Chapter 2
Differences in Proportions of C, N, P
Central Dogma--Genetics
mRNA
the length of mRNA molecules varies
only certain genes in a genome need to be expressed, depending on cell specialization and environment
not all genes are transcribed and translated
if a cell needs to produce a lot of a certain protein, then many copies of the required mRNA are created
ribosomal complex
directs translation
formed of proteins and structural RNA molecules
cellular structures
ribosomes
with increased growth rate, proportion of biomass made up by RNA increases
numerous in cells, especially fast-growing ones
membranes/walls
membrane
composed of phospholipids
acts as permeability barrier
old school way of grouping prokaryotes: composition of cell's PMs and/or cell walls
gram-positive
gram negative
external structures
pili
flagella
most open ocean prokaryotes LACK flagella
in some cases, only 5% of oceanic bacteria are motile
import NON-flagellated examples:
SAR11
Prochlorococcus
Extracellular Polysaccharides (EPS)
quorum sensing
impact on elemental proportions