How are parasites and viruses similar?
Both are contagious diseases.
Both infect host organisms.
Both reproduce using host cells.
Both break down food using oxygen.

Both infect host organisms

Explanation: A virus is a microscopic particle that can infect the cells of a biological organism. ... They are similar to obligate intracellular parasites as they lack the means for self-reproduction outside a host cell, but unlike parasites, viruses are generally not considered to be true living organisms.

the overall balanced equation

6co2 + 6h2o > c6h12o6 + 6o2

sunlight energy

where: co2 = carbon dioxide

h2o = water

light energy is required

c6h12o6 = glucose

o2 = oxygen

b - the respond is innate and varies over time.

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