A 75-year-old patient with pneumonia presents with fever, tachycardia, and confusion. His temperature is 39.5°C (103.1°F). The attending physician explains that fever speeds up metabolic reactions in the body, including immune responses and bacterial proliferation. Which of the following best explains why higher temperature increases reaction rates?

A medical student is learning about melanoma and the use of BRAF inhibitors in patients with BRAF V600E mutations. How does a mutation in BRAF affect the RAS-MAPK pathway?

A researcher is studying the effects of a new drug that inhibits the RAS-MAPK pathway for its potential in treating non-small cell lung cancer (NSCLC) with EGFR mutations. At which step in the RAS-MAPK pathway does the drug most likely intervene if it is targeting the MEK protein?

A 55-year-old woman presents with a newly diagnosed metastatic colorectal cancer. Her oncologist is considering targeted therapies based on the mutational status of her tumor. Genetic analysis reveals a mutation in the KRAS gene. Which of the following best describes how a KRAS mutation might affect the RAS-MAPK pathway?

A 62-year-old man with metastatic melanoma is started on vemurafenib, a BRAF inhibitor. His physician explains that his cancer is driven by a BRAF V600E mutation, and the drug works by blocking the MAPK signaling cascade at the level of BRAF, preventing tumor growth. Which of the following best describes the role of BRAF inhibitors like vemurafenib in targeting the RAS-MAPK pathway?

A 48-year-old woman presents with a newly diagnosed pancreatic adenocarcinoma. Molecular testing reveals a KRAS mutation, which is known to drive uncontrolled cell growth. The oncologist explains that this mutation results in constitutive activation of RAS, making the cancer more aggressive and difficult to treat with standard targeted therapies. Which of the following best explains how a KRAS mutation contributes to oncogenesis?

 A 55-year-old man presents with a non-small cell lung cancer (NSCLC) diagnosis. Genetic testing reveals a mutation in the KRAS gene, a component of the RAS-MAPK pathway. His oncologist explains that this mutation leads to uncontrolled cell proliferation due to continuous activation of the pathway, making his cancer resistant to certain targeted therapies. Which of the following correctly describes the initial step in RAS-MAPK pathway activation?

A 6-year-old boy presents with short stature, webbed neck, and a heart murmur. Echocardiography reveals pulmonary valve stenosis. Genetic testing reveals a mutation in the PTPN11 gene. His mother also has a history of short stature and similar facial features. Which signaling pathway is most likely affected in this patient?

 A 25-year-old male presents with symptoms of cystic fibrosis, a condition linked to a defect in the CFTR protein. Genetic testing confirms a mutation affecting protein folding. You recall that the rough endoplasmic reticulum plays a critical role in processing such proteins.  Which of the following processes is primarily associated with the rough endoplasmic reticulum in the context of CFTR protein production?

A 65-year-old man with a history of hypertension presents with shortness of breath and leg swelling. Echocardiography reveals reduced ejection fraction, and he is diagnosed with Congestive Heart Failure (CHF). His cardiologist notes impaired energy production in cardiac myocytes.  How does Congestive Heart Failure (CHF) alter the Gibbs free-energy change (ΔG) of ATP synthesis in cardiac cells?