All of the following are components of the gastrointestinal tract except the:

Correct Answer: A

Rationale: The correct answer is A: spleen. The spleen is not a component of the gastrointestinal tract; it is part of the lymphatic system. The pharynx, esophagus, and stomach are all part of the gastrointestinal tract responsible for digestion and absorption of food. The spleen's main functions include filtering blood, storing blood cells, and supporting the immune system, making it unrelated to the digestive process.

Correct Answer: C

Rationale: The correct answer is C. Prostatitis is inflammation of the prostate gland, leading to symptoms like painful urination, fever/chills, and weak urine flow. Painful urination is due to irritation of the urinary tract by the inflamed prostate. Fever/chills indicate an infection, common in prostatitis. Weak urine flow is due to obstruction caused by the inflamed prostate. Choice A is incorrect as muscle aches, sore throat, and swollen lymph nodes are not typical symptoms of prostatitis. Choice B is incorrect as painful joints and nausea are not characteristic symptoms. Choice D is almost identical to the correct answer but includes an extra symptom of painful joints, which is not associated with prostatitis.

Correct Answer: C

Rationale: The correct answer is C (60 years) because as individuals age, their immune system weakens, making them more susceptible to infectious diseases. Around the age of 60, people are more likely to succumb to infections, leading to a higher mortality rate. Choices A, B, and D are incorrect because they are younger ages, and the likelihood of infectious diseases causing a significant proportion of deaths increases with age.

Correct Answer: B

Rationale: The central dogma of molecular biology, which describes the flow of genetic information from DNA to RNA to proteins, was first proposed by Francis Crick. Crick, along with James Watson, discovered the structure of DNA in 1953, leading to the understanding of how genetic information is stored and transmitted. Ernst Ruska was a physicist who developed the electron microscope, not related to genetic information flow. Camillo Golgi was an Italian biologist known for the discovery of the Golgi apparatus, not central to the central dogma. Carl Bender is not a prominent figure in the field of molecular biology. In summary, Francis Crick is the correct answer as he played a pivotal role in introducing the central dogma of molecular biology.

Correct Answer: C

Rationale: Step-by-step rationale for why choice C (Adenoviridae) is correct: 1. Adenoviruses commonly cause respiratory illnesses such as the common cold and bronchitis. 2. They are highly contagious and easily spread through respiratory secretions. 3. Adenoviruses are a common cause of viral conjunctivitis as well. 4. Other choices are incorrect because herpesviruses (choice A) typically cause different types of infections, papovaviruses (choice B) are not common respiratory pathogens, and poxviruses (choice D) are not typically associated with respiratory illnesses.