Chapter 24 Review

Question 1

Describe the cell type, cell number, and nutrition of all bacteria.

Answer 1

Archaebacteria: unicellular, prokaryotic, autotroph and heterotroph
Eubacteria: unicellular, prokaryotic, autotrophic and heterotrophic

Question 2

Outline some general differences between archaebacteria and eubacteria.

Answer 2

Some general differences are: archaebacteria can live in extreme environments and eubacteria can not, archaebacteria are older, eubacteria are more common and the majority of bacteria are eubacteria.

Question 3

Outline the physiological difference between archaebacteria and eubacteria.

Answer 3

Eubacteria have peptidoglycan in their cell membrane

Question 4

Name and descrive the habitat of 3 types of archaebacteria.

Answer 4

Methanogens: can only live in anaerobic conditions such as the bottom of a swamp or in sewage. Thye can also liv ein the intestional tracts of humans and other animsl
Extremehalophils: liv ein environments with high salt concentrations, such as the Great Salt Lake and the Dead Sea
Thermoacidophils: live in extremely acidic environments that have high temperatures, such as hot springs, near volcanic cents on land or near hydrothermal vents, cracks in the ocean floor miles below the surgace that leak scalding acidic water

Question 5

Name and describe the three main shapes of bacteria.

Answer 5

Bacilli (sausage)
Cocci (clusters of balls)
Spirilla (spiral shaped)

Question 6

Indicate the difference between the prefixes staphylo-, stepto-, and diplo-.

Answer 6

Staphylo (grape like clusters)
Stepto (chains)
Diplo (two)

Question 7

Describe the gram stain technique used to classify eubacteria.

Answer 7

The gram stain is used to determine whether Eubacteria is gram positive or gram negative. Gram positive bacteria retains the purple stain in its thick peptidoglycan layer, while gram negative bacteria turn pink when stained du to small peptidoglycan layer.

Question 8

Be familiar with the four main phyla of eubacteria, their distinguishing characteristics (positive and negative), and examples.

Answer 8

Cyanobacteria- gram negative; produced oxygen in early Earth which gave rise to the atmosphere, thrive on nitrates and phosphates which cause bacteria to bloom in bodies of water, when they die heterotrophic bacteria cause them to decompose and oxygen is depleted from the body of water; photosynthetic and aerobic
Spirochetes- gram negative; heterotrophic, anaerobic, and aerobic; causes STI syphilis
Gram positive- mostly gram positive; autotrophic and heterotrophic, anaerobic and aerobic; the bacteria used to make yogurt, found in your oral cavity and gut where they slow the growth of disease causing bacteria, some are found in the soil where they produce antibiotics.
Proteobacteria- gram negative; heterotrohic and autotrohphic, anaerobic and aerobic; E.coli lives in human guts and helps make Vitamin K, responsible for food poisoning caused by salmonella

Question 9

Know the general structure of a prokaryotic cell, including the following organelles- chromosome, cell membrane, cell wall, capsule, pilus, flagellum, plasmid, cytoplasm.

Answer 9

Chromosome- carries genetic info inherited by past generations
Cell membrane- regulates movement of materials into and out of the cell
Cell wall- protects the cell and gives it shape
Capsule- protects the cell and assists it in attatching to other surfaces
Pilus- assists the cell in attatching to other surgaces
Flagellum- moves the cell
plasmid- contains some genes obtained through genetic recombination
Cytoplasm- contains DNA, ribosomes, and organic compounds required to carry out life processes

Question 10

Recognize the function of an endospore and how it enhances survival in some bacteria.

Answer 10

An endospore is a dormant bacterial cell that is formed in abnormal conditions. the endospores can survive antibiotic treatment which is why they enhance the survival of some bacteria.

Question 11

List three ways that endospores can be destroyed.

Answer 11

autoclave (high heat and pressure)
gases
sporicide

Question 12

Be familiar with the terms saprophyte, photoautotroph, and thermophilic.

Answer 12

Saphrocyte- Bacteria that feed on dead and decaying material
Photoautotroph- Bacteria that use sunlight as an energy source
Thermophilic- Bacteria that grow best in temperatures between 40 degrees C and 100 degrees C

Question 13

Name and descrive the three groups that bacteria are placed in based on their response to oxygen.

Answer 13

Obligate anaerobes- They cannot survive in the presence of oxygen. Ex. the obligate anaerobe, Clostridium tetani causes tetanus
Facultative anaerobes- Can live with or without oxygen. Ex. Esherichia cole (common in the human digestive tract)
Obligate aerobes- Bacteria that cannot survive without oxygen. Ex. Mycobacterium tuberculosis lives in the lungs and causes tuberculosis

Question 14

Compare the binary fission with conjugation.

Answer 14

Binary Fission- Step 1: cell dupicates DNA + genes. Step 2: cell starts to split. Step 3: two identical cells are formed.
Conjugation: The process by which living bacteria bind together, and one bacterium transfers genetic information to the other
Step 1: Plasmid replicates in donor bacterium. Step 2: Plasmid is transferred into the new bacterial cell through the conjugation pilus.

Question 15

Explain the process of bacterial conjugation, including the structures of the cell involved.

Answer 15

The process by which living bacteria bind together, and one bacterium transfers genetic information to the other
Chromosomal DNA (squiggly line)
Plasmid (DNA thingy like a circle)
Pilus (connects the cells)

Question 16

Know the difference between a bacterial plasmid and chromosome.

Answer 16

Bacterial Plasmid: Contains some genes obtained through genetic recombination
Chromosome- Carries genetic information inherited from past generations

Question 17

Differentiate between and exotoxin and an endotoxin in terms of what bacteria makes it, structural composition and effect it has on the human body.

Answer 17

Exotoxin: Gram positive (living), Made of proteins, nausea, vomiting, diarrhea, skin lesions, tetanus
Endotoxin: Gram negative (dead), made of carbohydrates and lipids, fever, body aches, and weakness. Damages vessels of the circulatory system, E. coli

Question 18

Know how antibiotics interfere with various bacterial cellular functions.

Answer 18

Some ways that antibiotics interfere with various bacterial functions are by inhibiting cell wall synthesis, inhiviting proteins synthesis and inhibiting cell metabolism

Question 19

Compare a broad-spectrum antibiotic to one that ratgets specific bacteria.

Answer 19

A broad-spectrum antibiotic is abe to affect a wide variety of organisms. An antibiotic that targets a specific bacteria will only have an effect on that bacteria whereas a braod spectrum antibiotic will get rid of all bacteria, even the good bacteria.

Question 20

Explain how broad-spectrum antibiotics have contributed to an increase in antibiotic resistant bacteria.

Answer 20

Broad-spectrum antibiotics have contributed to an increase in resistant bacteria because they kill all bacteria, even the good bacteria, so only the resistant bacteria are left.

Question 21

Name bacterial diseases that affect the nerves, intestines, and skin.

Answer 21

Nerves: botulism
Intestines: cholera
Skin: lyme disease

Question 22

List some positive uses of bacteria.

Answer 22

digestion, breakmaking (sourdough), cheese, artificial snow, yogurt, vitamin K aids in blood clotting, occupying spaces that may cause disease causing bacteria, bacteria in the soil is good for decomposing, buttermilk.