BIOL10005 Lecture Notes - Lecture 18: Chlorophyta, Chlorophyll, Cell Wall
29 Jun 2018
School
Department
Course
Professor
LECTURE 18 - Photosynthetic (pigmented) Protist
Protista:
Diverse, simplest eukaryotic cell
In term of how they get their food:
oProducers
oConsumers
oAbsorbers and recyclers of dead, decaying things
Phylogeny
oBranches = relationships
oShows relationships between organisms (evolutionary history)
oConstructing phylognies:
Construct branches via the shared, derived characteristics
Monophyletic group: having 1 origin/nest (i.e. common ancestor)
Define true relationships
More closely related to each other
Paraphyletic group:
i.e. two nests
Absence of some character
Not useful --> can't talk r/ship or evolution
Protista = paraphyletic group
oWhat's left over of eukaryotic cells after removal of fungi, plants, animals
oCan't talk about evolution of protist
oCan break protista into mini monophyletic group
Not enough info to break them up properly
Primary producers:
Possess chloroplast & pigments
All eukaryotic has mitochondria
But protista + plants captured chloroplast as well
oPrimary endosymbiosis: eukaryotic cell capturing prokaryotes
Organelle that's captured = double membrane
Key evidence for endosymbiotic origin of mitochondria and chloroplasts:
Circular genome like bacterial
Smaller bacterial-type ribosomes
Organelle genome is similar to those of bacteria
Still integrate into cell machinery
Divide similar to binary fission
Capture of mitochondria first then chloroplast (cyanobacteria)
oCapture of chloroplast: occurred twice not once
HOW OTHER PHOTOSYNTHETIC ORGANISMS GET CHLORO: SECONDARY ENDOSYMBIOSIS:
Engulf eukaryotic cell with chloroplast
oRed or green algae
Occurred many times --> results in enormous diversity --> protistan pirates
Sometimes, the host cell retains chloroplast + other shit (i.e. remnant nucleus or
nucleomorph)
PRIMARY VS SECONDARY SYMBIOSIS:
find more resources at oneclass.com
find more resources at oneclass.com
Document Summary
In term of how they get their food: o o. Consumers: absorbers and recyclers of dead, decaying things. Monophyletic group: having 1 origin/nest (i. e. common ancestor) Not useful --> can"t talk r/ship or evolution. Protista = paraphyletic group: what"s left over of eukaryotic cells after removal of fungi, plants, animals o o. Not enough info to break them up properly. But protista + plants captured chloroplast as well o. Key evidence for endosymbiotic origin of mitochondria and chloroplasts: Organelle genome is similar to those of bacteria. Capture of mitochondria first then chloroplast (cyanobacteria: capture of chloroplast: occurred twice not once. How other photosynthetic organisms get chloro: secondary endosymbiosis: Occurred many times --> results in enormous diversity --> protistan pirates. Sometimes, the host cell retains chloroplast + other shit (i. e. remnant nucleus or nucleomorph) Primary: engulfing prokaryote, gene transfer from chloroplast to nucleus. Secondary: genes from chloroplast and nucleus = transferred to host nucleus: chloroplast: more than two membranes (3-4)
