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.
A spiral galaxy is a galaxy where the stars and gas clouds are concentrated mainly in one or more spiral arms. Most spiral galaxies consist of a flat, rotating disk containing stars, gas and dust, and a concentration of stars known as "the bulge". The disk of stars orbiting the bulge separates into arms that circle the galaxy. These spiral arms contain gas and dust and younger stars that shine brightly before they dull. Most of the galaxies that scientists have discovered so far are spiral galaxies. One example of a galaxy in our solar system is The Milky Way. Spiral galaxies make up roughly 72 percent of the galaxies that scientists have observed. How the spiral arms form continues to puzzle scientists. One theory suggests the galaxy arms could be the result of density waves traveling through the outer disk. Galaxies at a whole are quite a fascination.
Answer:
C
Cells have different shapes because they do different things. ... The shapes of cells have evolved to help them carry out their specific function in the body, so looking at a cell's shape can give clues about what it does. Neurons are cells in the brain and nervous system.
