Topic 10

Question 1

How much do prokaryotes contribute to global biomass?

Answer 1

about 14%, second only to plants

because are highly adaptable and can be found in diverse environments

Question 2

Prokaryotic Cell Walls

Answer 2

• Call wall that maintains shape and provides protection
• Contains peptidoglycan, a network of sugar polymers cross-linked by short peptides

Question 3

Capsule

Answer 3

A sticky layer of polysaccharides or proteins that help prokaryotes stick to surfaces and each other, as well as protect from pathogenic bacteria

Question 4

Fimbriae

Answer 4

Short, hair-like structures that help prokaryote cells adhere to surface

Question 5

Pili

Answer 5

Longer hair-like structures that allow for the exchange of DNA between prokaryotic cells, enhancing genetic variation.

Question 6

Endospores

Answer 6

Metabolically inactive forms in prokaryotes that can survive extreme conditions for long periods that protect cells from heat, chemicals, radiation, and malnutrition

Question 7

Motility and Prokaryotic Success

Answer 7

Half of prokaryotes are motile and often use flagella for movement in response to environmental stimuli

Question 8

Binary Fission

Answer 8

A form of asexual reproduction in prokaryotes resulting in genetically identical copies of the original cell, producing and separating cells in the same step (different from meiosis) very quickly in a short time

Question 9

3 Factors that Contribute to Prokaryote Genetic Diversity

Answer 9

Rapid reproduction, mutations, and genetic recombination

Question 10

Horizontal Gene Transfer

Answer 10

When genetic recombination occurs between individuals from different species

Question 11

How can Prokaryotes exchange genetic material?

Answer 11

Transformation, transduction, and conjugation

Question 12

Transformation

Answer 12

Where bacteria take up and integrate DNA from their external environment through uptake of DNA fragments or plasmids released from dead bacteria

Question 13

Transduction

Answer 13

Transfer of DNA via bacteriophages (viruses that infect bacteria)

Question 14

Conjugation

Answer 14

Direct transfer of DNA between cells via a pilus where donor cell transfers DNA to a recipient cell unidirectionally.

When plasmids are frequently transferred

Question 15

Metabolic Diversity

Answer 15

Being able to exist in a wide range of environments because of a wide range of ways to obtain energy and carbon

Question 16

4 Major modes of nutrition of Energy and Carbon Sources

Answer 16

Photoautotrophy, Chemoautotrophy, Photoheterotrophy, and Chemoheterotrophy

(understand the terms by breaking them down)

Question 17

Obligate aerobes

Answer 17

Prokaryotes that rely on O2 for cellular respiration

Question 18

Obligate anaeropes

Answer 18

Prokaryotes inhibitied by O2 and instead use fermentation or anaerobic respiration for energy

Question 19

Faculative anaerobes

Answer 19

Prokaryotes that can switch between using O2 and not using it, depending on its availability

Question 20

Biological Nitrogen fixation

Answer 20

A process of converting atmospheric nitrogen (N2) into ammonia (NH3)

Possible in some prokaryotes including methanogens

Question 21

Bacteria

Answer 21

Most of the well-known prokaryotic species that is incredibly abundant and can be found in nearly every habitat

Question 22

Proteobacteria

Answer 22

Large and metabolically diverse group of gram negative bacteria, some include pathogens

Question 23

Chlamydias

Answer 23

Obligate intracellular parasites that live only in animal cells, depended on a host for survival and reproduction, lack peptidoglycan (stain gam-negative
Ex) Chlamydia trachomatis (common STI)

Question 24

Spirochetes

Answer 24

Helical heterotrophs known for their spiral shape and cork-screw movement that live as free-living bacteria or parasites

Question 25

Cyanobacteria

Answer 25

The only prokaryotes that, like plants, can generate oxygen through photoautotrophy

Question 26

Archaea

Answer 26

A domain often found in extreme environments that shares traits with both bacteria and eukaryotes and cell walls that do not contain peptidoglycan, which makes them resistant to antibiotics that target bacterial cell walls

Question 27

Methanogens

Answer 27

obligate anaerobes that thrive in anoxic environments, such as swamps, marshes, and digestive tracts that produce methane as a waster metabolite

Question 28

Extreme Halophiles

Answer 28

Organisms in the Archaea domain that are found in highly saline environments

Question 29

Prokaryote Crucial Roles in Biosphere

Answer 29

Oxygene production, nitrogen fixation, and the recycling of chemical elements

Question 30

Function of Chemoheterotrophic Prokaryotes

Answer 30

Decomposers, breaking down dead organisms and wastes to enhance the availability of essential nutrients such as nitrogen, phosphorus, and potassium