Virus and Bacteria

What is a virus envelope?

- A phospholipid bilayer membrane surrounding the nucleocapsid

What is the sticky capsule used for in a bacteria cell?

For attachment to host or other bacteria

Viruses are host ______?

Specific

how can you prevent bacterial infections?

hand washing, antibacterial, substances, cleaning , cooking food thoroughly

How do bacteria reproduce asexually?

through binary fission chromosome replicates & then cell divides. It is rapid and all new cells are identical (clones)

Why do bacteria form endospores?

to help them survive in the harshest conditions. (little food)

what is another name for eubacteria?

true bacteria

What is a bacteriophage?

virus that attacks bacteria

What is virulence?

ability to cause disease

What is reverse transcriptase?

causes synthesis of complementary DNA molecule (cDNA) using virus RNA as a template

What is a pathogen?

disease causing organism

what type of prokaryote are most bacteria a part of?

domain eukarya

What are the 5 main shapes of bacteria? Know the scientific name and common name.

>bacillus: rod shaped >coccus: spherical (round) >vibrio: comma shaped with flagella >spirillum: spiral shape >spirochete: wormlike spiral shape

Archea live in what environment?

>can live in extremely harsh environment >they do not require oxygen and can live in extremely salty environments as well as extremely hot environment

what are key traits for retroviruses?

>contain RNA, not dna >Family Retroviriade >Contain enzyme called Reverse Transcriptase >When it infects a cell, it injects its RNA and reverse transcriptase enzyme into the cytoplasm of that cell

how do bacteria cause infection (2 ways)?

>invade and attack cells (ex: tuberculosis) >make poisons or toxins that travel through the blood stream (ex: botulism)

What are the different types of flagella?

>monotrichous: 1 flagella >lophotrichous: tuft at one end >amphtrichous: tuft at both end >peritrichous: all around bacteria

what are different methods of respiration in eubacteria? what do they each mean?

>obligate aerobes- requires O2 (tuberculiosis bacteria) >obligate anaerobes- die if O2 is present (tetanus) >facultative anaerobes- don't need O2, but aren't killed by it (E.coli)

What are the two structures that every virus has? What other structures can viruses have?

All viruses contain the following two components: 1) a nucleic acid genome and 2) a protein capsid that covers the genome. Together this is called the nucleocapsid. In addition, many animal viruses contain a 3) lipid envelope.

Characteristics of each sub group of 3/3

Extreme Halophiles: live in very salty water, use salt to generate ATP (energy), Dead Sea, great day salt lake inhabitants

What are the different nutrition methods of eubacteria? What do they each mean?

Saprobes- feed on dead organic matter Parasites- feed on a host cell Photoautotroph- use sunlight to make food Chemoautotroph-oxidize inorganic matter such as iron or sulfur to make food

What is viral latency?

The ability to become dormit inside the cell . They remain inactive for long periods of time (years). They later activate to produce new viruses in response to same external signal.

when do some bacteria become pathogenic?

when they come in contact with tissues they DO NOT normally inhabit

What is a virus?

a non-cellular particle made up of genetic material and protein that can invade living cells

what does the family end in?

-viridae

what does the genus end in?

-virus

What are the 3 sub groups of archea?

> methangogens > thermoacidophiles > extreme halophiles

5 steps of lytic cycle

>Attachment >Entry: The bacteriophage injects its nucleic acid into the bacterial cell >Replication: The host's metabolic machinery makes viral nucleic acid & proteins >Assembly: New virus particles are assembled >Release: The host cell breaks open and releases new virus particles

Describe the basic cell structure of a bacterium?

>Have small rings of DNA called plasmids >Unicellular >Small in size (0.5 to 2um)

what are viruses identified by?

>RNA or DNA virus >do or don't have an envelope >capsid shape >HOST they infect

What is flagella? What is it made of? What is used for?

A bacteria that are motile have appendages. Made of flagellin. Used for classification.

What is a prophage (provirus)?

A bacterial virus that has integrated into its host cell genome

What is a vaccine?

An attenuated virus is weakened, virgorous virus. "Attenuated" meaning to procedures that weaken an agent of disease (heating). A vaccine against a viral disease can be made from an attenuated, less virulent strain of the virus

what are two main types of prokaryote?

Archaea & Bacteria

what are numerous organisms on earth? how far back do they date?

Bacteria. Earliest fossils date 2.5 billion years old.

How do bacteria reproduce sexually?

By conjugation. They form a tube between 2 bacteria to exchange genetic material, which is held together by pili. *new cells NOT identical*

how do you label a viral species?

Class I viruses contain a single molecule of double-stranded DNA (dsDNA). In the case of the most common type of class I animal virus, viral DNA enters the cell nucleus, where cellular enzymes transcribe the DNA and process the resulting RNA into viral mRNA.

What is Beijerinck known for?

Coined the Latin name "virus" meaning poison. He studied filter plant juices & found the caused healthy plants to become sick.

What are the 3 grouping of bacteria?

Diplo- groups of two Strepto- chains Staphylo- grapelike clusters

After studying sick tobacco plants, what did Wendell Stanley discover?

Discovered viruses were made of nucleic acid and protein.

what viruses are good examples of latent viruses?

HIV & Herpes

how can bacteria be helpful?

HUMANS: break down food in the digestive system, produce vitamins (like vitamin B), & prevent vitamins bacteria from causing infection FOOD: used to ferment (chemical break down) certain foods; dairy, pickles, soy, sauce, vinegar, etc. ECOSYSTEM: some produce oxygen (like cyanobacteria), some fix nitrogen (N2->NH3) to be used by plants and animals, used for bioremediation to break down pollutants (i.e. oil), clean up oil spills and industrial accidents

What are the possible shapes of a virus unit?

Have variety in shapes. May be Helical shapes like Ebola virus or Polyhedral shape like the influenza virus. Others have more complex shapes like bacteriophages.

What was Edward Jenner known for?

He developed the smallpox vaccine in 1796 using milder cowpox viruses.

what are two cycles a virus can go through?

Lytic & Lysogenic cycle

What is the viral capsid composed of?

Made of individual protein subunits

Characteristics of each sub group of 1/3

Methanogens: live in anaerobic environments (no oxygen), get energy be changing H2 & CO2 into methane gas, found in swamps, sewage treatment plants, digestive tracts of animals, break down cellulose in cows stomach, and produce marsh (methane) gas

What is the subunit of the capsid called?

Protomers

what are the most common bacteriophage?

The most commonly studied T-phages are T4 and T7.

Characteristics of each sub group of 2/3

Thermoacidophiles: live in extremely not environments, found in volcanic vents, hot springs, cracks on ocean floor that leak acid

what does bacteriophage attack?

They infect E. coli an intestinal bacteria.

What do viral spikes do?

To help attach to the host cell

Why do viruses need a host cell?

Viruses reprogram the cell to make new viruses

how do you designate a subspecies?

a category in biological classification that ranks immediately below a species and designates a population of a particular geographic region genetically distinguishable from other such populations of the same species and capable of interbreeding successfully with them where its range overlaps theirs.

what are ways to develop antibiotics resistance?

overuse- using antibiotics when bacteria aren't causing illness underuse- when you don't take the full course of antibiotics misuse- using antibiotics for things other than what they are specified for

What is the cell wall of a bacterium made of?

peptidoglycan

what is name of the DNA ring in bacteria?

plasmids

What are pili? What are they used for?

short protein appendages. Used in conjunction for exchange of genetic information.

how do antibiotics work?

that can slow or stop the growth of bacteria, it prevents the cell wall from developing.