Lecture 1

Question 1

Who was the most important person as far as the history of plants and evolution of plants/ the eukaryotic cell?

Answer 1

Charles Darwin (1859)

Question 2

heterotrophs

Answer 2

cells that obtain their energy by consuming compounds produced by other sources (can be inorganic or organic)

Question 3

autotrophs

Answer 3

cells that produce organic compounds (energy source) (carbs, fats, proteins, etc) from simple inorganic materials

Question 4

photoautotrophs

Answer 4

harvest light energy to produce organic compounds

Question 5

chemoautotrophs

Answer 5

use chemical energy (CO2, H2, S)

Question 6

are photoautrvtrophs prokaryotic, eukaryotic, or both

Answer 6

both

Question 7

what are two characteristics of prokaryotes

Answer 7

they share similar light trapping pigments (chlorophyll, carotenoids, xanthophyll, etc) and secrete a cell wall

Question 8

when were only anaerobic bacteria existing on earth

Answer 8

3.8 bya

Question 9

when was the great oxygenation event / oxygen crisis

Answer 9

3.2 bya

Question 10

when was the earliest oxygen

Answer 10

~3.5 bya

Question 11

describe important characteristics of cyanobacteria

Answer 11

they are a primitive species still present in todays lineage (still exist)
they have a circular chromosome, JELLY COATING, cell wall, thylakoids, are photosynthetic

Question 12

why did the oxygen crisis happen

Answer 12

accumulation of cyanobacteria in the form of stromatolites producing a mass amount of oxygen as a waste product

Question 13

stromatolites

Answer 13

rocky mounds with layers (biofilms) of cyanobacteria aka blue-green algae in sediments

Question 14

what was the result of the accumulation of oxygen

Answer 14

oxidation of iron/ precipitation (think of iron rich layers of rock) and production of methane
overall effect was an increase in free oxygen

Question 15

what was the result of increase in free oxygen

Answer 15

buildup of ozone (O3) and O2 based respiration

Question 16

what is endosymbiogenesis the origin of

Answer 16

mitochondria and chloroplasts (separate events)

Question 17

describe endosymbiogenesis

Answer 17

A. an ancestral form evolved to have infolded membranes called invaginations.
B. an early eukaryote engulfed without digesting the prokaryote with the invaginations (origin of mitochondria)
C. an early eukaryote engulfed without digesting an autotrophic prokaryote (origin of plastids)

Question 18

what is secondary endosymbiosis

Answer 18

when a single celled eukaryote engulfs (without digesting) another eukaryote which has already undergone primary endosymbiosis

Question 19

what is a nucleomorph

Answer 19

a greatly reduced endosymbiont nucleus (the nucleus in the eukaryote which was engulfed)

Question 20

describe the symbiotic relationship between fungus and algae

Answer 20

three major forms: crustose, foliose, fruticose

- think fungi growing on a tree covered in algae

Question 21

describe the symbiotic relationship on the aerial roots of epiphytic orchids

Answer 21

the roots look green on the tips

Question 22

describe the symbiotic relationship zooxanthellae

Answer 22

• in reef building corals
• the plant system on the coral is what keeps it alive (bleaching of coral is when the symbiosis falls apart/ doesn’t exist)

Question 23

what are the characteristics of freshwater algae

Answer 23

• cyanelles (endosymbiotic cyanobacteria but they’re organelles)
• non-stacked thylakoids
• carboxysome-like bodies
• store polysaccharides (starch) in cytoplasm and not in chloroplasts
• reproduce by motile vegetative spores called zoospores

Question 24

what monophyletic supergroup does freshwater algae belong to

Answer 24

Archaeplastida

Question 25

describe UNICELLULAR green algae

Answer 25

• chlorophyta
• eukaryotic
• cup shaped chloroplast (looks like a string bean to me)
• have chla, chlb, carotenoids and xanthophyll
• starch grains in chloroplast (unlike freshwater algae which stores it in the cytoplasm)
• light responsive which is how it moves (using a flagella)
• prof described it as a plant-animal

Question 26

describe the colony form of green algae

Answer 26

• chlorophyta
• eukaryotic
• free living
• can form different structures (scenedesmus: in a line, hydrodictyon: water net, looks like a lattice, gonium: circular)