Lecture 2: Plants, Chloroplasts, Lineage

Primary endosymbiosis states that eukaryotic chloroplast orginate from what?

symbiotic cyanobacteria

Walk me through the process of primary endoysmbiosis

1. ancestral eukaryote eats photosynthetic bacteria

2. pinches off some cyanobacteria and failed to consume it

3. now eukaryote and cyanobacteria symbiosis occurs and exist as one.

what is secondary endosymbiosis

ancestral eukaryote (host cell) eats another ancestral eukaryote that has already consumed cyanobacteria (chloroplast containing cells)

what is the phylogenetic definition of plants (plantae)?

“Plants” are photosynthetic eukaryotes with a chloroplast that has two outer membranes, resulting from primary endosymbiosis

Red Algae True or False (Give me full sentences):

1. Have cellulose walls

2. Have chlorophyll a and chlorophyll b

3. all red algae or single celled organisms

4. cell walls contains calcium carbonate

1. True, have cellulose walls

2. False, only have chlorophyll a

3. false, red algae can be single-celled or multi-cellular

4. true, cell walls contain calcium carbonate

True or false: green algae are the earliest branching green plants.

true

What are the 3 things all “green plants” have?

1. derived from primary endosymbiosis

2. has chlorophyll a and b

3. store carbs as starch

what makes up the streptophyte clade?

some green algae lineages and land plants

define phragmoplast

a plant cell specific structure that forms during late cytokinesis

define plasmodesmata

channels that bridge and penetrate the rigid cell walls of adjacent plant cells

what does phragmoplasts and phycoplasts have in common?

microtubule structures that guide cell division (cytokinesis) in plants

most ___ have plasmodesmata

streptophytes

what clade typically has phragmoplasts in their species

streptophytes

phycoplast vs phragmoplast orientation

1. phyocoplasts a vertical microtubules

2. phragmoplasts are horizontal microtubules

define parenchyma

the basic tissue type in the streptophytes with cells linked by plasmodesmata 

define isogamy and oogamy

1. Isogamy is the fusion of gametes that are identical in size and shape.

2. Oogamy is the fusion of gametes that are completely different. The female gamete (egg) is large and non-motile, while the male gamete (sperm) is small and motile.