The correct answer is c. Genetic Variation. Bacteria are very numerous, ad random mutation of bacterial DNA generates a wide variety of change, including resistance.
Answer:
Moist walls - gases dissolve in the moisture helping them to pass across the gas exchange surface. Permeable walls - allow gases to pass through. Extensive blood supply - ensuring oxygen rich blood is taken away from the lungs and carbon dioxide rich blood is taken to the lungs.
Answer:
Xylem is one of the two types of transport tissue in vascular plants, phloem being the other. The basic function of xylem is to transport water from roots to stems and leaves, but it also transports nutrients.
Explanation:
The answer is C build muscle hair and nails
Explanation:
this is mainly because when water evaporates, it leaves behind minerals, and even pollutants and goes up as clean water
