Module #9 Test

Question 1

Taxonomy

Answer 1

The science dealing with the description, identification, naming, and classifying of organisms

Question 2

Binomial nomenclature

Answer 2

Naming an organism with its gene and species name

Question 3

Antibiotic

Answer 3

A chemical secreted by a living organism that kills or reduces the reproduction rate of other organisms

Question 4

Pathogen

Answer 4

An organism that causes disease

Question 5

Saprophyte

Answer 5

An organism that feeds on dead matter

Question 6

Endosphere

Answer 6

A thick internal wall, made of several hard layers, produced by the bacterium, that encloses its DNA and other essential parts

Question 7

Conjugation

Answer 7

A temporary union of two organisms for the purpose of DNA

Question 8

Transformation

Answer 8

The transfer of a DNA segment from a nonfunctional donor cell to that of a functional recipient cell

Question 9

Transduction

Answer 9

The process in which infection by a virus results in DNA being transferred from one bacterium to another

Question 10

Virus

Answer 10

A non-cellular infectious agent that has two characteristics: (1) it’s composed of genetic material inside a capsid or protein; (2) it must infect a living cell in order to reproduce

Question 11

Lytic cycle

Answer 11

A virus enters a cell, hijacks the host cell’s DNA replication system, makes copies of itself, and causes the cell to burst releasing more viruses

Question 12

Lysogenic cycle

Answer 12

A virus enters a cell, embeds its DNA into the DNA of the host cell and is replicated along with the host cell’s DNA

Question 13

Vaccine

Answer 13

A weakened or inactive version of a pathogen that stimulates the body’s production of antibodies which aid in destroying the pathogen

Question 14

What are the taxonomic classification groups used by scientists, in order?

Answer 14

Domains, Kingdoms, Phylum, Class, Order, Family, Genus, Species

Question 15

An organism is a multicellular consumer made of eukaryotic cells. To what domain and kingdom does it belong?

Answer 15

Domain: Eukarya (because it has eukaryotic cells)
Kingdom: Animalia (because it is multicellular and a consumer)

Question 16

An organism is a single-celled consumer made of prokaryotic cells and lives in boiling-hot water. To what domain does it belong?

Answer 16

Domain: Archie (because it is a prokaryotic and is a thermophile.

Question 17

How would you correctly written in binomial nomenclature?

Answer 17

exa: Home sapiens (all in italics with only the genus name capitalized)

Question 18

How are bacteria classified?

Answer 18

Bacteria are usually found in on of theses three body shapes: coccus (round or spherical shaped), bacillus (rod shaped), or spirillum (spiral shaped)

Question 19

What is the most popular means by which bacteria obtain food?

Answer 19

Most bacteria are heterotrophic decomposers

Question 20

What type of bacterium has a cell wall made of a thick layer of peptidoglycan, readily absorbs the purple-blue dye, and becomes stained blue-purple?

Answer 20

Gram-positive bacterium

Question 21

What is asexual reproduction in bacteria called? List the basic steps in asexual reproduction among bacteria.

Answer 21

Asexual reproduction in bacteria is called binary fission. At first, the DNA loop attaches to a point on the plasma membrane. After that, the DNA is copied, and the copy is attached to a point on the plasma membrane near the original. Then, the cell wall elongates, which separated the two loops of DNA. Once they are sufficiently separated, new cell wall and plasma membrane material grow, closing the two loops off from each other. Eventually, the cell wall and plasma membrane pinch down, forming two cells where there was only one before.

Question 22

A sample of food is dehydrated, which kills all of the bacteria. However, in a few days, bacteria-free water is added to the food in a bacteria-free environment. Nevertheless, bacteria are in the food. How did the bacteria get there?

Answer 22

The bacteria that are there were in the food as endospores. The bacteria that were in the food before it was dehydrated formed endospores to survive a little while without water. When water was added of the food, the conditions were once again favorable for bacteria, so the cells burst from the endospores

Question 23

What are the three ways genetic recombination can occur in bacteria?

Answer 23

Can combine with other bacteria through conjugation. They can pick up genes or segments of genes from the environment in transformation. Or they can acquire new genetic information from viruses that have infected other bacteria in transduction.

Question 24

Even though genetic recombination among bacteria does not result in offspring, it can significantly affect the growth of the population. Why?

Answer 24

Genetic recombination can pass a trait from one bacterium to another. If that trait allows the recipient to survive conditions that it otherwise wouldn’t, the population is affected, because the recipient continues to live and reproduce asexually.

Question 25

What conditions are ideal for most bacteria to grow and reproduce?

Answer 25

Moisture, moderate temperatures, nutrition, darkness, and the proper amount of oxygen

Question 26

What methods exist to reduce the chance of bacterial contamination of food?

Answer 26

Heat the food so that most bacteria die and then seal it away from fresh air; dehydrate the food; freeze the food; or refrigerate the food

Question 27

Describe two examples of bioremediation

Answer 27

(1) to treat sewage, (2) to remove oil from water in oil spills, (3) to cleanup mining sites, (4) to remove pesticides and other chemicals from the land or water

Question 28

If a virus used DNA as its genetic material, is it alive? Why or why not?

Answer 28

No virus is alive, because a virus cannot reproduce on its own

Question 29

What is the general structure of viruses?

Answer 29

Most viruses are composed of a nucleic acid (either RNA or DNA) and a protein cost called a capsid.

Question 30

What is the most effective way to reduce the spread of bacterial and viral infections?

Answer 30

Good hygiene is the best way

Question 31

What is the following statement incorrect? “All bacteria cause disease.”

Answer 31

Because there are many bacteria that are helpful to humans and important in recycling chemicals like carbon and nitrogen

Question 32

What is the purpose of a vaccine?

Answer 32

To trick the immune system into making antibodies for a particular virus. Then when a person is exposed to the virus the memory cells will start making the antibodies again to fight off the viral infection.