The dendrite in these neurons also shows extensive branching soon after leaving the cell body. Bipolar Neurons: These neurons have a single axon and a single dendrite.Any neuron having two or more dendrites with one axon is included in this category. Most of the neurons in the human body are multiple neurons. The dendrites show different varieties of branching or arborization based on the location of neurons. Multipolar Neurons: These neurons have multiple dendrites and a single axon.The shape and orientation of dendrites in these neurons are discussed below. Types of Neuronsīased on the number of cellular processes, neurons are divided into the following types. However, now it is a known fact that neural summation of action potentials can take place in the dendrites. Initially, it was thought that the action potential generated simultaneously at the dendrites did not add or cancel each other. Soon, they were recognized to be an input component of the neurons. The electrical activity in the dendrites was recorded in 1930. Later, they were discovered to be a part of synapses by which nerve impulse travels from one neuron to the other. The term dendrites were first introduced and used in 1889. It was thought that the protoplasmic projections played a nutritive role in the functioning of neurons. The function of these projections was not known at that time. They were named protoplasmic projections by Golgi. Historical Factsĭendrites were first studied by Golgi in 1873 who proposed them to be the projections of protoplasm found in the neurons. These structures are considered to play an important role in neural plasticity for adaptation, learning, and memory. These serve as the initial sites for the processing of information received by the synapse. They are composed of actin filaments and are highly plastic.ĭendritic spines are abundantly present in the neurons of the cerebral cortex. These structures are visible on dendrites upon silver staining. Most of the synapses impinge on these dendritic spines. They occur at regular intervals along the length of dendrites. These are the short blunt structures associated with dendrites. Unlike axons, they have a variable diameter or thickness that decreases as the branching proceeds. As the dendrites branch, their thickness goes on decreasing. The branching pattern of dendrites is also different among different neurons. They show multiple branching or arborization. The size and thickness of dendrites vary among different types of neurons. The membrane of dendrites has abundant receptors where the neurotransmitters released at the synapse attach and initiate an action potential in the neuron. It is rich in cytoskeletal components that provide structural support to the dendrites. The cytoplasm of dendrites has the same composition as found in the cell body of neurons. They have varying shapes and structures among different neurons found in the central as well as the peripheral nervous system. Structure and Historyĭendrites are the cytoplasmic projections of neurons. We will also study different functions performed by dendrites as well as their clinical importance. In this article, we will talk about the structure of dendrites, their embryologic development, their metabolism, and different scheme of dendrites arborization. Dendrites are the cellular processes that carry nerve impulses towards the cell bodies of neurons. The cellular processes of neurons are divided into two categories based on the direction of nerve impulses. Nerve impulses travel along with these cellular processes of the neurons. These neurons have a cell body with radiating cellular processes. It is comprised of millions of neurons that are responsible for carrying messages in the form of nerve impulses from one part of the body to the other. What happens when dendrites are damaged?Ĭoordination among the different organs and organ systems in the body of animals is brought about by the nervous system.What is the difference between axons and dendrites?.Factors Controlling Dendritic Development.
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