15: evolutionary relatedness

Question 1

what is endosymbiosis?

Answer 1

one organism lives inside the other and both benefit

Question 2

What is an example of an endosymbiotic relationship? What does each gain?

Answer 2

our relationship w the good bac flora in our colon; we get vitamin K and they crowd out potential pathogens; the get food and shelter

Question 3

What is an example of bacteria in our colon?

Answer 3

E. coli

Question 4

What happens when the normal flora of the colon is wiped out by antibiotics? What is the name of the pathogen?

Answer 4

the person can develop a colon infection w Clostridium difficle

Question 5

What are some characteristics of Clostridium difficle?

Answer 5

they form spores; difficult to get rid of bc it is not affected by antibiotics

Question 6

What happens after the C. difficle spores germinate?

Answer 6

it causes pseudomembranous colitis (inflammation of colon)

Question 7

What is used to treat C. difficle? what is it? how can it be administered?

Answer 7

fecal transplant; feces from another person in moved into the colon; colonoscopy, enema, or capsule

Question 8

What does the endosymbiotic theory state?

Answer 8

the mitochondrion developed when a large nucleated cell engulfed an aerobic bacteria

Question 9

what is a heterotroph?

Answer 9

org that gets its food from complex organic molecules

Question 10

what is a phototroph?

Answer 10

org that uses light to create its energy source

Question 11

what is the evidence for the endosymbiotic theory?

Answer 11

basically the bac and mitochondria ribosomes are very similar:
1. both have circular chromosomes
2. both have ribosomes smaller than the euk ones
3. ribosomes in both are resistant to diphtheria toxin and sensitive to streptomycin

Question 12

What does diphtheria toxin do? How? which ribosomes does it affect?

Answer 12

stops elongation of the peptide during translation by interfering w elongation factor; cytoplasmic (euk)

Question 13

what does streptomycin cause in cytoplasmic ribosomes?

Answer 13

no effect

Question 14

What does streptomycin do? in which org?

Answer 14

interferes with initiation of translation= by preventing the binding to the ribosome of the tRNA carrying the 1st amino acid (N-formylmethionine).

Question 15

What is the first amino acid in bacteria? and Eukarya and Archaea?

Answer 15

N-formylmethionine; methionine

Question 16

what is a phylogenetic tree?

Answer 16

diagrams used to show genetic and evolutionary relationships bw organisms

Question 17

What is the evidence for eukarya branching from archaea?

Answer 17

1. similarity of promoters
2. number of subunits in RNA Pol
3. sensitivity of ribosomes to diphtheria toxin
4. 1st amino acid in a protein

Question 18

what is a promoter?

Answer 18

control region of a gene

Question 19

In what process is RNA Pol involved?

Answer 19

transcription

Question 20

what is a subunit?

Answer 20

polypeptide

Question 21

What is a plasmid? what can it carry?

Answer 21

mini chromosome that can be passed around from one bac to another; antibiotic resistance genes

Question 22

the ______________________ describes how chloroplasts and ____________ evolved. Protozoa are considered _________ bc they use organic molecules for energy. __________ causes infections in some people who have taken antibiotics. It causes a disease called _________________________.

Answer 22

endosymbiotic theory; mitochondira; heterotropes; C. difficle; pseudomembranous colitis

Question 23

what is proteobacteria?

Answer 23

the phylum gram neg bacteria belong to

Question 24

What kingdom does bacteria belong to?

Answer 24

Monera

Question 25

the SSU rRNA has stems and loops giving it a ________________ where it folds like proteins

Answer 25

secondary structure

Question 26

stems are areas where

Answer 26

the rRNA base pairs w itself

Question 27

loops are areas where

Answer 27

there is no base pairing within the rRNA molecule