1. In the human body, the spinal cord includes both white matter and gray matter. The grey matter, which consists of neuronal cell bodies and dendrites of neurons, neuroglia and unmyelinated axons, is the major component. The white matter contains myelinated axons that create the nerve tracts. “The nerve tracts of the spinal cord provide a two-way communication system between the brain and body parts outside the nervous system” (Shier, Butler, & Lewis, 2003). As we know, there are 31 pairs of spinal nerves, and each pair has a ventral root and a dorsal root. The dorsal root plays an important part in transmitting sensory information and forming the afferent sensory root of spinal nerve. The ventral root contents axons of motor neurons and also carries motor impulses to effector organs. Those dorsal and ventral roots come together to form spinal nerves, which carry sensory and motor neurons …show more content…
“Reflexes are automatic subconscious responses to change within or outside the body. They help maintain homeostasis by controlling many voluntary processes, such as heart rate, breathing rate, blood pressure, and digestion. Reflexes also carry out the automatic actions of swallowing, sneezing, coughing, and vomiting” (Shier, Butler, & Lewis, 2003). The reflex that integrated by the spinal cord is called spinal reflex. Spinal reflex might be modulated by higher input from the brain; however, it is able to occur without that input. A reflect arc is a neural pathway which controls a reflex action. In the book “Medical and Advanced Surgical Management of Pelvic Floor Disorders”, Cheryl B. Iglesia states:
The 5 components of the reflex arc are (1) receptors of the clitoral complex and vulva, (2) somatic afferents of the pudendal nerves including the dorsal nerve of the clitoris and the perineal branches, (3) spinal cord nerve roots S2-S4, (4) visceral parasympathetic efferent fibers, and (5) the end organ of erectile tissue: clitoral complex, subbulbar, and urethral glands.
On July 12th 2005, Heather Tice’s life changed forever. Heather was in the passenger seat of a car driving down a steep hill with her seatbelt unbuckled. The next thing she knew she was laying on the ground, covered in blood, unable to feel her own legs. Heather would later find out that she had received an injury to the C7 section of her spinal cord, which is located in the neck. Heather’s injury was incomplete, so despite the height of the injury she retains the use of her upper body (Car accident causes).
Firstly, there is various of sensing activities as in seeing and hearing as in a sense of understanding of what is seen and heard. Secondly the sense of feeling in numerous parts of the body from the head to the toes. The ability to recall past events, the sophisticated emotions and the thinking process. The cerebellum acts as a physiological microcomputer which intercepts various sensory and motor nerves to smooth out what would otherwise be jerky muscle motions. The medulla controls the elementary functions responsible for life, such as breathing, cardiac rate and kidney functions. The medulla contains numerous of timing mechanisms as well as other interconnections that control swallowing and salivations.
Dendrites are located on either one or both ends of a cell.The peripheral nervous system then takes the sensory information from the outside and sends the messages by virtue of neurotransmitters. Neurotransmitters are chemicals that relay signals through the neural pathways of the spinal cord. The neurotransmitter chemicals are held by tiny membranous sacs located in the synaptic terminals. Synaptic terminals are located at the ends of nerve cells. The release of neurotransmitters from their sacs is stimulated once the electrical nerve impulse has finished travelling along a neuron and reaches the synaptic terminal. Afterward, neurotransmitters travel across synapses thus stimulating the production of an electrical charge that carries the nerve impulse onward. Synapses are junctions between neighboring neurons. This procedure is reiterated until either muscle movement occurs or the brain picks up on a sensory reaction. During this process, messages are being transmitted from one part of the body onto the next. The peripheral and central nervous system are two crucial subdivisions of the nervous system. The brain and spinal cord make up the central nervous
Based on the findings presented, Dr. Green made the correct diagnosis in predicting that this gentleman had a spinal cord injury.
The testes are the primary reproductive organs in the male; they are responsible for the production of sperm. The testes are responsible for the production of testosterone, and are almost nonexistent prior to puberty. Testosterone affects vary to the sound of your voice to hair baldness. The epididymis is a firm structure that consists of three parts, sperm that passes through the epididymis after they are formed. The male urethra is approximately 18-20 cm long. The urethra allows the passage of both urine and sperm. There are two main parts of the penis; the root and body. The three main parts of the root of the penis are, the midline bulb, and the left and right crura on either side of the bulb. While the body is formed by three cylindrical masses of erectile tissue, they are the corpus spongiosum in the midline, and the two-corpus cavernosa on either side. The urethra leaves the head of the penis at the end of the corpus spongiosum.
The spinal cord is a major channel in the body where motor and sensory information travels from the brain to the body. It has white matter that surrounds a central gray matter. The gray matter is where most of the neuronal cells are located. Injury to the spinal cord will affect the conduction of information across any part of the spinal cord where the damage is located (Maynard et al., 1997). This will often result in permanent disability of a certain muscle or region of the body (Meletis et al., 2008) and a loss of tissue where the damage is located (Peng et al., 2009). As of now, there is no treatment for spinal cord injury expect for steroids. All steroids can do is provide protect of the spinal cord from secondary injury for specific patients (Peng et al., 2009).
