Topic 2: Prokaryotes

Question 1

What domains contain prokaryotes?

Answer 1

Bacteria & archaea

Question 2

What are the components of prokaryotes?

Answer 2

plasma membrane
cytoplasm
ribosomes
NO membrane bound organelles

Question 3

How do prokaryotes undergo cellular respiration without a mitochondria?

Answer 3

they use fermentation or aerobic respiration through plasma membrane

Question 4

What is peptidoglycan?

Answer 4

a carbohydrate polymer in cell wall

this is a characteristic of BACTERIA only

Question 5

What does the gram stain process tell us?

Answer 5

what the cell wall in the bacterial cell contain

Question 6

What is the process of gram staining?

Answer 6

1. stain with crystal violet dye (purple) & iodine
2. rinse with alcohol
3. stain with safranin dye (pink)

Question 7

What does a gram positive bacteria look like?

Answer 7

stains purple
thick wall - primarily peptidoglycan
crystal violet retained & masks safranin

Question 8

What does a gram negative bacteria look like?

Answer 8

stains pink
thin peptidoglycan layer
crystal violet rinses out, safranin visible
contains lipopolysaccharide outer layer so harder to treat & more dangerous

Question 9

positive taxis move…

Answer 9

towards stimulus

Question 10

negative taxis move…

Answer 10

away from stimulus

Question 11

What are the 3 recombination mechanisms & what happens during each?

Answer 11

1. Transformation - prokaryotic cell takes up DNA from foreign environment
2. Transduction - phages transfer prokaryotic genes from one cell to another
3. Conjugation - direct transfer of genetic material from one cell to another

Question 12

What are the 4 major nutritional modes?
the 2 for autotrophs? 
the 2 for heterotrophs?
energy source 
carbon source

Answer 12

autotrophs

• photoautotrophs: light energy source; CO2 carbon source
• chemoautotrophs: inorganic chemicals; CO2 carbon source (unique to certain prokaryotes)

heterotrophs

• photoheterotrophs: light energy source; organic compounds (unique to certain aquatic & salt loving prokaryotes)
• chemoheterotrophs: organic compounds; organic compounds

Question 13

Where did mitochondria evolve from?

Answer 13

endosymbiosis of proteobacteria

Question 14

Where did chloroplasts evolve from?

Answer 14

endosymbiosis of cyanobacteria