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Evolutionary Biology > Lesson 5: The origin of Microbial Life > Flashcards

Lesson 5: The origin of Microbial Life Flashcards

1
Q

What is the title of Lesson 5?

A

The origin of Microbial Life: Prokaryotes and Protists

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2
Q

This formation marks a time when photosynthetic bacteria were producing O2 that made the atmosphere aerobic.

A

Fossilized mats of prokaryotes

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3
Q

What do you call the fossilized mats of prokaryotes as a whole structure?

A

Stromatolites

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4
Q

What is the estimated date of when the planet earth formed?

A

4.6 or 4.5 BYA

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5
Q

The early atmosphere probably contained these six compounds that may have contributed to the formation of early life.

A

H20, CO, CO2, N2, CH4, O2

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6
Q

What were the three conditions thought to be intense during early earth that could have helped spark life?

A

Volcanic activity
Lightning
UV Radiation

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7
Q

Fossilized prokaryotes date back to how many years?

A

3.5 BYA

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8
Q

As early as 3.9 BYA, Life may have developed from what?

A

Non-living (abiotic) materials

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9
Q

How did life originate? State at least three hypotheses.

A

a. Small organic molecules must have appeared first

b.Probably happened when inorganic chemicals were energized by lightning or UV radiation

c.First polymers may have formed on hot rocks or clay.

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10
Q

The first polymers may have formed on hot rocks or clay. Which could have produced?

A

It could have produced polypeptides and short nucleic acids

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11
Q

This experiment showed that organic material could have arisen on lifeless earth.

A

Urey-Miller Experiment

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12
Q

The simulation of Urey-Miller has produced three significant substances. What are they?

A

Amino acids, sugars, and nucleotide bases.

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13
Q

In the concept of the first genetic material and enzymes, the first genes may have been what molecules?

A

RNA molecules

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14
Q

These enzymes could have catalyzed their own replication in a prebiotic RNA world.

A

Rybozymes

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15
Q

Ribozymes could have catalyzed their
own replication in a prebiotic RNA
world. What are the two steps?

A
  1. Formation of short RNA polymers (aka, simple genes) from monomers.
  2. assembly of a complementary RNA chain; the first step in the replication of the original gene.
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16
Q

State the interactive structure that probably preceded the first real cells.

A

Molecular cooperatives enclosed by membranes

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17
Q

These molecules might have acted as rough templates for the formation of polypeptides.

A

Self-replicating RNA

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18
Q

These structures may have protected some of the molecular cooperatives as they evolved rudimentary metabolism

A

Surrounding Membrane

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19
Q

Surrounding membranes may have protected some of these molecular co-ops as they evolved this basic form of metabolism.

A

rudimentary metabolism

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20
Q

These are the oldest Life-forms known to man.

A

Prokaryotes

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21
Q

These organisms remain the most numerous and widespread organisms on Earth today.

A

Prokaryotes

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22
Q

Prokaryotes are classified into two
domains; which are?

A
  1. Bacteria
  2. Archaea
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23
Q

The bases of prokaryote classification is based on what?

A

Nucleotide sequences and other features

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24
Q

The two main branches of prokaryotic evolution.

