The Comparison of Nervous Systems in Humans, Cnidarians, Flatworms, and Annelids

The ganglion and the two nerve cords that run along either side of the planaria are connected and are all used in the process of sensing stimuli that occur in the animal’s surrounding. Running back and forth from the organism’s sides are transverse nerve cords; each of these cords connect to the two lateral nerve cords at commissures. By observing the two nerve cords and the many transverse nerve cords, the Dugesia tigrina’s nervous system appears similar to a ladder (Miller 2007).

All organisms in the world have a range of systems and organs in their body. Some organisms may share similar body systems while others have absolutely nothing in common. Several of those organisms include humans, pigs, crayfish, and earthworms. From their mushy, gushy organs to their soft, gentle skin, you may think, “How are humans and pigs possibly alike? Or a crayfish and an earthworm?” In many ways they may not be, but in other ways, they are very much alike. The body systems that will be compared and contrasted of these organisms are the nervous, circulatory, reproductive, muscular, integumentary, digestive, excretory, and skeletal systems.

The worm, crayfish, and the frog have many of the same distinct features as well as some that are not. Throughout the dissection days, i’ve observed many things that relate to the human body system like the digestive system, respiratory, reproduction, etc. But, there are also many things that don’t match with one another. There are many things I can talk about the similarities and differences between all these animals to the human system, but i'll keep this short so it won’t be a whole 7 page essay. I will be talking about mostly about the similar and differences to each one that is compared to the human body system or mostly compared to one another.

The stimuli will cause a specific reaction within the body depending on the signals – these allow the body to perform its functions smoothly and aid in quick reflexes. Different nerves and cells implement their own distinct actions, each which serve their own purpose in the total body operation.

Neurons (also known as neurons, nerve cells and nerve fibers) are electrically excitable and the most important cells in the nervous system that functions to process and transmit information. Neurons have a large number of extensions called dendrites. They often look likes branches or spikes extending out from the cell body. It is primarily the surfaces of the dendrites that receive chemical messages from other neurons.

Neurons, nerve cells, have three basic parts: the cell body, dendrites, and axon. Neurons transmit signals to other nerve cells and throughout the body. They are simple components in the nervous system. The cell body includes the nucleus, which is the control center of the neuron. The dendrite branches off the cell body and receives information. The axon is attached to the cell body and sends information away from the cell body to other cells. When the axon goes through myelination, the axon part of the neuron becomes covered and insulated with fat cells, myelin sheath. This increases the speed and efficiency of information processing in the nervous system. Synapse are gaps between neurons, this is where connections between the axons and dendrites.

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 Central nervous systems include the brain and spinal cord which transfers voluntary nerve impulse to skeletal muscles, skin, muscles, and glands.

The two components of the central nervous system (CNS) are the brain and the spinal cord. Communication between the brain and the spinal cord happens through motor neurons, which are nerve cells that enable motor movement. Each motor neuron is made up of a cell body, which holds all the cell components, dendrites which send information it receives to the cell body, and an axon which sends nerve impulses to the muscle (Porth & Matfin, 2009). As electrical impulses are sent through the motor neuron, it stimulates the muscle fibers in the body to move. This is the process in which motor function happens. Therefore, the basic abilities to breathe, speak, swallow, walk and button a shirt are

Neurons are what make up the nervous system. The nervous system is very complex for all the activities that this system performs. It main function is to communicate. It sends nerve impulses to the muscles (effectors), the muscles receive stimuli and tuned electromechanical signals that are sent to the

The CNS contains the brain and spinal cord. Its main functions include: processing, integrating, and coordinating sensory information and motor instructions. The sensory data conducts information that is being processed from internal and external conditions the body is experiencing. Motor commands regulate and control peripheral organs (skeletal muscles). The brain functions under memory, emotions, learning, and intelligence. The PNS consist of the neural tissue found outside of the CNS. It functions in sending data to the CNS which motor commands are than carried out to the peripheral tissues/systems. Multiple nerve fibers send sensory data and motor commands in the PNS. The nerves that assist with transmitting data include the cranial nerves and spinal nerve. However, the PNS can be divided into afferent (to bring in) and efferent (to bring out) divisions of transferring data. The afferent division functions in bringing in sensory data to the CNS. Sensory structures are receptors that detect internal/external environmental change and adjusting accordingly. The efferent division functions in carrying out motor commands from the CNS to glands, muscles, and adipose tissue. The efferent division contains somatic

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

Neurons are information- processing units in the central nervous system that receive and transmit information. It is made up of an axon, dendrites and a cell body. The nucleus and cytoplasm are contained in the cell body. The axon starts from the cell body, dividing into smaller branches and then ends at the nerve terminals. The dendrites also branch from the cell body, receiving information from the other neurons. Axons from other neurons forms

The nervous system is made up of basic units called neurons. The main role of the neurons is to receive, integrate and transmit information throughout the body. There are some neuroglial cells found in nervous system aswell which provide support to the neurons by giving protection and nourishment Neurons have nerve processes that looks like finger like projections extended from the nerve cell body. They also contain axons and dendrites which enable them to transmit signals throughout the body. Normally, axon carry signals away from the cell body and dendrites carry signals toward the cell body according to Regina Bailey (2013). Neurons have three different shapes: bipolar, unipolar and multipolar where bipolar has two neuronal processes coming out of the cell body, unipolar has only one neuronal process coming out of the cell body and multipolar has many neuronal processes coming out of the cell body.

Individual body functions with the nervous system. The nervous system is divided into two parts, central nervous system and the peripheral nervous system. The central nervous system consists of brain and spinal cord while the peripheral nervous system consists of the nerves, such as cranial nerves. The cranial nerves job is to connect the central nervous system to the different types of organs in the body. Our neurons consist of cells which hold the genetic information needed to make protein. Dendrites receive impulses from other cells at the synapses and transmit them to the cell body. Axons carry outgoing information to target cells. Neuron has only one axon that includes Axon Hillock. Axon Hillock is the originate place for action potential; Axon collaterals are the branches of axon; Axon terminals which are the sites of neurotransmitter release myelin sheath. The body neuron usually generates an electrical signal and this result in the release of neurotransmitter. The neurotransmitter purpose is to serve as a chemical messenger that enables cell communication among other cells.