Lect 30 - microbes & energy flow - fuelling microbes and whol ecosystems

Flashcards covering key concepts from the lecture, including microbial ecology, redox reactions, trophic groups, and energy harvesting.

Microbial ecology

The study of the interrelationships among microorganisms and their environment.

Population

Individual microbial cells of a species proliferate.

Communities

Populations interact/communicate.

Breaking down a macromolecule can lead to:

To reuse components for building new molecules and to power cellular processes

External electron donor

H2S donates electrons → becomes S

Electron carrier

NADP+ is reduced to NADPH2 → NADPH2 acts as electron carrier transferring electrons to other molecules

Electron acceptor

CO2 is reduced by electrons from NADPH2 → produces (CH2O)n

Energy

Energy harvested from the environment is converted to a ‘local currency’ inside the cell.

NAD+/NADH

NAD+ and NADH facilitate redox reaction without being consumed → they are recycled

Autotrophs

Primary producers; Fix CO2; Self-sufficient, do not require carbon

Heterotrophs

Decomposers; Need fixed carbon → cannot use CO2 directly; Dependent on primary producers

Chemotrophs

Use chemical energy from either C compounds (organic) or Non-C compounds (inorganic)

Phototrophs

Use solar energy

Light

Photosynthetic pigments have complementary absorption spectra.

Light = common resource

Avoid competition by tuning their antenna (light-harvesting structure) to different wavelength

Energy Harvesting

If one source of energy is missing, there must be another one to sustain life.