Prokaryotes

Question 1

what is the internal organization of prokaryotes?

Answer 1

• small and simpler than eukaryotes
• Plasma Membran
• Ribosomes
• Cytoplasm
• circular Chromosome (in nucleoid region)

Question 2

what is the job of the cell wall in prokaryotes?

Answer 2

• protect cell
• maintain shape
• prevent bursting

Question 3

peptidoglycan

Answer 3

• carbohydrate polymer in cell wall

- characteristic of Domain Bacteria only

Question 4

gram stain process

Answer 4

reveal type of cell wall in bacterial sample

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

Question 5

does Penicillin interfere with peptidoglycan synthesis or lipopolysaccaride

Answer 5

peptidoglycan (gram +)

Question 6

what is the outer layer of gram - bacteria?

Answer 6

lipopolysaccaride

Question 7

is gram + or - resistant to antibiotics?

Answer 7

negative (-)

Question 8

is flagella an example of homologous or analogous structures?

Answer 8

analogous. similar functions, but arose independently. convergent evolution

Question 9

binary fission

Answer 9

• 1 cell divides into 2 asexual

- very rapid in optimal conditions

Question 10

do prokaryotes reproduce asexually or sexually?

Answer 10

asexually

Question 11

mutations in prokaryotes

Answer 11

• short generations and large population (high genetic variation/ diversity = many alleles/gene)
• when alleles increase survival and reproduction (population changes)

Question 12

what’s a negative consequence (for us) of rapid evolution in bacteria?

Answer 12

antibiotics become less and less effective, allows bacteria to become quickly resistant

Question 13

how do sexual eukaryotes recombine and what happens as a result?

Answer 13

meiosis + fertilization

new allele combinations

Question 14

what are the three recombination mechanisms and are they examples of horizontal or vertical gene transfer?

Answer 14

transformation, transduction, and conjugation

horizontal

Question 15

transformation

Answer 15

prokaryotic cell take up foreign DNA from environment (Griffith’s experiment)

Question 16

transduction

Answer 16

phages transfer prokaryotic genes from one cell to another

Question 17

conjugation

Answer 17

direct transfer of genetic material from one cell to another, usually of same species

• involves F (fertility) factor - often a plasmid
• required for production of pilus: appendage for DNA transfer
• F+ cell

Question 18

what are the two alternatives to prokaryotic metabolism?

Answer 18

• fermentation : make ATP without ETC

- anaerobic respiration : ATP with ETC using a different e- acceptor

Question 19

facultative anaerobes

Answer 19

use o2 when present, fermentation or anaerobic respiration when absent

Question 20

what drives prokaryotic systematic?

Answer 20

rRNA sequences

Question 21

what are the two prokaryotic domains?

Answer 21

bacteria and archaea

Question 22

is archaea more closely related to Bacteria or Eukarya?

Answer 22

Eukarya

Question 23

proteobacteria

Answer 23

• large diverse, 5 groups

- endosymbiosis of alpha proteobacteria - > mtiochondria

Question 24

cyanobacteria

Answer 24

• photoautotrophs - oxygenic photosynthesis

- endosymbiosis of cyanobacteria - > chloroplasts

Question 25

extremophiles

Answer 25

- Archaea - organisms that thrive in extreme conditions - halophiles: high salt environments - thermophiles/hypothermophiles: hot environments - methanogens: release methane as byproduct of metabolism (obligate anaerobes and often in marshes and swamps)