Prokaryotes

Question 1

key difference between bacteria and archea

Answer 1

bacteria have cell walls made of peptidoglycan

Question 2

s layer

Answer 2

An S-layer is a part of the cell envelope found in almost all archaea, as well as in many types of bacteria. It consists of a monomolecular layer composed of identical proteins or glycoproteins. This structure is built via self-assembly and encloses the whole cell surface.

Question 3

anitbiotic function

Answer 3

antibiotics break the sugar bonds in the peptidoglycan wall

Question 4

extremophiles

Answer 4

organisms that have been discovered that survive in conditions that were previously thought unable to sustain life

Question 5

similarities to bacteria

Answer 5

both have a circular chromsome with compact dna
no nuclear membrane
no cell organelles
they have similar cell morphology

Question 6

cell wall composition

Answer 6

cell wall composition varies
proteins, glycoproteins, polysaccharides or all of them.
some have no cell walls
a common feature is that none of them contain peptidoglycan.

Question 7

common ancestors

Answer 7

archea and eukaryotes share a common ancestor, even though they look completely different
bacteria and bacteria are not closely related even though they look similar

Question 8

pseudomurein

Answer 8

Pseudopeptidoglycan (also known as pseudomurein) is a major cell wall component of some Archaea that differs from bacterial peptidoglycan in chemical structure, but resembles bacterial peptidoglycan in function and physical structure.

it is structurally similar to peptidoglycan

a unique amino sugar forms the backbone. the linkages are not sensitive to lysozyme or penicillin.

Question 9

cell membranes

Answer 9

they have unique cell membranes.
the lipid tail is not a fatty acid - they vary in structure.
an ether linkage bonds the fatty acids to glycerol.

the lipids can form bi or mono layers.

Question 10

hypoxic conditions

Answer 10

Hypoxia is a condition in which the body or a region of the body is deprived of adequate oxygen supply at the tissue level.

Question 11

hami

Answer 11

a long pilli-like structure that works as a grappling hook.

they use this structure as a grappling hook to attach to surfaces or to each other.

Question 12

archaella

Answer 12

unique flagella

for motility

Question 13

what is the fastest organism on earth

Answer 13

a flagellated archael cell

Question 14

LUCA

Answer 14

the last common ancestor

Question 15

controversy of classification

Answer 15

linnean taxonomy and phylogeny can differ

phylogenetically related organisms may not share morphology/phenotype

Question 16

discover that archea and bacteria were different

Answer 16

The scientific community was understandably shocked in the late 1970s by the discovery of an entirely new group of organisms – the Archaea. Dr. Carl Woese and his colleagues at the University of Illinois were studying relationships among the prokaryotes using DNA sequences, and found that there were two distinctly different groups. Those “bacteria” that lived at high temperatures or produced methane clustered together as a group well away from the usual bacteria and the eukaryotes. Because of this vast difference in genetic makeup, Woese proposed that life be divided into three domains: Eukaryota, Eubacteria, and Archaebacteria. He later decided that the term Archaebacteria was a misnomer, and shortened it to Archaea. The three domains are shown in the illustration above at right, which illustrates also that each group is very different from the others.

Question 17

differences in dna as a function

Answer 17

differences in dna is a function of the number of mutations accumulated since the last common ancestor.

Question 18

why arent archea sensitive to lysozyme

Answer 18

lysozyme is an enzyme that targets the backbone of the peptidoglycan in bacterial cell walls
in archea, the linkages that form the backbone are not sensitive to lysozyme

Question 19

bacterial chromosome

Answer 19

a circular chromsome
compact dna
no nuclear membrane
called a nucleoid

Question 20

extreme halophiles

Answer 20

can survive

Question 21

archael cell growth

Answer 21

since they are prokaryotes they multiply by binary fission

Question 22

why cant many archaeal cells be grown in a lab

Answer 22

because we are not able to recreate the odd and extreme conditions they usually live

Question 23

archael metabolism

Answer 23

phototrophy
anaerobic
aerobic
or facultative anaerobes

Question 24

hyperthermophile

Answer 24

an organism that thrives in extremely hot environments

Question 25

methanogens

Answer 25

organisms that produce methane as a byproduct of metabolism in hypoxic conditions