L7 Plants Flashcards
Evolution of Eukaryotes
What is the endosymbiotic event that has led to the origin of mitochondria in Eukaryotes?
key words: lateral transfer, MRCA, eukaryotes
- Lateral transfer of proteobacteria into a eukaryotic cell
- Occuring* prior* to MRCA of eukaryotes because all eukaryotes have a mitochondria
**Evolution of Eukaryotes **
What is the endosymbiotic event that has led to the origin of chloroplast in Eukaryotes?
key words: lateral transfer, MRCA, eukaryotes
Lateral transfer of cyanobacteria into a eukaryotic cell
Occuring **after ** MRCA of eukaryotes because not all eukaryotic cells have a chloroplast
**Evolution of Eukaryotes **
What evidence do we have of endosymbiosis of the origin of mitochondria?
Human Mitochondrial DNA (MtDNA) is phylogenetically within proteobacteria
**Evolution of Eukaryotes **
What evidence fo we have of endosymbiosis of the origin of chloroplast?
key word: phylogeny, DNA
Corn chloroplast DNA is phylogentically within cyanobacteria
**Evolution of Eukaryotes **
What mechanism allowed for Eukaryotes to gain the ability to photosynthesize across the Tree of Life?
key word: secondary endosymbiosis
Secondary endosymbiotic events where a chloroplast-containing eukaryote was engulfed by a non-chloroplast containing eukaryote
Allowed for chloroplast to be distributed across Tree of Life
** Evolution of Land Plants **
Describe the phylogentic relationship and events between green algae and land plants
key words: monophyletic, paraphyletic, nested, ancestral state, primary endosymbiosis
- green algae are paraphyletic whereas green plants are monophyeltic
- land plants (embryophytes) are nested or are evolutionary derived from green algae
- All plants are derived a singular primary endosymbiotic event
** Evolution of Land Plants **
What is the ancestral state of all land plants?
Aquatic because derived from aquatic green algae!
** Evolution of Land Plants **
What are the major evolutionary challenged faced by plants while colonizing terrestrial / land habitats?
- Dessication (drying out)
- Growing larger / development of vascular systems
- Moving water and nutrients throughout their system
- Intercepting sunlight
** Evolution of Land Plants **
What are some ways a plant’s life cycle differs from our life cycle?
key words: haploid, diploid, mitosis, meosis gametophyte, sphorophyte
- Dominant haploid stage, where diploid stage depends on haploid stage
- gametes produced via mitosis
- multicellular haploid (2N) and diploid (2N) stages
** Evolution of Land Plants **
What is the haploid stage of a plant called?
Gametophyte
** Evolution of Land Plants **
What is the diploid stage of a plant called?
Sporophyte
** Evolution of Land Plants **
What was the major switch in the life cycle of land plants compared to Byrophytes and why was it important?
key words: life cycle, dominant stage, haploid, diploid, vascularization
Land plants have a dominant diploid (sporophyte) stage which allowed them to develop a vascular system on land
** Evolution of Land Plants **
How did land plants evolve to prevent dessication and what problem did it introduce?
Waxy cuticle allowed land plants to not dry out but hindered gas exchange
** Evolution of Land Plants **
What traits did land plants evolve to allow for smooth gas exchange despite waxy exterior?
- Stomata
- Guard cells
