week 2: lab 4 (Microbial phototrophs)

Question 1

what are the major groups of microbial phototrophs?

Answer 1

-algae
-cyanobacteria

Question 2

Prokaryotic vs eukaryotic :

Answer 2

• Prokaryotes are always unicellular, DNA is stored in the cytoplasm of prokaryotes.
• Eukaryotes are often multi-celled, 100 -10k times larger than prokaryotic cells, more complex, and DNA is stored within the nucleus.

Question 3

what are cyanobacteria classified as?

Answer 3

-plants
-protozoa
-bacteria

Question 4

Are cyanobacteria prokaryotic or eukaryotic and why?

Answer 4

• Prokaryotic (their DNA is contained within a region of the cell called a nucleoid), they lack a nucleus and double membrane-bound organelles.

Question 5

Where do cyanobacteria derive their energy from?

Answer 5

• utilize sunlight to make energy molecules and they use Chlorophyll a, to capture light energy
• Take in CO2, light, and water → produce O2 and sugar molecules (glucose)

Question 6

Major characteristic of cyanobacteria:

Answer 6

• prokaryotic, aquatic, and photosynthetic

Question 7

Cyanobacteria morphology:

Answer 7

• Akinete
• Heterocyst
• Trichomes
• Sheaths

Question 8

Cyanobacteria exist as single cells such as either:

Answer 8

• filamentous or ribbonlike

Question 9

Cyanobacteria dies when:

Answer 9

• nutrient level decrease

Question 10

Breakdown of dead cyanobacteria can cause:

Answer 10

overabundance can lead to toxic blooms causing:
- Respond to environmental nutrient shifts
- Agricultural and sewage run-off, negatively impacts lakes and rivers
- Respiratory and gastrointestinal problems

Question 11

why are cyanobacteria beneficial in agriculture?

Answer 11

• Nitrogen fixation
• Builds macromolecules that can be used by the cells

Question 12

where are algae found and is it prokaryotic or eukaryotic?

Answer 12

-eukaryotic
-can be unicellular (single celled) or
multicellular (2 or more cells)
-Found in freshwater, saltwater, and soils

Question 13

algae are characterized by?

Answer 13

-Contain photosynthetic pigments: Chlorophyl a
-Reproduction methods
-Motility: flagella
-Cell wall composition: Cellulose or silica dioxide

Question 14

Certain algae are associated with large blooms such as:

Answer 14

-Toxic
- bioluminescence

Question 15

environmental significance of cyanobacteria:

Answer 15

-important organisms for the health and growth of many plants
-can convert inert atmospheric nitrogen into an organic form, such as nitrate or ammonia.

Question 16

clinical significance of cyanobacteria:

Answer 16

…

Question 17

environmental significance of algae:

Answer 17

forming the energy base of the food web for all aquatic organisms (they are the basis for food chains)

Question 18

clinical significance of algae:

Answer 18

common additive in pharmaceutical products

Question 19

what makes them appear green?

Answer 19

Chlorophyll a