Diatoms have cell walls composed of silicon dioxide.
A. silicon dioxide.
Answer: Wind-blown sand grains striking any solid object in their path can abrade the surface. Rocks are smoothed down, and the wind sorts sand into uniform deposits. The grains end up as level sheets of sand or are piled high in billowing sand dunes.
Explanation:
When organisms die they release the nutrients back to the soil
Answer:
enable capillarity
Explanation:
It is well known that water tends to adhere to the walls of the vessel in which it is contained. This is due to the force of adhesion which is defined as the force of attraction between unlike molecules. Cohesion is defined as the force of attraction between like molecules. In the case of a plant, cohesion of water molecules in the xylem vessels prevents the water column from breaking. The forces of adhesion, surface tension and cohesion are the basis of capillarity,that is, the rise of liquids in capillary tubes.
The accumulation of several mutations in the main gene on the virus's surface may be able to give H7N9 the ability to spread like human flu viruses do, passing from person to person through coughing and sneezing.