BIO 101 MA#4

What is an emerging virus?

A virus that has just come to the attention of scientists

Nitrogen-fixing bacteria convert atmospheric nitrogen (N2 gas) into ammonium (NH4). Why is this conversion important for life on Earth?

Ammonium is a very important plant nutrient.

Which of the following do not get infected by viruses?

Animals, plants and bacteria can all be infected by viruses.

Halophiles are a type of ________.

Archaea

Which organisms contain the smallest, least complex cell types?

Bacteria

The practice of using bacteria to remove pollutants from the environment is called ________.

Bioremediaton

Patients with advanced AIDS often die from infections that do little harm to healthy people. Why?

HIV infects and destroys the helper T cells of the immune system.

The domain Eukarya is divided into kingdoms. Which of these kingdoms includes members that are highly diverse and do not fit neatly into a single classification scheme?

Protists

Which of the following statement is correct regarding the phylogenetic tree above?

The polar bear and the brown bear are the most recently evolved species.

If you look at unknown cells under a microscope, what could lead you to correctly conclude that they are prokaryotic cells?

They lack a nucleus.

The main hypothesis about the origin of the first living organisms is called ________.

biogenesis