25Prok

Information about 25Prok

Published on October 9, 2007

Author: Heng

Source: authorstream.com

Content

Prokaryotes:  Prokaryotes Domain Bacteria Domain Archaea Prokaryotes:  Prokaryotes The most common shapes are spheres, rods and helices, and most are 1-5um Outside their cell membranes, most bacteria posses a cell wall containing peptidoglycans Gram-positive bacteria have simpler walls with more peptidoglycan Gram-negative bacteria have more complex walls with less peptidoglycan Pili are appendages used to adhere to other surfaces About ½ are motile due to the presence of flagella Remember prokaryote genetics: plasmids, binary fission, transformation, conjugation, transduction and mutation Most prokaryotes are in Domain Bacteria The first prokaryotes classified as Domain Archaea are known as extremophiles and live in extreme environments Methanogens live in marshes and swamps where O2 is absent, produce methane (“marsh gas”) as a waste product Extreme halophiles live in high salt environments (Great Salt Lake, Dead Sea) Extreme thermophiles live in very hot environments (deep sea thermal vents) The most common shapes of prokaryotes:  The most common shapes of prokaryotes Orange and yellow colonies of “heat-loving” prokaryotes in the hot water of a Nevada geyser:  Orange and yellow colonies of “heat-loving” prokaryotes in the hot water of a Nevada geyser Prokaryote Metabolism:  Prokaryote Metabolism Prokaryotes can be placed in four groups depending on how they take in carbon and obtain energy Photoautotrophs: photosynthesize, use sunlight energy to convert CO2 into organic compounds (e.g., carbohydrates) Chemoautotrophs: don’t use sunlight as a source of energy, instead they use H2S, NH3 or other inorganic molecules to convert CO2 into organic compounds Photoheterotrophs: use sunlight as the energy source, but must obtain their carbon in an organic form (i.e., they can’t use CO2) Chemoheterotrophs: get both carbon and energy from organic compounds (this is what humans do!) Metabolism:  Metabolism Most prokaryotes are chemoheterotrophs Saprobes (decomposers) absorb nutrients from dead organic matter (important step in nutrient cycling in an ecosystem) Parasites absorb the nutrients from the body of a living host (may also participate in mutualism and commensalism) Some prokaryotes can use atmospheric nitrogen (N2) and convert it to NH4+ in a process called nitrogen fixation Obligate aerobes require O2 to live Obligate anaerobes are poisoned by O2 Facultative anaerobes use O2 when it is available and undergo fermentation when it is not Prokaryotes have specialized membranes for photosynthesis and respiration Specialized membranes of prokaryotes:  Specialized membranes of prokaryotes

Related presentations


Other presentations created by Heng

Cattle Farming
28. 12. 2007
0 views

Cattle Farming

1920 2000 Presidents Review
13. 04. 2008
0 views

1920 2000 Presidents Review

07 Messaging
30. 03. 2008
0 views

07 Messaging

SITE motivation
27. 03. 2008
0 views

SITE motivation

Hands On Session
14. 03. 2008
0 views

Hands On Session

Key Messages
05. 03. 2008
0 views

Key Messages

courseweb
24. 02. 2008
0 views

courseweb

interim01 presentation
20. 02. 2008
0 views

interim01 presentation

UofODay2007
07. 01. 2008
0 views

UofODay2007

Rivkin Fish
07. 01. 2008
0 views

Rivkin Fish

lecture 1
02. 10. 2007
0 views

lecture 1

Sikhism and Baisakhi
26. 11. 2007
0 views

Sikhism and Baisakhi

Plant Reproduction Chapter41
12. 12. 2007
0 views

Plant Reproduction Chapter41

schoff
25. 10. 2007
0 views

schoff

Watkins
26. 10. 2007
0 views

Watkins

chap 18 web
26. 10. 2007
0 views

chap 18 web

After the Fall of Rome
29. 10. 2007
0 views

After the Fall of Rome

tropopause folding ialongo
30. 10. 2007
0 views

tropopause folding ialongo

tw gannon eb XML tech overview
07. 11. 2007
0 views

tw gannon eb XML tech overview

Rodos
30. 10. 2007
0 views

Rodos

AUC DV2003 Woo2
19. 11. 2007
0 views

AUC DV2003 Woo2

Ken
23. 11. 2007
0 views

Ken

Greco Persian Wars
14. 12. 2007
0 views

Greco Persian Wars

columbia dvp
28. 12. 2007
0 views

columbia dvp

The Neanderthal Enigma
31. 12. 2007
0 views

The Neanderthal Enigma

RobertTwilley
03. 01. 2008
0 views

RobertTwilley

AnalysisModeltalk 01Nov05
29. 10. 2007
0 views

AnalysisModeltalk 01Nov05

MTG Benefits
08. 11. 2007
0 views

MTG Benefits

shraiman lecture2 boulder 2
04. 01. 2008
0 views

shraiman lecture2 boulder 2

01 13 05 Andersonian
15. 11. 2007
0 views

01 13 05 Andersonian

TexasVulnerable
30. 12. 2007
0 views

TexasVulnerable

pwps merrell ann phare
28. 12. 2007
0 views

pwps merrell ann phare

DFASBRACAllHandsDec15
30. 10. 2007
0 views

DFASBRACAllHandsDec15

07 15 WMWW Romans 8 Intro
31. 10. 2007
0 views

07 15 WMWW Romans 8 Intro

PIPPresentation
05. 12. 2007
0 views

PIPPresentation

lpgassafety
06. 11. 2007
0 views

lpgassafety

April 11 2007 Presentation
13. 12. 2007
0 views

April 11 2007 Presentation

vcmeeting 2005 12 07
01. 10. 2007
0 views

vcmeeting 2005 12 07

Risa ERF 2005
03. 01. 2008
0 views

Risa ERF 2005

Illum
17. 12. 2007
0 views

Illum

BilgMuh tanitim
30. 11. 2007
0 views

BilgMuh tanitim

04 Technopole Brest
14. 11. 2007
0 views

04 Technopole Brest

GA PRGTIPGTE07Norman
29. 12. 2007
0 views

GA PRGTIPGTE07Norman

childsafeysor
25. 12. 2007
0 views

childsafeysor

ekleziologia
21. 11. 2007
0 views

ekleziologia

011116 dg coord price
30. 10. 2007
0 views

011116 dg coord price