Which of the following body sites commonly serve as portals of entry for microbes?

• A. Respiratory tract
• B. Pancreas
• C. Skin
• D. Liver

Answer: (C)

Verified step by step guidance

1. Understand the concept of 'portals of entry' in microbiology: these are the routes through which microbes enter the body to cause infection.
2. Recall the common body sites that serve as portals of entry, such as the respiratory tract, gastrointestinal tract, skin, and mucous membranes.
3. Evaluate each option given: the respiratory tract is a common portal of entry because microbes can be inhaled; the skin can serve as a portal if there are cuts or abrasions; the pancreas and liver are internal organs and not typical entry points for microbes.
4. Conclude that the respiratory tract and skin are correct answers because they are exposed to the external environment and can allow microbial entry, whereas the pancreas and liver are not common portals of entry.
5. Summarize that portals of entry are typically external or exposed surfaces, and internal organs like the pancreas and liver are not considered common entry points for microbes.