Lecture 27

Question 1

4 basic essentials

Answer 1

oxygen, water, nutrients, temp. reg

Question 2

heterotrophs

Answer 2

consume food and O2, produce CO2

Question 3

autotrophs

Answer 3

carbon reduction
consume Co2 and produce food / O2

Question 4

evidence for life on earth

Answer 4

chemical disequilibrium

redox cycles have planetary consequences

Question 5

if life was not present, all oxygen and methane…

Answer 5

would be consumed by chemical reactions

Question 6

cyanobacteria

Answer 6

devel. oxygenic photosynthesis ~2.5 billion years ago

origin of chemical disequilibrium

Question 7

primary production

Answer 7

microbes.
at center of the earth system
nutrient cycling
GHG production / consumption

Question 8

marine carbon cycle

Answer 8

driven by photosynthetic oceanic protists

Question 9

historical roots of microbiology

Answer 9

medicine / food - pure cultures - medical / industrial microbio

agriculture - study of whole ecosystem - microbial ecology (enviro. micro)

Question 10

methanogens

Answer 10

produce methane

Question 11

Winogradsky columns

Answer 11

O2 on top H2S sinks

oxygen, light and nutrients gradient

aerobic –> anaerobic

Question 12

in absence of oxygen, respiration…

Answer 12

use sulfate .. waste product = sulfide