Peripheral and central mechanisms involving nerve lesions and their input are substantial when perceiving phantom pain. Due to the impairment of peripheral nerves in the process of amputation, regenerative sprouting of damaged axons occurs and the activity rate of inflamed C-fibres and demyelinated A-fibres spontaneously increases (Flor, 2002). As a consequence of this nerve injury, a neuroma, which is a mass of pruned and tangled axons, may form in the residual limb producing abnormal (ectopic) activity (Katz, 1992). Flor, Nikolajsen and Jenson (2006) proposed that ectopic discharge from a neuroma in the stump illustrates abnormal afferent input to the spinal cord, which is a possible mechanism for unpro...
The myelin sheath is a fatty substance that surrounds the axons of the nerves and provides protection. It allows messages to be sent rapidly and accurately to the axons from long distances (Serono, 2010). The axons are the part of the nervous system that allows electrical transmission of signals throughout the brain and spinal cord. Without these electrical transmissions, the body would not be able to function properly (Serono, 2010).
In each zone, impulses and reflexes travel until they reach nerve endings in the feet and the hands. These zones are believed to be meridians along which energy flows. Placing pressure on the nerve endings in the hands and the feet will affect the organs found in that particular zone (http://www.reflexology.org/aor/refinfo/healart.htm). As well as longitudinal zones throughout the body, there are also cross-reflex points. These cross-reflex points are corresponding points on the opposite side of the body which can be useful in administering reflexology treatment when pressure is not able to be placed on the reflex point....
The sciatic nerve is formed from the lower segments of the spinal cord; it is made up from
Rectus, and External and Internal Obliques flex the spine. Transversus aids in respiration and helps to compress the abdominal cavity to help support the spine in neutral. 4. How does the breath relate to flexion and extension of the spine?
Men and women sexually go through a cycle. This cycle is known as the sexual response cycle. The sexual response cycle is made up of four different phases, the excitement, plateau, orgasm, and resolution phases. The cycle is also categorized in two ways, vasocongestion and myotonia. Vasocongestion is where swelling occurs because blood rushes to certain areas of the body such as earlobes, for women to the opening of the vaginal area, and for men around the testes, it also causes the erection of the penis. Myotonia is what causes hands and feet to spasm, affects the face, and the involuntary movements of orgasm, these occur because the muscles are tightening creating these movements and spasms to occur. (Nevid & Ruthus, 2005).
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 receptor and neurons and transferring nerve impulses to the cell body; furthermore, a cell body is composed of a nucleus, that works to provide energy and nutrients for the neuron; lastly is an axon, electrically conducted by the myelin sheath, the axon is a pathway nerve impulses pass through from the cell body. In addition, this is the process in which nerve impulses travel by to be able to access the rest of the system (Core Science, 2010). The correct function of the nervous system is vital to the daily survival of an individual, as it obtains a significant role in the control and co-ordination of the human body. Furthermore, if a situation occurs where the nervous system dysfunctions or develops a disease (such as multiple sclerosis), it would in that case threaten the current status of one’s health and cause havoc in the system.
Spinal cord injuries can range from minor, meaning the injured will recover, to very severe injuries that can cause significant damage to someone’s body and self-esteem. Approximately 12,000 people per year experience spinal cord injuries in the United States. 50% of all spinal cord injuries occur between the ages of 16 and 30 and 80% of all spinal cord injuries happen to males. The most common accidents that cause spinal cord injuries are motor vehicle accidents followed by falls, violence and then sports. There are two major types of spinal cord injuries, complete spinal cord injury and incomplete spinal cord injury. Spinal cord injuries can also cause other complications including respiratory, bladder control, skin sensation, circulation problems, muscle tone, sexual health, pain, depression, scoliosis, UTI and spasticity. Complete spinal cord injuries occur when one loses complete feeling and sensation typically resulting in paralysis below the injury. Incomplete spinal cord injuries mean there is still some feeling and movement below the injury site. One can experience different types of incomplete spinal cord injuries including anterior cord syndrome, central cord syndrome, brown-sequard syndrome, nerve cell injuries and spinal contusions. Currently there is no cure for spinal cord injuries. Causes of SCI:
A reflex pathway, or a reflex arc, is a neural pathway that is involved in the activation of a reflex. Reflexes are reactions that respond to stimuli. They usually happen without the sensory neurons having to pass directly through the brain. Therefore, reflexes are called involuntary reactions since they happen without a command. This allows the reflex action to occur quickly because the electrical signal can be sent to the spinal cord immediately without needing to go through the brain. The brain receives sensory input as the action occurs, but not before. The human body has lots of reflex pathways. However, if a disruption occurs in these pathways, the person most likely has a certain kind of neurological disorder that will make the person