Prokaryotes and protists Flashcards

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1
Q

Microorganisms (Microbes)

A

residing in and on your body outnumber your own cells.

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2
Q

Disruption of our microbial communities can:

A

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

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3
Q

Prokaryotes

A

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

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4
Q

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

A

True

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5
Q

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

A

True

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6
Q

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

A

True

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7
Q

What are two very different kinds of prokaryotes?

A

They are classified in the domains Archaea and Bacteria.

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8
Q

Three of the most common prokaryotic cell shapes are:

A
  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.
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9
Q

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

A

True

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10
Q

Prokaryotes can be classified by:

A

shape and by reaction to a Gram stain.

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11
Q

Gram-positive bacteria

A

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

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12
Q

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

A

True

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13
Q

Other features for Prokaryotes:

A

may include a sticky capsule, flagella, or fimbriae.

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14
Q

Prokaryotes (bacteria and archaea)reproduction

A

reproduce by binary fission

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15
Q

The division of on cell reproduce what?

A

reproduces the entire organism

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16
Q

binary fission

A

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

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17
Q

pinches inward, dividing the cell into two

A

Plasma membrane

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18
Q

What forms endospores?

A

Some prokaryotes form endospores that remain dormant through harsh conditions.

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19
Q

What does dormant survival forms of?

A

Forms of bacteria

20
Q

dormant survival form of bacteria resistant to?

A

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

21
Q

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

A

Endospores

22
Q

Anthrax (Bacillus anthractis)

A

common soil bacteria; can be deadly

23
Q

Tetanus (Clostridium tetani)

A

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

24
Q

Botulism (Clostridium botulinum)

A

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

25
Q

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

A

True

26
Q

Two sources of energy can be used by prokaryotes.

A

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

27
Q

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

A

both medical and environmental problems – or benefits.

28
Q

Biofilms

A

– protection from infection
– Hard to eradicate

29
Q

Microbiome

A

– 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

30
Q

Bioremediation

A

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

31
Q

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

A

True

32
Q

• Prokaryotes are:

A

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

33
Q

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

A

True

34
Q

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

A

Bacteria, and later divergence separated the domains Archaea and Eukarya

35
Q

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

A

True

36
Q

Domain Archaea includes

A

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

37
Q

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

A

True

38
Q

VIRUS

A

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

39
Q

Viruses range in size

A

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.

40
Q

Viruses affect bacteria, plants, animals.

A

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

41
Q

True or false, not all viruses cause disease

A

True

42
Q

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

A

True

43
Q

Why the world needs viruses to function

Key to ecosystems

A

• 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

44
Q

Why the world needs viruses to function

Protective to human health

A

• 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

45
Q

Incredibly important in evolution/ exchange of genes

A

• 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.

46
Q

Protists

A

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

47
Q

Protists may be:

A

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