Biology essay questions

Each essay question is worth 20 points. Response should be at least 150 words long. Sentences should be well developed, show logical and independent critical thinking, understanding of the concepts and their application to provided case studies/scenarios. Answers should be written in your own words.

 

1. While working at an excavation, an archeologist found several small skull bones. She examines the frontal, parietal, and occipital bones and concludes that the skull belonged to a child not even one year old. How can she tell the child’s age from examining the bones? Explain the importance of her finding in relationship to the infant’s postnatal development.

 

2. Michael is a thirty year old salesman who spends approximately 4 days each week traveling to visit with customers in his region. During his routine physical he casually mentions to his physician that he seems to be sweating more profusely than normal and most rooms that once were comfortable are now too “hot”. Michael also reports that he seems to be losing weight even though his appetite has increased. He also complains that he has a shortened attention span and that he always wants to be moving around. Despite the fact that he feels fatigued, Michael claims to have difficulty sleeping and seems to have more frequent bowel movements, occasionally accompanied by diarrhea. The physician checks Michael’s medical history and finds that indeed he has lost 15 pounds since his last physical.

 

Results of Michael’s physical examination and tests performed by endocrinologist concluded that Michael had Grave’s disease, a form of hyperthyroidism believed to be autoimmune in nature. Michael was presented with a number of possible treatment options. After considering all the options, especially the possible effects of radiation on gamete development, Michael chose surgical removal of the thyroid gland. Following successful surgery, Michael was prescribed synthetic thyroid hormone to ensure that his body was receiving adequate thyroid hormone and told to return within 2 months for a follow-up evaluation of circulating thyroid hormone concentrations. He was also cautioned to carefully monitor his calcium intake.

 

a. Thyroid hormones exert their effects on cells in a manner similar to steroid hormones; describe the mechanism of action of thyroid hormones.

 

b. Why would an imbalance in thyroid hormones have such widespread effects on the body?

 

3. Charlie is badly burned in a fireworks accident on the Fourth of July. When he reaches the emergency room, the examining physician determines the severity of the incident as a third-degree burn. What therapeutic measures is the physician likely to recommend? What are the major concerns with third-degree burns? Are third-degree burns more or less painful than the second-degree burns? Explain.

 

4. E.M.S. went to bed about 11 PM after a busy evening of entertaining friends and family. He was awakened at 2 AM with chest pain that radiated to his left shoulder, arm and fingers. His son took him to the emergency room, where he was immediately given oxygen by mask and nitroglycerin. His chest pain was relieved in about 39 minutes. An ECG revealed evidence of myocardial ischemia but no evidence of a myocardial infarction. He was admitted to the cardiac intensive unit for further evaluation.

 

a. What’s the most likely cause of the pain (what’s the name of the condition and what causes it)?

 

b. What kind of medication is nitroglycerin and why does it help to relieve the pain? What are other treatment options for this condition?

 

c. Define the underlined terms.

5. Until recently, 6-year-old Billie had no apparent health problems. About 1 week ago, she started to lose weight despite a healthy appetite. She urinated frequently and complained of being tired. Her mom noticed that she was very thirsty and was getting up in the middle of the night to urinate. On examination, her blood sugar was elevated. She was diagnosed with type 1 (juvenile-onset) diabetes mellitus.

 

a. Which homeostatic mechanism is not properly functioning?

 

b. Explain the physiology of this disease, what’s going wrong? Be specific.

 

c. What can happen if the diabetes is not controlled?

6. Keith is a college student. He is extremely busy studying and working part-time. Keith sleeps in late and therefore does not take time for breakfast. He rushes off to class. At lunch he has time for only French fries. When he gets home from school, he eats canned corn (only corn, nothing else) and washes it down with water. Then, he goes to work, only to start the same routine the next day.

 

When Keith is confronted about his poor diet, he responds, “The French fries are a good source of carbohydrates. Since they are fried in oil, I get my daily requirement of fat. At supper time, I eat corn and it has a lot of amino acids in it.” You, a medical student, suggest that Keith see a doctor. Keith complies and makes an appointment with a doctor. The doctor’s report looks like this: Keith is pale and underweight, his urine and blood pH are low, and the ketones in the urine and blood are high. The Na+ concentration in the blood is low. Keith seems to have possible nerve problems. The doctor explains that Keith is pale due to anemic conditions brought on by the poor diet. With a poor protein diet, Keith’s erythrocytes may not be making adequate hemoglobin. Because his diet is very low in carbohydrates, his body is metabolizing fat, which is causing the weight loss. By products of fat metabolism are ketones, which are acidic. This accounts for the increase in ketones in the urine and the blood and a drop in the pH. A drop in blood pH will inhibit the small intestine from putting Na+ into the bloodstream. Sodium ions are necessary for proper nerve function. In short, Keith needs to begin eating well-balanced meals.

 

a. Why is corn considered to be an incomplete protein?

 

b. How are ketones formed?

 

c. How are sodium ions involved in the nervous system?

 

d. How does this scenario relate to fad diets?

7. Analyze the need of climbers of Mt. Everest to set up camps at various levels and stay in those camps for a predetermined amount of time before proceeding with their climb to the top of the mountain.