The Nervous Systems Of All Organisms Confront Perturbations Ranging From Genetic And Developmental Errors

Among various types of organ systems, the nervous system is one of the most important one in human body. It is responsible for producing, controlling and guiding our thoughts and responses to the world around us according to James W. Pennebaker (2012). During embryological development, the cells that form nervous system are incredibly specialised and work complexly than the cells that form skin or other body parts. Neurosecretory cells are one of the examples of specialised nervous system cells that produce neurosecretions. Neurosecretions are hormones which carry information from sensor cells to target cells and they can be released directly into the bloodstream

Elly Nedivi, an Associate Professor of Neurobiology at the Picower Institute for Learning and Memory, with the help of her colleagues, discovered that a certain type of brain cell can remodel lost connections, or neural pathways. Previously, researchers had found large-scale changes in dendrite-length, but more importantly, they found that this dendrite growth was limited to a specific type of cell: the interneuron. The cortical neurons they studied showed no significant changes. Unlike sensory or motor neurons that perform specialized functions, interneurons are neurons that form connections between other neurons within the brain.

Our focus for this week’s lab was the vertebrate nervous system. The nervous system is composed of two divisions called the central nervous system and the peripheral nervous system. Within these two divisions there are three types of neurons that allow us to recognize changes in our environment and help us to respond accordingly. The three neurons that are found are called sensory neurons, interneurons, and motor neurons.

The nervous system and endocrine systems both work to maintain a constant internal environment, while also being able to respond and adapt to external events (Boundless, 2016).

Neurons are the rudimentary particles of the nervous system, and they are the body’s rapid electrochemical information system. Every single neuron receives signals through its branching dendrites, and conducts signals through its axons. Some of our axons are enclosed in a myelin sheath, which enables faster transmission of the signal. If the combined received signals exceed a certain minimum threshold, the neuron “fires” a signal, transmitting an electrical impulse, also known as the action potential, down its axon by way of a

These rearrangements are integral to the adaptive nature of the brain and crucial to its many functions. However, having a continuous stream of new synapse appearing and modifying the connectivity patterns of a finite space must lead to the removal of some data in order to maintain an efficient system; this means that processes that promote the remodeling of the brain also promote instability within some of the connections and in turn transience. [3]

Cnidarians do not have a central nervous system (no local concentration of nerve cells, no brain), but the anemones simple differentiated nervous system works much the same. Arrangements of nerve cells within a loose network called nerve nets process and respond to stimuli much like a brain would. For example, in response to stimuli, nerve cells emit electrical impulses through the nerve net to all parts of the anemone’s body, causing contractions in the anemone’s muscles. The result is movement.

Using electron microscopy, Bailey and Chen studied the morphological changes seen at the synapse when long-term learning takes place. By assessing habituation and sensitization in Aplysia, they were surprised to find that in animals not exposed to learning situations, only 41% of the varicosities (synaptic knobs) had an active zone, an area with a thicker membrane. Regarding short-term learning, they found no change in these active zones; however, they did fine that only 12% of the vesicles were releasable, as opposed to the normal 30%. When studying the animals with greater sensitization, researchers found that 65% of the varicosities had an active zone, coming from 20 vesicles with an active zone. From this, Bailey and Chen showed that long-term leaning led to morphological differences, occurring just

The nervous system helps maintain homeostasis by controlling and regulating the other parts of the body. A deviation from a normal set point act as a stimulus to a receptor, which sends nerve impulses to a regulating center in the brain. For example, “breathing is involuntary, the nervous system ensures that the body is getting much needed oxygen through breathing the appropriate amount of oxygen.” This shows that the nervous system plays a role in making sure that the breathing patterns of a human stays constant in order to maintain homeostasis. This system is the control center of the human body. The Control center sets the range of value to be maintained and is made up of the brain, spinal cord and nerves. The nervous system is important to the human body because its an organ system in charge of sending messages to and from the brain and spinal cord to and from all parts of the body. What helps send these messages are nerves, one or more bundles of fibers forming part of a system that conveys impulses of sensation, motion, etc, between the brain or spinal cord and other parts of the body. Nerves act as highways to carry signals between the brain and spinal cord and the rest of the body. The Central Nervous system is the complex of nerve tissues that controls the activities of the body, it consists of two parts: the brain and the spinal cord. The brain is arguably the most important organ in the human body. It controls and coordinates actions and reactions, allows us to think and feel enables us to have memories and feelings- all the things that makes us human. Three main parts of the brain is the forebrain, midbrain, hindbrain. The Forebrain consists of the cerebrum, thalamus, and hypothalamus, The Midbrain consists of the tectum and tegmentum, The Hindbrain is made of the cerebrum, pons and medulla, brainstem.

