The correct option is D.
A virus refers to an infectious micro organism that is made up of nucleic acid molecule that is enclosed within a protein coat. Viruses are only able to reproduce and multiply when they come in contact with living cells, in the absence of living cells they remain dormant and they do not show any sign of been a living thing. The nuclei acid molecule of a virus can be in form of a DNA molecule or a RNA molecule.
Answer:
Cell surface receptors (membrane receptors, transmembrane receptors) are receptors that are embedded in the plasma membrane of cells. They act in cell signaling by receiving (binding to) extracellular molecules. They are specialized integral membrane proteins that allow communication between the cell and the extracellular space.
Explanation:
D. Asteroids vary greatly in size and are mostly made up stone, iron and nickel
Answer:
Are there any choices to choose from?
Explanation:
Answer:
I think that it is closest to the sun.
Explanation:
it is the second closest planet to the sun.