Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

OSU > Micro Final Sec 4 > Flashcards

Micro Final Sec 4 Flashcards

(73 cards)

Start Studying
1
Q

Construct a timeline of life on earth with respect to the appearance of bacteria and eukaryotic cells

A

Earth (4.5 B), Microbial life (~3 B), atmospheric oxygen appears (~2 B), eukaryotic life (~1.9 B)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Identify and describe basic requirements for life on Earth

A

Availability of essential elements (CHONPS)
Continual source of energy (sun)
Temperature range permitting liquid water

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Briefly describe the history of Earth with respect to its approximate age and when oxygen appeared and reached its present level

A

Oxygen appeared around 2.4 byr and reached its present level about 0.6 byr ago

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Describe how DNA sequences can be used a molecular clock

A

It’s assumed mutations occur at a constant rate so when DNA changes significantly, it gives a rough estimate of there being a lineage splitting event

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Define phylogeny

A

The evolutionary history of a group of organisms

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Describe a phylogenetic tree and its purpose

A

Allows you to compare aligned sequences and calculate genetic distance among sequences

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Distinguish between a rooted tree and an unrooted tree based on their definitions and what they look like

A

Rooted: shows position of common ancestor (rectangular)
Unrooted: shows only the relationships of species to one another, no ancestor (circular)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Identify eukaryotic cellular organelles that likely began as endosymbiotic bacteria

A

Mitochondria and chloroplasts

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Identify the 4 well studied bacterial phyla we discussed in class

A

Proteobacteria
Actinobacteria
Firmicutes
Cyanabacteria

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Which phyla is gram negative or gram postive

A

Actinobacteria and Firmicutes are postive
Proteobacteria are negative
Cyanobacteria is kind of like both?

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Rhizobium, Rickettsia, and Caulobacter belong to which genera?

A

alphaproteobacterial genera

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Neisseria belongs to which genera?

A

Beta

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

E. coli and Pseudomonas aeruginosa belongs to which genus?

A

Gamma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Bdellovibrio belongs to which genus?

A

Delta

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Describe the unusual bacteriovorus lifestyle of Bdellovibrio

A

Gets into bacterial cell and eats them from inside out (parasite of other gram negative species)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Helicobacter pylori belongs to which genus?

A

Epsilon

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Key features of phylum Cyanobacteria

A

Oxygenic photoautotrophs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Describe the function of cyanobacterial heterocysts, akinetes, and carboxysosomes

A

Heterocysts: Fix nitrogen
Akinetes: dormant state of a cell (not spores) that withstand extreme conditions
Carboxysomes: place where carbon fixation occurs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Distinguish between Firmicutes and Actinobacteria with respect to the GC content of their DNA

A

Firmicutes have low GC
Actinobacteria have high GC

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Identify 2 genera in Firmicutes

A

Bacillus
Clostridium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What is Clostridium difficile associated with?

A

Hospital acquired diarrhea

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Lactic acid bacteria, Listeria, and Staphyloccocus and Streptococcus are examples of what?

A

Firmicutes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What does “MRSA” mean?

A

Methicillin resistent staphylococcus aureus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Streptomyces is a genus of what?

