Life in Increasing Complexity #11 Flashcards
What are the major groups in SAR?
Stramenopiles
Alveolates
Rhizarians
What are the key characteristics of the major groups in SAR
includes the most important photosynthetic organisms, originated by secondary endosymbiosis when a heterotrophic protist engulfed a red alga
What is the importance of plants in the development of terrestrial ecosystems?
primary producers
major increases in O2
shielded organisms from mutagenic effects of solar radiation
What is the evolution of red & green algae in endosymbiosis?
capable of asexual reproduction & cholorophytes
What does secondary endosymbiosis mean?
red/ green algae engulfed by other eukaryotes
What groups in SAR evolved from secondary endosymbiosis?
stramenopiles
avelotates
evacavata
What are the group names and relationships of the monophyletic group that contains algae & land plants?
red algae/ chlorophyte (green algae)/ plants - cyanobacterium
What are the characteristics of red algae & the example of the sexual life cycle?
pigment, “phycoerythrin” masks the green of chlorophyll, capable of asexual reproduction
ex: reproduction
What are the characteristics of green algae & the example of the sexual life cycle?
“fake group”, mutualisms with other protists, sponges, cnidarians
ex: chlorophytes (sexual & asexual reproduction)
What is the group that plants likely evolved from?
terrestrial unicellular chlorophytes
What are the characteristics that green algae share with plants?
- similar organization of chloroplasts
- contain chlorophyll a and b, along with similar accessory pigments
- some other cellular morphology
What is one of the major barriers to plant colonization of land?
sporopollenin layer prevented zygote desiccation
How did plants overcome the major barriers to plant colonization of land?
land plants fundamentally changed the terrestrial ecosystem and paved the way for other life forms