A

Archea and Bacteria

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25
T or F: Prokaryotes obtain nourishment in a variety of ways.
True
26
What are the prokaryotes that obtain carbon from CO2 and state two of their types;
Autotrophs; Photoautotrophs and Chemoautotrophs
27
These prokaryotes obtain carbon from organic compounds
Heterotrophs
28
These organisms were most likely the first cells. They obtain their energy from sulfur and iron compounds
Chemoautotrophs
29
T or F: Archaea thrive in extreme environments and in the ocean
True
30
Give three examples of extreme habitats where archaea thrive.
- anaerobic swamps - salt lakes - acidic hot springs - deep-sea - hydrothermal vents - animal digestive systems
31
This is a prokaryote structural feature that aids in locomotion.
Flagella
32
These structural feature help cells cling to surfaces
Pili
33
This structural feature allow certain bacteria to survive environmental extremes in a resting stage
Endospore
34
Many prokaryotes grow in what type of filaments?
linear filaments
35
These organisms photosynthesize in a plant-like way. They often bloom in polluted water.
Cyanobacteria
36
Bacteria as causative agents of diseases. Pathogenic bacteria can cause disease by producing what?
exotoxin and endotoxins
37
These are a set of criteria that can prove that bacteria are the cause of a disease
Koch's postulates
38
State two benefits of prokaryotes.
1. Bacteria as Biological Weapons. This is used in strategic or military applications during war or acts of terrorism. 2. Prokaryotes help recycle chemicals and clean up the environment. Prokaryotes that are chemoheterotrophs can help decompose chemical wastes. Helpful in solving environmental problems such as oil spills and toxic mine wastes.
39
What are the unique characteristics of archaea?
a. they are Extremophiles b. some are Methanogens
40
These are microorganisms that dwell in highly saline environments. However, some species merely tolerate a salty environment
Halophiles
41
These organisms thrive in very hot environments such that the genus Sulfolobus live in sulfur-rich volcanic springs as hot as 90oC
Thermophiles
42
These prokaryotes produce methane by reducing carbon dioxide. They live in moderate environments.
methanogens
43
State how methanogens produce methane.
They use carbon dioxide to oxidize hydrogen, thus releasing methane as a waste product.
44
Give an important application for methanogens.
Help decompose chemical wastes in sewage treatment facilities.
45
State the four Clades of Archaea
1. Euryarchaeota (broad) 2. Crenarchaeota (spring) 3. Kroarchaeota (young man) 4. Nanoarchaeota (dwarf)
46
The eukaryotic cell probably originated as a community of what organisms?
Prokaryotes
47
They are a group of all the eukaryotes that are not fungi, animals, or plants.
protists
48
The eukaryotic cell probably originated as a community of what organisms?
Prokaryotes
49
These cells evolved from prokaryotic cells more than 2 BYA
Eukaryotic cells
50
The nucleus and endomembrane system of eukaryotes probably evolved from what?
infoldings of the plasma membrane of ancestral prokaryotes
51
These organelles probably evolved from symbiotic prokaryotes that took up residence inside more giant prokaryotic cells.
Mitochondria and chloroplasts
52
These microorganisms were the ancestors of plants, animals, and fungi
Early protists
53
T or F: The taxonomy of protists is in a state of flux
True
54
Are a supergroup of protists that are defined by an asymmetrical appearance with a feeding groove that is “excavated” from one side
Excavata
55
Excavata subtypes that lack plastid.
Diplomonads.
56
What are the modified mitochondria found in diplomonads that lack a functional electron transport chain?
metosomes
57
These excavates have reduced mitochondria, known as hydrogenosomes
Parabasalids
58
Parabasalids have reduced mitochondria known as what?
hydrogenosomes
59
These excavates have a presence of a rod with either a spiral or a crystalline structure inside each of their flagella
Euglenozoans
60
What are the two best-studied types of Euglenozoans?
Kinetoplastids and euglenids
61
These euglenozoans have a single, large mitochondrion that contains an organized mass of DNA known as what?
kinetoplast
62
These excavates have a pocket at one end of the cell from which one or two flagella emerge.
Euglenids
63
T or F: Some euglenids are mixotrophs
True
64
Euglenids engulf prey by what process?
phagocytosis
65
This cladograph was proposed recently based on whole-genome DNA sequence analyses of protists.
SAR clade
66
What are the three major clades of protists;
stramenopiles alveolates rhizarians
67
Describe the flagella of stramenopiles
hairy and smooth
68
These protists have membrane-enclosed sacs just under the plasma membrane
alveolates
69
What are these membrane-enclosed sacs just under the plasma membrane?
alveoli
70
Photosynthetic protists are known as what?
algae
71
3 Types of photosynthetic protists (algae)
-Unicellular dinoflagellates -apicomplexans -ciliates
72
These are protists that ingest their food.
Protozoa
73
True or False: Protozoa include flagellates/ dino-flagellates and amoebas.
True
74
They are a large and varied group of protists named for their use of this long appendage to move and feed
ciliates
75
These protozoans have delicate, intricately SYMMETRICAL internal skeletons that are generally made of silica
Radiolarians
76
Forams are named for their porous shells, known as what?
tests
77
Foram tests consist of a single piece of organic material hardened with this mineral salt.
calcium carbonate.
78
A large group of amoeboid and flagellated protists that feed using threadlike pseudopodia
cercozoan
79
They consist of red algae and green algae along with land plants.
archaeplastida
80
A group of organisms that includes amoeba, animals, fungi non-amoeba protists that are closely related to animals and fungi
Unikonta
81
This clade includes many species of amoebas that have lobe- or tube-shaped pseudopodia, rather than the threadlike pseudopodia found in rhizarians
amoebazoans
82
Organisms that have both unicellular and multicellular stages
Cellular slime molds
83
Plasmodial slime molds form these brightly colored structures that contains many nuclei
supercells
84
They constitute a large and varied group of amoebozoans that have lobe- or tube-shaped pseudopodia
tubulinids
85
Free-living, parasitic amoebazoans.
entamoebas
86
They are extremely diverse group of EUKARYOTES that includes animals, fungi, and several groups of protists
Opisthokonts
87
T or f:Seaweeds are multicellular marine algae
True
88
These are multicellular photosynthetic organisms that lack the structural specializations of plants
seaweeds
89
Brown algae seem closely related to what single-celled algae?
diatoms
90
This algae is often classified in the plant kingdom
Green algae
91
Multicellular life may have evolved from colonial protists. Meaning?
Multicellularity evolved independently many times.

Evolutionary Biology (6 decks)

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