Answer:
Cellulose is the main substance found in plant cell walls and helps the plant to remain stiff and strong. Humans cannot digest cellulose, but it is important in the diet as a source of fibre.
Explanation:
Answer:
The answer is D a retrovirus inserts DNA into the host cells genes
The outer coverings that are tough but, flexible provided protection to the land plants.
Answer:
Sound waves behave in predictable ways.
Sound waves are compression waves that transfer energy in molecules.
All sound requires a medium through which to travel.
Explanation:
I am pretty sure these are the right answers.
Answer:
Gap junctions
Explanation:
Gap junctions form pores that connect adjacent cells. In this way signaling molecules, ions and other substances can pass through the pore to the adjacent cell. This type of cell junctions are important in cardiac muscle responses, in brain signaling, during childbirth, etc.
