The passage describes how viruses interact with the human body and how immunity is developed.
Complete the passage by writing a suitable word or words in each of the spaces.
All viruses contain genetic material in the form of a _______________\text{\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_}_______________ acid, which can be DNA or _______________\text{\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_}_______________, surrounded by a protein coat.
A viral pathogen, such as the influenza virus, enters the body and replicates inside host cells. The body's defense relies on the _______________\text{\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_}_______________ system. Specialised white blood cells, specifically _______________\text{\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_}_______________, play a key role in this defense. They produce specific protein molecules called _______________\text{\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_}_______________ that bind to the virus and help destroy it.
We can protect populations against such viral diseases by injecting a harmless form of the pathogen. This procedure is known as _______________\text{\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_}_______________ and triggers the body to produce _______________\text{\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_}_______________ cells, which ensure a rapid response if the person is infected by the active virus in the future.
