A cross section of the spinal cord reveals white matter arranged around a butterfly-shaped area of gray matter. The white matter consists of myelinated fibres, or axons, that form nerve tracts ascending to and descending from the brain. The white matter is grouped into discrete sectors called funiculi.
What are the 7 major structures of the spinal cord?
Spinal Column
It consists of seven Cervical Vertebrae, twelve Thoracic Vertebrae, five Lumbar Vertebrae, five Sacral and four Coccygeal Vertebrae, The five sacral vertebrae are fused in adults to form the sacrum, and the four coccygeal vertebrae are fused to form the coccyx.
What are the 5 divisions of the spinal cord?
Sections. The spine is composed of 33 bones, called vertebrae, divided into five sections: the cervical, thoracic, and lumbar spine sections, and the sacrum and coccyx bones. The cervical section of the spine is made up of the top seven vertebrae in the spine, C1 to C7, and is connected to the base of the skull.
What are neurones?
Neurons are information messengers. They use electrical impulses and chemical signals to transmit information between different areas of the brain, and between the brain and the rest of the nervous system.
What is dura?
Dura: The outermost, toughest, and most fibrous of the three membranes (meninges) covering the brain and the spinal cord. Dura is short for dura mater (from the Latin for hard mother). Also called the pachymeninx (singular) or pachymeniges (plural). Epidural means outside the dura.
What are the 31 segments of the spinal cord?
The spinal cord is located in the vertebral foramen and is made up of 31 segments: 8 cervical, 12 thoracic, 5 lumbar, 5 sacral and 1 coccygeal. A pair of spinal nerves leaves each segment of the spinal cord.
What is grey matter?
Grey matter (or gray matter) makes up the outermost layer of the brain and is pinkish grey in tone, hence the name grey matter. It gets its grey tone from the high concentration of neuronal cell bodies in contains. Grey matter also contains unmyelinated axons.
What is the end of the spinal cord called?
Many spinal nerves extend beyond the conus medullaris (the end of the spinal cord) to form a bundle of nerves called the cauda equina.
What are the 6 types of spinal nerves?
Spinal Nerves: Cervical, Thoracic, Lumbar, Sacral, Coccyxgeal.
What bones protect the spinal cord?
The spinal cord is protected by bones, discs, ligaments, and muscles. The spine is made of 33 bones called vertebrae. The spinal cord passes through a hole in the center (called the spinal canal) of each vertebra. Between the vertebrae there are discs that act as cushions, or shock absorbers for the spine.
What is the space between a dendrite and an axon called?
The space between the dendrites of one neuron and the axon of another neuron is called the synapse.
What is the lower section of the spine called?
The bottom of the spine is called the sacrum. It is made up of several vertebral bodies usually fused together as one. The remaining small bones or ossicles below the sacrum are also fused together and called the tailbone or coccyx.
What are the 26 bones of the spine called?
It consists of 26 bones called vertebrae. The bottom two vertebrae consist of fused bones, five in the upper one and four in the lower one. Each vertebra has a strong, stubby section that supports your weight, and a hole for the spinal cord to pass through.
Which of the following sections of the spinal column have five vertebrae?
1 Answer. Both the lumbar and the sacral spinal section have 5 bones.
What does a dendrite do?
Dendrite – The receiving part of the neuron. Dendrites receive synaptic inputs from axons, with the sum total of dendritic inputs determining whether the neuron will fire an action potential. Spine – The small protrusions found on dendrites that are, for many synapses, the postsynaptic contact site.
What is the function of dendrite?
Dendrites are appendages that are designed to receive communications from other cells. They resemble a tree-like structure, forming projections that become stimulated by other neurons and conduct the electrochemical charge to the cell body (or, more rarely, directly to the axons).
What is Neuroglial cell?
Neuroglia are a large class of neural cells of ectodermal (astroglia, oligodendroglia, and peripheral glial cells) and mesodermal (microglia) origin. Neuroglial cells provide homeostatic support, protection, and defense to the nervous tissue.
