Viruses can only replicate with in a cell or living tissue applies to a viral infection.
Viral infections are infections that are caused by viruses. Viruses are microscopic organisms that contains a core of genetic material (DNA or RNA) enclosed by a protein coat. Viruses are not made of cells and they are very tiny and smaller than bacteria. Viruses require a living cell (host organism) to replicate and produce other viruses similar to them. Viral infections cannot be treated with antibiotics, antiviral medicines are used instead. Examples of viral infections include; common cold, flu, smallpox, HIV/AIDS and Ebola.
They let things in and out
Answer:
B.They survive and thrive in inhospitable places.
Explanation:
"Extremophile, an organism that is tolerant to environmental extremes"
Answer: Contractile vacuole of amoeba will shrink/contract when the organism is placed in sea water.
Contractile vacuole is a subcellular structure ( mainly found in protists) that is involved in the regulation of water quantity inside a cell.
As we know that water always flow from a hypotonic ( where solute concentration is less) to a hypertonic ( where solute concentration is more) solution. Sea water is a hypertonic solution as the concentration of salt is very high. Therefore, in this case, water will flow from contractile vacuole to outside of the organism.
Thus, contractile vacuole of amoeba will contract as it will lose water when placed in sea water.