End-of-Course Test Study Guide  Part 5 of 7   (15% of Final Average!!!!)

Content Domain 5: Viruses, Bacteria, Protists, and Fungi

Viruses

1.      Viruses are [living, nonliving]. They are composed of an outer protein coat, with nucleic acid inside. They must replicate inside of a host (where).

2.      When a virus injects its DNA into the host cell, it hijacks the host, forcing it to make copies of viral DNA. Once the viral proteins are assembled, the cell ruptures, releasing the viruses. This is referred to as the lytic cycle.

3.      If the viral DNA is not immediately copied, it becomes integrated within the host's DNA. When the host cell divides, the daughter cells produced will also contain copies of the provirus. The virus may be dormant for several years in this state, but it is being spread. This is called the lysogenic cycle. After time the lytic cycle will take over.

4.      Some common diseases caused by viruses are AIDS, chickenpox, hepatitis, herpes, influenza, measles, mumps, polio, rabies, smallpox.

5.      Viruses do not respond to antibiotics. The body produces interferons to help fight viruses. Animals can receive immunity from viruses through vaccines, which is when the animal is injected with dead or weakened viruses so that antibodies will be produced against it.

Bacteria

6.      Bacteria belong to the Kingdoms Archaebacteria & Eubacteria. They are single-celled organisms [with, without] a nucleus. Therefore they are referred to as prokaryotes.

7.      Most bacteria are heterotrophs because they must get food from an outside source. However, blue-green bacteria are autotrophs who do photosynthesis. Some perform chemosynthesis, getting food from chemical compounds.

8.      The three shapes of bacteria are coccus (which is round/spherical), bacillus (which is rod-shaped), and spirilla, (which is spiral-shaped).

9.      The circular DNA of bacteria is called a plasmid. Some bacteria also have a tail, called a flagellum. Some bacteria form endospores, in which the DNA is protected in a coating until conditions are favorable. The process whereby bacteria reproduce is referred to as binary fission. They cannot do mitosis, since there is no nucleus.

10.  In what ways are bacteria beneficial to us? decomposing dead organisms, nitrogen fixation in root nodules, live in intestines & help break down food/make vitamins, clean up oil spills

11.  What are some foods produced with bacteria? cheese, yogurt, sauerkraut, soy sauce, pickles, sourdough bread...

12.  Some common diseases caused by bacteria are cholera, diptheria, leprosy, Lyme disease, meningitis, plague, pneumonia, syphilis, tetanus, tuberculosis, typhoid fever

13.  Some bacteria cause disease by releasing toxins, while others cause disease by breaking down tissues for food. Bacterial diseases can be transmitted by air, in food or water, direct contact, or vectors (like ticks, fleas, lice, raccoons, etc.). To fight bacterial infections, antibiotics may be taken.

14.  Some ways to prevent bacterial infection are skin & surfaces should be washed, food should be cooked thoroughly, contaminated water should be boiled.

Protists

15.  Kingdom Protista is composed of mostly single-celled organisms that all have a membrane-bound nucleus. Thus, they are referred to as eukaryotes.

16.  Plant-like protists are known as algae; animal-like protists are referred to as protozoa, while fungus-like protists are just fungus-like protists!

17.  Protozoa are classified based on their method of locomotion.

18.  Algae contain chlorophyll and accessory pigments in order to do photosynthesis. They must live in a moist environment. They are generally classified based on the color pigments they contain.

19.  How are protists beneficial? food chain in aquatic ecosystems, oxygen source, used in soups and salads, used to thicken foods, like ice cream, pudding, and soups, used in medicines, used to make agar, used to make plastics and paints

20.  What are some diseases caused by protists? Malaria, African sleeping sickness, giardia

21.  What is an algal bloom? when algae reproduce rapidly. it causes a decrease in nutrients in the water, which results in death and decomposition, which depletes the oxygen in the water.

22.  What causes red tides? Massive blooms of dinoflagellates. They produce toxins that become concentrated in shellfish and can kill fish and make people sick.

Fungi

23.  Fungi are usually multi-celled organisms that must decompose to get energy. Unlike plants, they DO NOT perform photosynthesis.

24.  Fungi are made of filaments called hyphae, which intertwine into a tangled mass known as a mycelium. Their cell walls are composed of chitin.

25.  Fungi reproduce both sexually and asexually. They are classified based on the way they form spores.

26.  How are fungi beneficial? break down organic material, thereby recycling nutrients; make antibiotics

27.  What are some foods produced with fungi? bread, alcoholic beverages, some cheeses, edible fungi: morels, mushrooms, truffles

28.  What are some diseased caused by fungi? ringworm, athlete's foot, thrush, yeast infection in animals.  in plants: wheat rust, food mildew, corn smut...

29.  What are some negative effects of fungi? attack food, clothing, and paper