Within the human anatomy, an intricate and complex network of specialised nerve fibres and neurons works in collaboration with the central nervous system and peripheral system, designed to carry out the various actions humans perform every day. The nervous system is also known as the master control unit of the human body, as it operates other major functions such as the circulatory and respiratory systems (Jakab, 2006). It is composed of the central nervous system (CNS) and the peripheral nervous system (PNS). The neurons established within the various sections of the nervous system, is structured with three main parts: a dendrite which is a cluster of branches that operates by receiving information from the

There are two main origin theories on the evolution of the nervous system. These two concepts are monophyly and polygenesis. Monophyly states that, all neurons came from a single ancestry, while polygenesis states that there is more than one independent ancestry of neurons among species. The concept of monophyly is the groundwork of all biology (Moroz, 2009). The lineage of the nervous system present in all animals can be traced back to a common ancestor (Ghysen, 2003).

Chapter two of our textbook explains the cells of the nervous system and nerve impulses. The nervous system consists on two types of cells: neurons and glia. “Neurons receive information and transmit it to other cells” (Kalat 28) . Glia do not transmit information, but they have many different types with many different functions (Kalat 33) . Dendrites and axons both branch off from the neuron. Dendrites receive information from other neurons and axons send the information to other neurons (Kalat 30) . Dendrites and axons “can change their branching patterns as a function of experience, age, and chemical influences” (Kalat 27). Each adult has an estimate of 100 billion neurons in their brain alone (Kalat 28).

According to the article evolution has designed far more than just our eyes, hands, or instincts. The brain itself has been molded by evolution over millions of years in order to address the problems that our ancestors faced, such as, “… understanding and outmaneuvering objects, animals, plants, and other people” (How the Mind Works). The brain can essentially be thought of as a thought computer that is composed of various modules, which each perform specialized functions optimally and have been shaped to do so through natural selection. Through the evolutionary perspective, Psychology is engineering in reverse in that we begin with the whole and then dissect and understand the individual parts the whole consists of. The brain is an incredible device that performs feats that are still impossible for humans to recreate today. It is because of dilemmas faced by things, such as reverse imaging/optics that we still cannot create a robot. The only reason our brains can accomplish reverse imaging is because of having a general schema in place through which all incoming information is processed based upon assumptions that they will follow certain characteristics. For example, the brain assumes that the world is generally made up of flat surfaces of varying color that consist of different textures so that reverse imaging can become possible. This preprogrammed schema is so powerful that we cannot ever choose to be devoid of its illusions, a tv will always seem to

Our neurons consist of a cell body, with one or multiple dendritic branched structures and a long, axon, fiber-like extension. The dendrites primarily receive signals from sensory organs and other neurons. The axon communicates the signal to the dendrites or adjacent nerve cells via the tiny gaps of synapses. The communication across these gaps is enabled by neurotransmitters. In particularly, there are three broad mechanisms in which neural plasticity can occur. These include the anatomical alterations that involve physical changes to neurons, such as axonal sprouting, where axons produce new nerve endings that connect to other pathways in the nervous system; neurochemical changes that can involve the increase or decrease in the production of neurotransmitters; and the metabolic changes which can involve the variation in the rate of nutrients consumed by areas in the brain.

The nervous system is a complex body system that takes years to fully develop and changes main functions throughout one’s life. (Enter Fetal Development Structure Here). Postnatal nervous system development is a mix of fully developing parts of the brain, learning motor skills and natural responses to outer stimuli. By puberty, all parts of the brain and spinal cord are almost fully growth, and the pituitary gland starts releasing FSH and LH to begin the development of the body. After the frontal lobe is at its full maturity level, the brain begins to lose grey matter and white matter, this causes the nervous system to focus on maintaining homeostasis and make decisions based on what is being lost and how do deal with it. Disorders are very prevalent with the nervous system, such as Autism and Epilepsy, and they also occur due to