lesson 9 - bacteria and archaea

Question 1

what are the three domains of life?

Answer 1

bacteria, archaea, and eukarya

Question 2

which domains of life are prokaryotic?

Answer 2

bacteria and archaea

Question 3

do prokaryotes have a nucleus? (membrane bound organelles)

Answer 3

no

Question 4

what membranes do prokaryotes have?

Answer 4

plasma membrane - respiratory membrane and thylakoid membrane

Question 5

can oxygen build up if it reacts with iron?

Answer 5

no

Question 6

what are stromatolites?

Answer 6

rocks formed by sedimentary layers on bacterial mats

Question 7

what is the main source of atmospheric oxygen?

Answer 7

oxygenic photosynthesis by cyanobacteria

Question 8

which bacteria created oxygen thru photosynthesis?

Answer 8

cyanobacteria

Question 9

what are extremophiles?

Answer 9

organisms that live in extreme conditions

Question 10

what are extreme halophiles?

Answer 10

biological organisms that thrive in highly saline environments

Question 11

what are extreme thermophiles?

Answer 11

organisms that thrive in very hot environments

Question 12

what are the three basic prokaryotic shapes?

Answer 12

coccus (round), bacillus (rod), spiral (twisty)

Question 13

what is a heterocyst?

Answer 13

special bacterial cell that helps capture nitrogen from the air and turn it into nutrients for other bacteria

Question 14

true or false - bacteria break down waste and help plants grow

Answer 14

true

Question 15

capsule is an important part in bacteria, what does it do?

Answer 15

protective layer outside the cell wall

Question 16

what is the capsule made of?

Answer 16

polysaccharides or proteins

Question 17

how does capsule play a role in the attachment to surfaces?

Answer 17

helps bacteria stick to surfaces to form colonies

Question 18

how does the capsule help bacteria survive?

Answer 18

capsule makes it hard for white blood cells to attack the bacteria, helping it avoid being destroyed

Question 19

how do fimbriae and pili help bacteria

Answer 19

they help bacteria stick to surfaces

Question 20

which domain do eukaryotes share a common ancestor with?

Answer 20

archaeans

Question 21

gram-positive

Answer 21

thick peptidoglycan

Question 22

what colour stain in gram positive bacteria?

Answer 22

purple stain

Question 23

gram negative

Answer 23

thin peptidoglycan

Question 24

what colour stain is gram negative bacteria?

Answer 24

red stain

Question 25

why are gram negative bacteria more resistant to antibiotics?

Answer 25

they have an extra outer membrane with lipopolysaccharides, which provides additional protection

Question 26

why are some gram-negative bacteria harmful?

Answer 26

their lipopolysaccharides can be toxic

Question 27

what is the structure of prokaryotic DNA?

Answer 27

small, circular chromosome with no nucleus

Question 28

what are plasmids?

Answer 28

small, extra pieces of DNA that bacteria can share with each other

Question 29

what are the three factors contributing to prokaryotic genetic diversity?

Answer 29

rapid reproduction, mutation, and genetic recombination

Question 30

rapid production

Answer 30

bacteria divide quickly

Question 31

mutation

Answer 31

changes in DNA happen more often, leading to new traits

Question 32

genetic recombination

Answer 32

bacteria can transfer genes, sharing plasmids and gaining new traits

Question 33

what is binary fission?

Answer 33

rapid asexual reproduction method where bacterial cell divides into two identical daughter cells

Question 34

what are the three methods of genetic recombination in bacteria?

Answer 34

transformation, transduction, and conjuction

Question 35

transformation

Answer 35

bacteria take in free DNA from their envrionment

Question 36

transduction

Answer 36

viruses can transfer DNA from one bacteria to another

Question 37

conjugation

Answer 37

bacteria directly swap DNA with each other