Signature Assignment

Signature Assignment

Question 1

The first arrow in the patient penetrated the pleural cavity. This is a serous membrane covering the walls of various organs of the abdominopelvic cavities and the thoracic cavities. They are essential for secreting lubricants which reduce the amount of friction from excessive muscle movement within the body (D’Arienzo et al., 2016).

Question 2

Typically, the autonomic nervous system is paramount in controlling involuntary functions within the body. These automatic actions involve the heartbeat and breathing. Therefore, autonomic dysfunction can adversely affect heart rate and blood pressure (Glynos et al., 2015).  As a result of the arrow injury and attack, the patients’ pulse will be rapid and low as a result of shock.

Additionally, the patient’s blood pressure will also reduce. However, the patient’s body temperature is expected to decrease because the blood will be shunted towards critical organs in the body (Bassi et al., 2015).  The patient’s respiratory rate of the patient will increase while at the same time remaining shallow.

Question 3

The trajectory of the first arrow to enter the patient can be described as posterosuperior and falling along the axial plane. However, from a posterior and anterior angle, the organs expected to be affected will be both the posterior and anterior skin (Duan et al., 2015). Additionally, the lungs and the heart are the most crucial organs that will be affected by the arrow. Also, since the second injury is located in the posterior triangle within the neck, contents of the posterior triangle situated within the neck will also be affected by the arrow. Its contents include; supraclavicular lymph nodes, brachial plexus, spinal accessory nerve and occipital lymph node (Duan et al., 2015).

Question 4

The cardiovascular system is composed of different tissues and organs functioning as a unit.  The system has three necessary functions, which include; removal of toxic wastes from the body, transport of oxygen, hormones, and nutrients to different parts of the body (Fritz et al., 2018). However, when Hematocrit levels are on the rise above optimum, the result is blood thickening making it impossible for the heart to perform its duty to pump blood to the rest of the body. This can easily lead to a heart attack.  On the other hand, Hemoglobin can be described as a red protein essential in the transport of oxygen in vertebrates. Blood loss can cause a condition called anemia when not treated appropriately.

Question 5

Neuromuscular Effects of the Second Arrow

Based on the physical examination done on the patient, the second arrow pierced through the posterior cervical triangle. Apart from pain resulting from the piercing of the patient’s muscles, other neuromuscular effects might have also resulted from the injury. First of all, the suprascapular nerve passes through this region and its function is to innervate two rotator curve muscles of the shoulder which include supraspinatus and infraspinatus (D’Arienzo et al., 2016). The supraspinatus performs different functions on the arm such as enabling abduction, flection, and stabilizing of the humerus in the glenoid fossa to prevent dislocation during movement. Therefore, injury to the suprascapular nerve affects the patient’s ability to abduct and flex his arm (Fritz, Katthagen, Boykin, & Millett, 2018). As a result, the patient will feel trauma while trying to abduct or flex the arm. Also, it will be difficult for the patient to throw thing using the affected arm.  Besides, the infraspinatus controls the external rotation of the arm, and its injury will also affect about 40-50% of the throwing ability since the external muscles will not be stable to necessitate the process.

Besides, the accessory nerve passes through the posterior cervical triangle and it also likely to be affected by the arrow piercing through the region (Duan et al., 2015). Since the accessory nerve is responsible for the motor function of the sternocleidomastoid muscle which extends to the shoulder and the upper back, its dysfunction can affect the patient’s shoulder performance. For instance, the patient may find it difficult sleeping on the back, bending, or doing any strenuous activity. In essence, the patient may not be able to perform activities of daily living since the shoulder, and the upper back is among the integral parts that control human performance.

Components of the Neuromuscular Junction

A neuromuscular junction refers to the connection between the nerve fiber endings and the middle of muscle fibers. It is made up of several components which substantiate its functions in the human body. The first component is the synaptic knob which refers to the tip of nerve fibers which is usually dilated (Jones et al., 2016). It also contains synaptic vesicles. Secondly, the neuromuscular junction is made up of a synaptic cleft which is a gap that exists between the synaptic knob and the sarcolemma. It is about 60 to 100 nm. As mentioned earlier, synaptic vesicles are also contained in the synaptic knob of the neuromuscular junction. They contain acetylcholine which is a neurotransmitter that is produced by somatic motor fibers. Acetylcholine stimulates skeletal muscle fibers to release energy.

Furthermore, Acetylcholine fibers have their own receptors which are contained in the junctional folds. Junctional folds include the folds in the sarcolemma that covers skeletal muscles. As such, acetylcholine binds to the acetylcholine receptors so as to carry out its function. Another component of the neuromuscular junction is acetylcholinesterase. This is an enzyme found in the sarcolemma and also in the basal lamina of the muscle fibers found in the synaptic region. The enzymes are responsible for the degradation of acetylcholine and also stopping muscle fiber stimulation when there is no need to release more energy.  The different components of the neuromuscular junction work together to accomplish its function which is the transmission of signals from motor neurons to the involved skeletal muscles (Hepple, & Rice, 2016). As a result, muscle contraction and movement are enhanced, and this enables human beings to perform different functions.


Question 6

Identify and Describe Labelled Tissues in Slide 2

            In slide 2 three tissues are labeled whereby number 1 is the cartilage tissue, number 2 is the smooth muscle, and number 3 is the mucosa. First of all the trachea is made up of about fifteen to twenty rings of cartilage tissue made of hyaline tissue that contains collagen. Collagen keeps the rings of cartilage together. Besides, the rings of cartilage are made of strong connective tissues that enable them to keep the trachea open at all time for continuous breathing. The cartilage is able to perform the function mentioned above because it is made up of cells called chondrocytes. The cells release extracellular matrix which is made of collagen, elastin fibers, and proteoglycan that keep it strong. Also, the cartilage tissue is made up of blood vessels that supply it with blood.

