar plate in the following topics:

• Embryonic Development of the Brain

  • The neural plate folds outwards to form the neural groove.
  • The anterior (front) part of the neural tube is called the basal plate; the posterior (rear) part is called the alar plate.
  • In the fifth week, the alar plate of the prosencephalon expands to form the cerebral hemispheres (the telencephalon).
  • The basal plate becomes the diencephalon.
  • The rhombencephalon folds posteriorly, which causes its alar plate to flare and form the fourth ventricle of the brain.

• Neurulation

  • This strip is called the neural plate, and it is the origin of the entire nervous system.
  • The neural plate folds outwards to form the neural groove.
  • The anterior (ventral or front) part of the neural tube is called the basal plate; the posterior (dorsal or rear) part is called the alar plate.
  • In general, it entails the cells of the neural plate forming a cord-like structure that migrates inside the embryo and hollows to form the tube.
  • Transverse sections that show the progression of the neural plate into the neural tube.

• Pons

  • The alar plate produces sensory neuroblasts, which will give rise to the solitary nucleus and its special visceral afferent column, the cochlear and vestibular nuclei (which form the special somatic afferent fibers of the vestibulocochlear nerve), the spinal and principal trigeminal nerve nuclei (which form the general somatic afferent column of the trigeminal nerve), and the pontine nuclei, which is involved in motor activity.
  • Basal plate neuroblasts give rise to the abducens nucleus (forms the general somatic efferent fibers), the facial and motor trigeminal nuclei (form the special visceral efferent column), and the superior salivatory nucleus, which forms the general visceral efferent fibers of the facial nerve.

• Medulla Oblongata

  • The final neuroblasts from the alar plate of the neural tube produce the sensory nuclei of the medulla.
  • The basal plate neuroblasts give rise to the motor nuclei.

• Facial Muscles

  • It is split into two sections: alar and transverse.
  • The alar section attaches to the cartilage of the nose and the transverse section to an aponeurosis covering the bridge of the nose.
  • Actions:  The transverse section closes the nostrils and the alar part opens them.

• Cartilaginous Joints: Synchodroses

  • A temporary form of joint called an epiphyseal (growth) plate, is one where the cartilage is converted into bone before adult life.
  • The epiphyseal plate is a hyaline cartilage plate in the metaphysis at each end of a long bone.
  • The epiphyseal plate is found in children and adolescents.
  • In puberty, increasing levels of estrogen, in both females and males, leads to increased apoptosis of chondrocytes in the epiphyseal plate.
  • In adults who have stopped growing, the plate is replaced by an epiphyseal line.

• Development of the Peripheral Nervous System

  • In vertebrates, the first sign of the nervous system is the appearance of a thin strip of cells along the center of the back, called the neural plate.
  • The inner portion of the neural plate (along the midline) is destined to become the central nervous system (CNS), the outer portion the peripheral nervous system (PNS).
  • The sequence of stages from neural plate to neural tube and neural crest is known as neurulation .
  • After gastrulation, neural crest cells are specified at the border of the neural plate and the non-neural ectoderm.
  • During neurulation, the borders of the neural plate, also known as the neural folds, converge at the dorsal midline to form the neural tube.

• Nails

  • The fingernail generally serves two purposes: as a protective plate and enhances sensation of the fingertip.
  • The nail plate is the actual fingernail, composed of translucent keratin.
  • The underneath surface of the nail plate has grooves along the length of the nail that help anchor it to the nail bed.
  • The perioncyhium is the skin that overlies the nail plate on its sides.
  • The hyponychium is the area between the nail plate and the fingertip.

• Peripheral Motor Endings

  • A neuromuscular junction exists between the axon terminal and the motor end plate of a muscle fiber where neurotransmitters are released.
  • A neuromuscular junction is the synapse or junction of the axon terminal of a motor neuron with the motor end plate, as shown in Figures 1 and 2.
  • Acetylcholine diffuses into the synaptic cleft and binds to the nicotinic acetylcholine receptors located on the motor end plate.
  • These receptors open to allow sodium ions to flow in and potassium ions to flow out of the muscle's cytosol, producing a local depolarization of the motor end plate, known as an end-plate potential (EPP).
  • The binding of acetylcholine at the motor end plate leads to intracellular calcium release and interactions between myofibrils to elicit contraction.

• Thoracic Cage: Sternum

  • The sternum or breastbone is a long, flat, bony plate connected to the rib bones via cartilage that forms the anterior section of the rib cage.
  • The sternum, or breastbone, is a long, flat, bony plate that forms the most anterior section of the ribcage.