chapter 16- origin and evolution of microbial life.pptx dimaporo

8/12/2019 Chapter 16- Origin and Evolution of Microbial Life.pptx Dimaporo

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Chapter 16Origin and Evolution of Microbial Life: Prokaryotes and Protists



Figure 16.1 Bacteria on a pin point



Earth formed 4.6 billion years agoEarly atmosphere: CO, CO2, N2, H2O, CH4, NH3

Very different from atmosphere todayLightening, volcanic activity, UV- much moreintense

Prokaryotes- fossils date 3.5bil yrs agoPrevalent in matsPhotosynthesis produces O2 in atmosphere

Organic chemicals- 3.9bil yrs ago- possibly fromenergized inorganic material (from UV orlightening)



Animals

Land plants

Ceno-zoic

Humans

Origin of solarsystem andEarth

Proterozoiceon

Archaeaneon

Prokaryotes

Atmosphericoxygen

Single-celledeukaryotes

Multicellulareukaryotes

Billions of years ago

1 4

2 3



Cocci Bacilli Spirochete



Figure 16.2B Gram-positive (purple) and gram-negative (pink) bacteria



Hypotheses of life’s origin 1- spontaneous generation- didn’t explain how life arose in thefirst place (Pasteur- maggots on meat)

2- comets and meteorites brought organic compounds to Earth3- (broken up into stages) 1 st- synthesis of organic molecules.2nd- formation of polymers from organic molecules

3rd- polymers replicate (primitive heredity). 4 th- polymers aggregate

having different characteristicsHeterotroph Hypothesis- conditions of primitive Earth producedorganic substances (which could then give rise to organisms)○ These organisms absorbed organic nutrients

○ Miller and Urey experiment produced amino acids○ Now disproved due to change in primitive atmosphere○ Now, underwater volcanoes and vents may have provided

chemical resources



Water vapor “Atmosphere”

Electrode

Condenser

CH 4

Coldwater

Cooled watercontainingorganicmoleculesH2O

“Sea”

Sample forchemical analysis



Monomers Formation of short RNApolymers: simple “genes”

G

G

C

C

U

U U

A

A

G G C U U U

C U

U

Assembly of acomplementary RNAchain, the first step inreplication of the

original “gene”

A C G U U

G



Stages in chemical evolutionOrganic molecules polymerized on hot rocks/clay○ Due to binding sites and metals that clay contained1st genetic material was RNA○ Replicated itself w/o assistance○ Ribozymes- RNA that acts as enzyme, aids in splicing and

polymerization○ RNA World- hypothetical period or evolution when RNA

served as genes and catalyst moleculeRNA could translate into protein (w/o ribosomes or

tRNA)Protein produced helped RNA replicate○ Lipid/protein spheres held RNA/polypeptide co- op’s Co- op’s grew and replicated ○ Evolved a single metabolism



Self-replication of RNA

Self-replicating RNA acts astemplate on which poly-peptide forms.

Polypeptide acts as primitiveenzyme that aids RNAreplication.

Polypeptide

RNA



Membrane

Polypeptide

RNA



Prokaryotes- bacteria

Smaller than eukaryotes, can live in extremeenvironments, live inside of us (digestive tract), arevery important.Come in sphere, rod and spiral shapes2 groups Bacteria and AchaeaBacteria- found in air, land and water, everywhere○ Covers skin, lining nose and mouth, fill digestive

tract○ Many bacteria are pathogens- disease-causing

agentLyme disease, staph, meningitis, syphilis

○ Koch’s postulate*



Archaea- thrive in extreme conditions (heat, salt,areas high in methane)

Ways of nourishment-○ Photoautotroph- sun and CO2○ Chemoautotroph- inorganic compounds and

CO2○ Most prokaryotes are heterotrophs**○ Photoheterotroph- sun and organic compounds

(obtain carbon from organic molecules, E fromsun)

○ Chemoheterotroph- Most abundant*- geteverything from organic compounds



Pili

C o l o r i z e d

T E M 1 6 , 0 0 0



Uses of bacteria Biological weaponsRecycle chemicals, clean up environment (oil spills)

Bioremediation- use of prokaryotes to clean up pollutionEukaryotes originated from communities of prokaryotesLived symbiotically (endosymbiosis)- gave rise to mitochondria and chloroplastsProtists- unicellular and some multicellular eukaryotesSome are photosyntheticHeterotrophs are called protozoaMore complicated than prokaryotes- have membrane bound nucleus and organelles

4 types:Protozoa- ingest food “animal like” Ex:amoebaSlime molds- have uni- and multi-cellular stages of life, heterotrophsUnicellular algae-photosyntheticMulticellular algae- “seaweed” - photosyntheticMulticellular life probably evolved by specialization of protist coloniesMulticellular life- arose about 1bil yrs ago and was aquatic until 500mil yrs ago



Rotatingspray arm

Rock bedcoated withaerobicbacteriaand fungi

Outflow Liquid wastes



Cytoplasm

Plasmamembrane

Ancestral prokaryote

Membrane infolding

Endoplasmicreticulum

Nuclearenvelope Nucleus

Cell with nucleus andendomembrane system

Photosyntheticprokaryote

Somecells

Aerobic heterotrophicprokaryote

Ancestral host cell

Endosymbiosis

Mitochondrion

Chloroplast

Mitochondrion

Photosynthetic eukaryotic cell



D i p l o m o n a d s

E u g l e n o z o a n s

D i n o f l a g e l l a t e s

A p i c o m p l e x a n s

C i l i a t e s

W a t e r m o l d s

B r o w n a l g a e

G r e e n a l g a e

P l a n t s

C l o s e s t a l g a l r e l a t i v e s o f p

l a n t s

R e d a l g a e

A n i m a

l s

F u n g i

A m o e b a s

C h o a n o f l a g e l l a t e s

C e l l u l a r s l i m e m o l d s

P l a s m o d i a l s l i m e m o l d s

D i a t o m s

Alveolates Stramenopila Amoebozoa

Ancestral eukaryote



Sources:http://en.wikipedia.org/wiki/Microorganism

https://www.google.com.ph/search?q=chapter+16+microbial+life+prokaryotes+and+protists+powerpoint&source=lnms&tbm=isch&sa=X&ei= http://ockerscience.wikispaces.com/file/view/LEH+Ch+16

+teacher.ppt http://faculty.tarleton.edu/nelson/public/Biology%20470/Ch.%2016%20Presentation.ppt http://projects.ecfs.org/pchurch/powerpointsCCe5/16_Lec

tures_PPT/16_Lectures_PPT.ppt

Researched byDimaporo, Janisah M.

http://en.wikipedia.org/wiki/Microorganism

https://www.google.com.ph/search?q=chapter+16+microbial+life+prokaryotes+and+protists+powerpoint&source=lnms&tbm=isch&sa=X&ei=7XYeU82nN82wiQe8q4HoBQ&ved=0CAcQ_AUoAQ&biw=1280&bih=587



http://ockerscience.wikispaces.com/file/view/LEH+Ch+16+teacher.ppt


http://faculty.tarleton.edu/nelson/public/Biology%20470/Ch.%2016%20Presentation.ppt


http://projects.ecfs.org/pchurch/powerpointsCCe5/16_Lectures_PPT/16_Lectures_PPT.ppt











http://en.wikipedia.org/wiki/Microorganism

chapter 16- origin and evolution of microbial life.pptx dimaporo

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