A virus<span> is a small </span>infectious agent<span> that </span>replicates<span> only inside the living </span>cells<span> of other </span>organisms<span>. Viruses can infect all types of </span>life forms<span>, from </span>animals<span> and </span>plants<span> to </span>microorganisms<span>, including </span>bacteria<span> and </span><span>archaea
</span>While not inside an infected cell or in the process of infecting a cell, viruses exist in the form of independent particles. These viral particles<span>, also known as </span>virions<span>, consist of two or three parts: (i) the </span>genetic material<span> made from either </span>DNA<span> or </span>RNA<span>, long </span>molecules<span> that carry genetic information; (ii) a </span>protein<span> coat, called the </span>capsid<span>, which surrounds and protects the genetic material; and in some cases (iii) an </span>envelope<span> of </span>lipids<span> that surrounds the protein coat when they are outside a cell. The shapes of these virus particles range from simple </span>helical<span> and </span>icosahedral<span> forms for some virus species to more complex structures for others. Most virus species have virions that are too small to be seen with an </span>optical microscope<span>. The average virion is about one one-hundredth the size of the average </span>bacterium<span>.</span>
Answer:
<u>A. a flea feeding on a dog </u>
Explanation:
A flea feeding on a dog is parasitic in nature considering a parasitic relationship, also known as parasitism, is between two organisms in which the parasite, lives on or in the other organism, the host, causing it some harm. The flea is the parasite and the dog is the host with the flea feeding on it causing harm.
Answer:
Blood leaves the heart through the pulmonic valve, into the pulmonary artery and to the lungs. Blood leaves the heart through the aortic valve, into the aorta and to the body. This pattern is repeated, causing blood to flow continuously to the heart, lungs and body.
Explanation:
Place a teaspoon of salt in a bottle cap or small cup and dampen it with a few drops of water (without dissolving it). Carefully place the wet salt and the hygrometer inside a see-through container and close tightly. You can use a zip lock bag provided it seals well and you leave some air inside as well
