Plants 1 Lecture

Question 1

Where does photosynthesis originate?

Answer 1

Ancient cyanobacteria

Question 1

Great Oxidation Event

Answer 1

Cyanobacteria became numerous and extreme amounts of oxygen were released into the air. Lots of organisms died because of the great oxygenation event because they were not accustomed to large amounts of oxygen

Question 2

Primary Endosymbiosis

Answer 2

A eukaryotic cell engulfed a cyanobacterium that could do photosynthesis

Question 3

Evidence of primary endosymbiosis

Answer 3

• Chloroplast have their own DNA, that is circular(similar to that of cyanobacteria)
  -Peptidoglycan can be found in the cell wall of some chloroplast
  -Chloroplast have a double membrane(free-living at one point in time)

Question 4

What came first Mitchondria or the Chloroplast?

Answer 4

The mitochondria because all eukaryotes have a mitochondria but not all eukaryotes have a chloroplast

Question 5

How did chloroplast get into other lineages other than plants?
Evidence?

Answer 5

Secondary Endosymbiosis event: a eukaryote engulfed another eukaryote that contained a chloroplast.
Evidence: Chloroplast in other lineages have more than two membranes

Question 6

Photosynthesis Today

Answer 6

-Majority of photosynthesizes are in the ocean
- Phytoplankton do the majority of photosynthesis in the ocean

Question 7

Is Brown Algae a plant?

Answer 7

No

Question 8

Why is brown algae brown?

Answer 8

They contain carotenoids(accessory pigment)

Question 9

Brown Algae is a keystone species?

Answer 9

Brown algae(kelp) is a primary producer that feeds herbivores which then feed carnivores and omnivores. Without kelp there would be a trophic cascade

Question 10

Importance of red algae

Answer 10

-major photosynthesizer
-can be found deeper than brown and green algae due to having the ability to absorb blue light(blue light penetrates deeper into water)
- Red algae forms cancerous deposits outside of it cell walls that form large corralling structures that aid in reef support.