The second tissue is composed of smooth muscles which are found between the rings of cartilage. The smooth muscle is made up of fibers which are elastic to allow the tracheal wall to adjust inwards and outwards during breathing. It also contains blood vessels that supply its tissues with blood. It is also known that the smooth muscle is made of involuntary non-striated muscles. More so, it is divided into the single unit and the multiunit.

The third tissue comprises of the mucosa which is the innermost layer. It is made up of ciliated pseudostratified columnar epithelium. The epithelium contains numerous goblets that release mucus which keeps the tracheal walls moist to enhance continuous gaseous exchange. Also, the produced mucus coats the tracheal wall so that dust and other solid substances can be trapped before reaching the lung cavity. Furthermore, the mucosa contains a submucosa which is made up of the areolar connective tissue and blood vessels that supply the mucosa with blood.


How Injuries will affect the Areas labeled in Slide 2

            First of all the cartilage is made up of extracellular matrix which consists of collagen and proteoglycans that keep its rings strong. As such, the cartilage keeps the walls of the trachea open for continuous breathing (Glynos et al., 2015). However, the injuries from the arrow piercing will lead to the breaking of the cartilage rings. As a result, the tracheal wall may bulge inwards since the collagen fibers can no longer support them. Since breathing is necessitated by the open wall of the trachea, it will be impaired in this case. Besides, impaired breathing causes an insufficient supply of oxygen in the blood, and the may be at risk of hypoxemia and hypoxia due to the poor oxygen supply.

Also, tracheal smooth muscle can be affected by the injury resulting from arrow piercing. As shown before, smooth muscles are made up of involuntary non-striated muscles which can contract and expand depending on different triggers. They also contribute to the openness of the trachea. Therefore, injury to the smooth muscle tissue will affect the airway since the walls will not be able to contract and relax to allow air to pass through it. Although smooth muscles regenerate after dying, the abrupt death of tracheal smooth muscles due to injury can affect normal breathing before the regeneration process ends. As a result, the patient may suffer from oxygen hunger unless an alternative gaseous exchange mechanism is put in place.

Lastly, injury to the tracheal mucosa also has outstanding outcomes for the health of the patient. Being the innermost layer of the tracheal walls, it needs to be free from any injury to ensure that gaseous exchange is continuous. However, any injury to it may affect the whole breathing process. Firstly, injury to the mucosa caused by piercing leads to inflammation of the mucosal walls (Bassi et al., 2015). Some effects of inflammation include swelling, pain, and infection due to the accumulation of mucus at the affected areas. As a result, the gaseous exchange will be impaired since the airway is narrowed and the patient cannot breathe comfortably due to the pain resulting from the affected area. Furthermore, injury to the tracheal mucosa leads to the destruction of goblet cells that light its walls. In this regard, dust particles and other contaminants will move to the lungs due to inadequate mucus production to trap them. The accumulation of such particles in the lungs may result in pulmonary infections such as pneumonia which is a high risk to the health of patients.

In essence, injuries affecting the trachea have been confirmed to cause a high mortality rate with about 30% being at high risk of death. General symptoms presented by the patient may include difficulty in breathing, hoarseness in the voice, abnormal breathing, and coughing. In that case, the patient should be managed immediately by removing the blocking item through surgical intervention. After that, other symptoms can be managed to ensure that the patient is safe. Regarding the patient with an injury with arrow piercing, the arrow should be removed surgically and the influence of general anesthesia before attempting any other treatment approach.

Types of Tissues

  1. Cartilage tissue- hyaline tissue, collagen
  2. Smooth muscle tissue- Single unit and multiunit
  3. Mucosa- Submucosa





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D’Arienzo, M., Peri, G., Valentino, B., Conti, A., D’Arienzo, A., & Peri, D. (2016). Anatomy of the Cervical Spine. In the Cervical Spine (pp. 1-9). Springer, Cham.

Duan, Y., Wang, H. H., Jin, A. M., Zhang, L., Min, S. X., Liu, C. L., … & Shu, X. Q. (2015). Finite element analysis of posterior cervical fixation. Orthopaedics & Traumatology: Surgery & Research, 101(1), 23-29.

Fritz, E. M., Katthagen, J. C., Boykin, R. E., & Millett, P. J. (2018). Suprascapular Nerve Release with Rotator Cuff Tears. In Rotator Cuff Injuries (pp. 313-326). Springer, Cham.

Glynos, C., Toumpanakis, D., Loverdos, K., Karavana, V., Zhou, Z., Magkou, C., … & Topouzis, S. (2015). Guanylyl cyclase activation reverses resistive breathing–induced lung injury and inflammation. American journal of respiratory cell and molecular biology, 52(6), 762-771.

Hepple, R. T., & Rice, C. L. (2016). Innervation and neuromuscular control in aging skeletal muscle. The Journal of physiology, 594(8), 1965-1978.

Jones, R. A., Reich, C. D., Dissanayake, K. N., Kristmundsdottir, F., Findlater, G. S., Ribchester, R. R., … & Gillingwater, T. H. (2016). NMJ-morph reveals principal components of synaptic morphology influencing structure-function relationships at the neuromuscular junction. Open biology, 6(12), 160240.