Prokaryotes and protists

Question 1

Microorganisms (Microbes)

Answer 1

residing in and on your body outnumber your own cells.

Question 2

Disruption of our microbial communities can:

Answer 2

– increase our susceptibility to infectious diseases
– contribute to chronic conditions like asthma, allergies, irritable bowel syndrome, Crohn’s disease, Parkinson, autism.

Question 3

Prokaryotes

Answer 3

-Oldest cell type
-Small and simple
-Lack nucleus
-Lack organelles
-single-called

Question 4

True or false, Prokaryotic cells are smaller than eukaryotic cells.

Answer 4

True

Question 5

True or false, collective biological mass (biomass) of prokaryotes is
at least 10 times that of all eukaryotes.

Answer 5

True

Question 6

True or false, Prokaryotes have an immense impact on the environment and on our health.

Answer 6

True

Question 7

What are two very different kinds of prokaryotes?

Answer 7

They are classified in the domains Archaea and Bacteria.

Question 8

Three of the most common prokaryotic cell shapes are:

Answer 8

1. Spherical - cocci,
2. Rod-shaped -bacilli,
3. Spiral prokaryotes of two types:
   – Relatively short and rigid cells called spirilla
   – Longer and more flexible cells called spirochetes.

Question 9

True or false, Almost all prokaryotes have a cell wall.

Answer 9

True

Question 10

Prokaryotes can be classified by:

Answer 10

shape and by reaction to a Gram stain.

Question 11

Gram-positive bacteria

Answer 11

have simpler walls with a relatively thick layer of a unique material called peptidoglycan.

Question 12

True or false, The walls of gram-negative bacteria stain differently.

Answer 12

True

Question 13

Other features for Prokaryotes:

Answer 13

may include a sticky capsule, flagella, or fimbriae.

Question 14

Prokaryotes (bacteria and archaea)reproduction

Answer 14

reproduce by binary fission

Question 15

The division of on cell reproduce what?

Answer 15

reproduces the entire organism

Question 16

binary fission

Answer 16

The chromosome replicates (beginning at the origin of replication), and two daughter chromosomes move apart

Question 17

pinches inward, dividing the cell into two

Answer 17

Plasma membrane

Question 18

What forms endospores?

Answer 18

Some prokaryotes form endospores that remain dormant through harsh conditions.

Question 19

What does dormant survival forms of?

Answer 19

Forms of bacteria

Question 20

dormant survival form of bacteria resistant to?

Answer 20

– high temperatures
– most disinfectants
– low level radiation
–drying.

Question 21

What can survive thousands of years until environmental stimuli trigger germination?

Answer 21

Endospores

Question 22

Anthrax (Bacillus anthractis)

Answer 22

common soil bacteria; can be deadly

Question 23

Tetanus (Clostridium tetani)

Answer 23

common in the environment, toxin released by the bacteria can cause severe muscle spasms.

Question 24

Botulism (Clostridium botulinum)

Answer 24

common in soil and water; spores can be in improperly canned food, paralyzing.

Question 25

True or false, Prokaryotes exhibit much more nutritional diversity than eukaryotes.

Answer 25

True

Question 26

Two sources of energy can be used by prokaryotes.

Answer 26

– Like plants, prokaryotic phototrophs capture energy from sunlight. – Prokaryotes called chemotrophs harness the energy stored in chemicals.

Question 27

Prokaryotes attach to surfaces and form highly organized biofilm communities that are difficult to eradicate, causing—

Answer 27

both medical and environmental problems – or benefits.

Question 28

Biofilms

Answer 28

– protection from infection – Hard to eradicate

Question 29

Microbiome

Answer 29

– Immense effect on health – Provides micro-nutrition – Possible linked to SOME forms of autism, asthma, obesity, gluten sensitivity – Aggresion in coyotes (fusobacterium) – Lack of biodiversity affects our health, the environment – Immensely important role in agriculture – release and provide microcnutrients to plants – Re-establishment of native landscapes in part dependent on the microbiome

Question 30

Bioremediation

Answer 30

is the use of organisms to remove pollutants from soil, air, or water.

Question 31

True or false, Prokaryotes are often used for bioremediation, including in sewage treatment facilities.

Answer 31

True

Question 32

• Prokaryotes are:

Answer 32

– the largest biomass – Very diverse – By enlarge useful and essential for our ecosystem and health

Question 33

True or false, Advances in molecular genetics revealed that many prokaryotes are more closely related to eukaryotes than to other prokaryotes.

Answer 33

True

Question 34

the first major split in the history of life was the divergence of…..

Answer 34

Bacteria, and later divergence separated the domains Archaea and Eukarya

Question 35

True or false, Some of the main differences among the three domains involve the cellular machinery for gene expression

Answer 35

True

Question 36

Domain Archaea includes

Answer 36

– extreme halophiles (“salt lovers”), – extreme thermophiles (“heat lovers”), and – methanogens, which thrive in anaerobic conditions

Question 37

True or false, Sometimes archaea are referred to as “extremophiles.”

Answer 37

True

Question 38

VIRUS

Answer 38

consists of either DNA or RNA, that is protected by a protein/ membrane coat called a CAPSID.

Question 39

Viruses range in size

Answer 39

from 20 nanometers (nm) – 250 nanometers (nm) If a cell was the size of your classroom, then an average virus would be the size of a softball.

Question 40

Viruses affect bacteria, plants, animals.

Answer 40

Viruses cause colds, flu, warts and diseases such as measles, AIDS and cancer.

Question 41

True or false, not all viruses cause disease

Answer 41

True

Question 42

True or false, not all viruses are harmful to humans.

Answer 42

True

Question 43

Why the world needs viruses to function Key to ecosystems

Answer 43

• Phages control the populations of bacteria -> kill about 50% of bacteria each day • Some viruses are critical to the health of coral reefs • Some viruses allows infected plants to deter aphids

Question 44

Why the world needs viruses to function Protective to human health

Answer 44

• Some viruses may provide immune benefits • 8% of our genome is virally derived! • Phage therapy • Oncolytic viruses can specifically kill cancer cells • delivery of gene therapy, vaccines

Question 45

Incredibly important in evolution/ exchange of genes

Answer 45

• Bacterial evolution – pathogenic E.coli – shiga- toxin producing E. coli • Genes linked to the ability to have live births were introduced by ancient retroviruses that infected our ancestors more than 130 million years ago.

Question 46

Protists

Answer 46

Protists are mostly unicellular eukaryotes that are found in a variety of aquatic or moist habitats.

Question 47

Protists may be:

Answer 47

– autotrophic, called algae – heterotrophic, informally called protozoans, or – mixotrophic. Mixotrophs are capable of photosynthesis and heterotrophy.