A

Actinobacteria

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Streptomyces is associated with what?
Clinically useful antibiotics
26
What is Mycobacterium a member of?
Actinobacteria
27
What are two diseases caused by Mycobacteria?
1. Turboculosis 2. Leprosy
28
Describe the unusual cell wall structure of Mycobacteria. What two components do they have that other bacteria do not?
Mycolic acids and phenolic glycolipids –don’t have typical outer membrane
29
Describe the domain Archaea in terms of some archaeal habitats and the occurence of pathogens
No pathogens Live in extreme and normal environments
30
Name four key features of archaea that make them distinct from bacteria
Different lipids Different cell wall structures Different genomic features Different metabolic features
31
Describe how archaeal lipids differ from bacteria lipids
Have ether links Branched fatty acid Extensive branches
32
Describe how archaeal cell walls differ from bacterial cell walls
Don’t have normal peptidoglycan – might have pseudo peptidoglycan Some don’t even have a wall
33
Describe how archaeal genes have similarities and difference from bacteria and eukaryotes
Bacteria: circular chromosomes, similar density/gene size, presence of operons Eukaryotes: presence of Introns and machinery similar to eukaryotes
34
Identify the two major phyla of archaea discussed in class
Crenarchaeota (cren = spring) Euryarchaeota (eury = diverse)
35
Describe features of hot springs and geysers that are important for thermophiles
Reduced minerals, low O2 contenct, steep temperature gradients, acidity
36
Describe how Sulfolobales species can respire in volcanic habitats
Oxidize H2S to generate energy
37
Describe the extreme habitat and metablosim of Pyrodictium species
Live in black smoker (barophiles and hyperthermophiles)
38
What is euryarchaeota associated with?
Methanogens
39
Describe the principal features that define methanogens
Make methane
40
Describe the habitat of members of the class Haloarchaea
Super salty places – Salterns
41
Identify the NaCl concentration typically required by halophilic archaea
1.5 M
42
Propionibacterium is associated with what?
Acne
43
What is Helicobacter pylori associated with?
Stomach ulcers
44
What is dysbiosis?
Imbalance in proportions of different commensal microbes in the gut
45
Describe fecal microbiotal transplants
Isolate healthy bacteria from fecal species and introduce it into a non-healthy species (dysbiosis) to try and restore health (potential way to restore microbiotal populations)
46
Describe how scientists assess the composition of a microbiotal community (what method is most commonly used?)
Extracting the DNA from a sample and subjecting it to 16s rDNA sequencing
47
Distinguish among physical and chemical barriers, innate immune functions, and adaptive immune functions
Physical/Chemical barriers: skin, mucous membranes, stomach Innate Immune functions: use specialized cells to detect and kill microbial invaders that get past the barriers ** Leukocytes (white blood cells), macrophages, cells expressing TLRs Adaptive immune functions: recognizing antigens and epitopes ** Antibodies, cytotoxic T cells
48
Describe the functions of chemical barriers: lysozome, peroxidase, iron binding proteins, and defensins
Lysozyme: degrades peptidogylcan Peroxidase: breaks down hydrogen peroxide into microbe damaging reactive oxygen Iron-binding proteins: bind iron so microbes can’t use it Defensins: small peptides that poke holes in microbial cell membranes
49
Describe pattern recognition receptors (PRRs) in terms of their functions and name two classes of PRRs
Function: recognize PAMPS (signals the presence of foreign invaders or tissue damage) –> cells then sounds alarm Two classes: Toll-like receptors (TLRs) and NOD-like receptors
50
Define cytokine and describe common functions of cytokine
Chemical signals Molecules that immune cells make to signal other cells
51
Describe the complement pathway from C3b to the membrane attack complex (MAC) in terms of what PAMP it senses and which bacteria are susceptible to damage by the MAC
C3b protein of the complement pathway specifically recognizes LPS Membrane attack complex it stimulates is specific for gram negative bacterial cells
52
Distinguish between humoral immunity and cell mediated immunity
Hummoral immunity: involves antibodies (free floating proteins that recognize antigens, which are any foreign chemical structures) **Antibodies bind to antigens –> stimulate other immune responses Cell-mediated: uses T lympthocytes (T cells) that recognize antigens and destroy host cells that are infected
53
Identify T cells and B cells as ___, and they're part of ___
lymphocytes, adaptive immunity
54
Identify primary and secondary lymphoid organs
Primary: bone marrow and thymus Secondary: lymph nodes, tonsils and adenoids, spleen, Peyer’s patches (in small intestine), appendix
55
Define antigen and epitope
Antigen: something that elicits and an adaptive immune response Epitope: the molecular pattern recognized by a given antibody
56
Describe the structure (light chains, heavy chains, variable and constant regions) and major function of antibodies
Heavy and light chains recognize specific molecular patterns Highly variable ends of the antibody fork – antibodies bind to antigens Carboxy termini contains constant region that other immune cells recognize
57
Describe the function of antigen presenting cells
Something that elicits and adaptive immune response **doesn’t necessarily have to be something infective (just has to be foreign) **present antigens to T cells
58
Define the function of the major histocompatibility complex (MHC) with respect to antigen presentation
Antigens are presented on surface proteins called MHC 2.Pieces of foreign invaders are loaded onto MHC proteins for presentation to T cells
59
Describe the function of T cell receptors and what they interact with
Interact with antigens (only see antigens that are presented to them)
60
Distinguish between helper T cells and cytotoxic T cells with respect to their functions
Helper: mediate different immune responses Cytotoxic: kill infected host cells
61
Describe how T cells are "educated" in the Thymus to avoid autoimmunity
They’re educated so that they can effectively recognize antigens from invading pathogens but not react to components of our own
62
Describe the process by which cytotoxic T cells kill infected cells
The activated T(c) cell releases perforin to make holes in the membrane through which granzymes can enter to trigger cell death
63
Describe superantigens and why they can be dangerous
Antigens that can directly connect MCH and TCR molecules, causing massive T cell activation and cytokine release **resulting massive immune response = extensive tissue damage
64
Describe the mechanisms of bacterial exotoxins
LPS released –> results in massive release of cytokines from host cells (sensed by TLRs) Cytokines trigger fever, shock, even death
65
Describe diphtheria toxin and cholera toxin (know the bacterial organisms that make these toxins and their targets in the host)
Diphtheria toxin: targets protein synthesis in the host cell **made by: Corynebacterium diphtheria Cholera toxin: targets second messenger signaling in the host cell **made by Vibrio cholerae
66
Describe bacterial endotoxins in terms of the class of bacteria that make them and where they are located
LPS component of the outer membrane of gram negative bacteria
67
Describe type IV secretion in terms of its mechanism/components and give an example of an organism that uses it
Like a mating pilus – used for conjugation but also modified to secrete proteins (+DNA) Can secrete from either cytoplasm or periplasm Ex: Bordetella pertussis
68
What are targets for antibiotics?
1. Cell wall 2. Cell membrane 3. DNA synthesis 4. RNA synthesis 5. Protein synthesis
69
What is a target for beta lactam antibiotics?
Cell wall
70
What are examples of beta lactam antibiotics?
1. Penicillins 2. Cephalosporins
71
What are mechanisms of antibiotic resistance?
1. Destruction 2. Modification 3. Efflux
72
Is the modification of antibiotic targets a mechanism of antibiotic resistance?
Yes
73
Define persister cells and distinguish persistance from resistance
Persister cell: metabolically dormant, allowing it to survive antibiotic treatment Not genetically encoded Represent a random subpopulation of cells

OSU (17 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions