The cell body, also called the soma, contains the nucleus, cytoplasm, and other organelles. It manages the metabolic activity of the neuron. The axon is a thin cytoplasmic projection that extends from the cell body. It transmits impulses from the cell body to another nearby neuron. At its end, it may branch off in order to transmit impulses to dendrites.
This depolarizes that axon section, causing another axon gate to open, and then another, like a line of dominos. During the resting pause, the neuron pumps the positively charged sodium ions back outside. Then it can fire again. These transmissions occur electrically and chemically. Electrically, the neuron is directly neighboring to other neurons.
RSQC2 Worksheet Directions: Fill in the blanks below. Identify the following parts of a neuron (need an image): (dendrites, axon, terminal buttons, myelin sheath) Dendrites: The cluster of fibers at one end of the cell body that receive messages from other neurons. Axon: The slim, tube-like extension of the cell body that carries messages from the dendrites to other neurons. Terminal buttons: The small bulges at the end of the axon which send messages to other neurons. Myelin sheath: A protective coating of fat and protein that insulates the axon.
It runs down the center of the protective spinal column which runs from the neck to the lower back. The nerves in the spinal cord 8. transmit information from body organs and external stimuli to the brain. It sends information from the Cerebellum Is the area of areas of the body. These transmissions travel in two pathways one
If the cell body dies, the neuron dies. * Axon - This long, cable-like projection of the cell carries the electrochemical message (nerve impulse or action potential) along the length of the cell. * Depending upon the type of neuron, axons can be covered with a thin layer of myelin, like an insulated electrical wire. Myelin is made of fat, and it helps to speed transmission of a nerve impulse down a long axon. Myelinated neurons are typically found in the peripheral nerves (sensory and motor neurons), while non-myelinated neurons are found in the brain and spinal cord.
The hippocampus on the other side is responsible for the production of corticosteroids (chemicals that produce physiological responses to stimuli). How the mind creates memories is controlled by the hippocampus. So as to work efficiently, the amygdala and the hippocampus rely on each other greatly. The amygdala regulates the responses to stimuli and the hippocampus uses these responses in the formation of both short-term and long-term memories. Damage to the amygdala or hippocampus causes loss of emotions and memory respectively.
There are two main processes that are highly believed to be the main contributor to dementia development, the formation of the amyloid protein and cholinergic transmission (neurotransmitter Acetylcholine (Ach)). The amyloid cascade hypothesis refers to the disposition of the amyloid-β protein in the brain (loss of cholinergic neurons occur in the basal forebrain). Mutations then occur resulting in the gene amyloid precursor protein (APP) developing in the brain, and creating an imbalance between the amyloid- β production and removal; resulting in a cytotoxic build up of the amyloid protein, causing neuritic plaques and neurofibrillary tangles in the brain, which are present in the brain of AD patients (Karran, Mercken and Strooper, 2011). Support for this hypothesis arises from the knowledge that transgenic mice, which express the mutant human gene APP, show the changes most recognizable with AD (plaques and the memory deficits)(Selkoe, 2005). Cholinergic transmission can be defined as the physiological process that operates the neurotransmitter acetylcholine (ACh) to communicate between cells (Wess, 1993).
The brain stem (midbrain pons and medulla oblongata) Controls involuntary reflex actions The cerebellum Maintains posture and co-ordinates movement. It received messages from the cerebrum and muscles and joints The diencephalon (includes the thalamus and hypothalamus Controls homeostatic mechanisms and the autonomic nervous system The cerebrum The largest part of the brain, divided into three areas that control movement, interpret sensory impulses and control of thought, memory, emotions and personality traits Nerves Nerves are compiled of neurons or nerve cells. These cells can vary in structure this depends on two different things: 1. Where they are 2. What they do But all cells have cell body’s containing the nucleus.