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Biology 2nd Baccalaureate

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13.1. Infection concept

What is infection?

The infection when occurs microorganism pathogen enters and proliferates within an organism. This abnormal situation is called infectious disease.

If an infectious disease can be easily transmitted to another individual, it is called a contagious disease, but not all infectious diseases are contagious.

Living beings have defense mechanisms to protect themselves from the entry of pathogenic organisms. They are grouped into two types:

Questions that have come out in University entrance exams (Selectividad, EBAU, EvAU)

Murcia, July 2021, question 4.5

Since March 2020 there has been a major crisis at the international level due to the health alarm situation caused by the SARS-CoV-2 coronavirus, a microorganism with a high transmission capacity. The infection caused has resulted in many cases in serious pneumonia and other conditions, as well as restrictions on the mobility of citizens.

a) Explain the term microbial infection, and how the microorganisms that cause disease are called. (0.25 points)
b) Mention four different routes of transmission of infectious diseases, and give an example of each type. (0.25 points)
c) Indicate any infectious disease caused by bacteria, fungi and viruses, and how they are controlled. Reason for your answer. (0.5 points)

Madrid, July 2021, question B3

In relation to infectious diseases:

a) Briefly describe the routes by which infectious diseases can be transmitted (1 point).
b) Indicate the type of causative agent and the preferred route of transmission of the following infectious diseases: Covid-19, rabies, cholera, malaria (1 point)


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Biology and Geology teaching materials for Compulsory Secondary Education (ESO) and Baccalaureate students.