Preposition Test 1

[Mr. Kyaw Min Lwin]

For Dear Learners,

An immune system is a collection--- mechanisms within an organism that protects-- infection-- identifying and killing pathogens. It detects pathogens ranging--- viruses-- parasitic worms and distinguishes them--- the organism's normal cells and tissues. Detection is complicated as pathogens adapt and evolve new ways--- successfully infect the host organism. To meet this challenge, several mechanisms have evolved- that recognize and neutralize pathogens. Even simple unicellular organisms such as bacteria possess enzyme systems that protect--- viral infections. Other basic immune mechanisms evolved-- ancient eukaryotes and remain-- their modern descendants, such as plants, fish, reptiles, and insects. These mechanisms include antimicrobial peptides called defensins, pattern recognition receptors, and the complement system. More sophisticated mechanisms, however, developed relatively recently, with the evolution of vertebrates. The immune systems --- vertebrates such as humans consist--- many types of proteins, cells, organs, and tissues, which interact--- an elaborate and dynamic network. As part of this more complex immune response, the vertebrate system adapts--- time--- to recognize particular pathogens more efficiently. The adaptation process creates immunological memories and allows even more effective protection-- future encounters--- these pathogens. This process--- acquired immunity is the basis--- vaccination.

kind regards.

[Mr. Kyaw Min Lwin]

Here is the answer for you.

An immune system is a collection of mechanisms within an organism that protects against infection by identifying and killing pathogens. It detects pathogens ranging from viruses to parasitic worms and distinguishes them from the organism's normal cells and tissues. Detection is complicated as pathogens adapt and evolve new ways to successfully infect the host organism. To meet this challenge, several mechanisms have evolved that recognize and neutralize pathogens. Even simple unicellular organisms such as bacteria possess enzyme systems that protect against viral infections. Other basic immune mechanisms evolved in ancient eukaryotes and remain in their modern descendants, such as plants, fish, reptiles, and insects. These mechanisms include antimicrobial peptides called defensins, pattern recognition receptors, and the complement system. More sophisticated mechanisms, however, developed relatively recently, with the evolution of vertebrates. The immune systems of vertebrates such as humans consist of many types of proteins, cells, organs, and tissues, which interact in an elaborate and dynamic network. As part of this more complex immune response, the vertebrate system adapts over time to recognize particular pathogens more efficiently. The adaptation process creates immunological memories and allows even more effective protection during future encounters with these pathogens. This process of acquired immunity is the basis of vaccination.

kind regards.

If you could do this test 100% correctly, your knowledge about prepositions is competent, I believe.
I'm always give priority to prepositions since the always make my writing look really stupid.

[Mr. Kyaw Min Lwin]

Please read I always give....they always...
Sorry for my bad habit.

Thank you.