Question 1

Which of the following does not consist of complete cells?&#10;A)viruses&#10;B)bacteria&#10;C)algae

Accepted Answer

Viruses are not considered complete cells because they cannot carry out their life processes without a host cell. They do not have the necessary machinery (such as ribosomes) to replicate their genetic material or carry out metabolic functions on their own. Bacteria and algae, on the other hand, are complete cells that can carry out their life processes independently.

Question 2

How could you show experimentally that a newly discovered disease-causing agent is a virus or a bacterium?&#10;A)test to see if is killed by high temperatures&#10;B)test to see if is killed by changes in pH&#10;C)test to see if it is metabolically active outside a living cell

Accepted Answer

Viruses are not metabolically active outside of a host cell, unlike bacteria, which can exhibit metabolic activity independently. Testing for metabolic activity outside a living cell can help differentiate between a virus (which would not show such activity) and a bacterium (which would).

Question 3

Why are bacteria in the human intestines beneficial?&#10;A)They eliminate mutations&#10;B)They speed evolution&#10;C)They prevent disease-causing bacteria from growing

Accepted Answer

Bacteria in the human intestines play a crucial role in preventing the growth of disease-causing bacteria. They help in digesting food and promoting a healthy immune system.

Deck 17: The Immune System and Disease