1
Q
List some examples of ubiquity
A
microbes are everywhere
2
Q
Positive contributions
A
significant portion of all food webs and important in the nutrient cycle as producers and decomposer genetic and metabolic reactions vaccines probiotic genetic engineering
3
Q
Define taxonomy
A
4
Q
What are the eight major taxonomic levels in order
A
Domain, Kingdom, Phylum, Class, Order, Family, Genus, and Species (strain)
5
Q
Define auto and hetero
A
autotroph (producer) synthesizes its own organic compounds from inorganic sources, such as carbon dioxide and light or chemical energy. heterotroph (consumer/decomposer) obtains its energy from pre-formed organic matter
6
Q
Describe major categories of microbes
A
bacteria, archaea, fungi, protozoa, algae, and viruses. Bacteria and archaea are single-celled prokaryotes, while fungi, protozoa, and algae are eukaryotes that can be unicellular or multicellular. Viruses are acellular infectious particles that depend on a host cell for replication
7
Q
What are the components of cell theory?
A
made of one or more cells
the cell is the fundamental unit of life
come from preexisting cells
have the same basic chemical composition
use energy
contain DNA
8
Q
Cell arrangement (3)?
A
unicellular / colonial that have mult cells but can survive as inds / multicellular have many cells and depend on each other
9
Q
Common features all cells have (4)?
A
all cells have a plasma / cytoplasm / ribosomes / DNA
10
Q
PRO = ?
A
tiny/ no nucleus / no organelles / bacteria or archaea
11
Q
EUK = ?
A
large / DNA in nucleus / organelles / protists or plants or fungi or animals
12
Q
Draw a bacterial cell
A
does it have? Plasma membrane cell wall capsule flagellum pilus fimbriae cytoplasm ribosome nucleoid plasmid inclusions
13
Q
What is morphology?
A
physical appearance of bacterium including gram stain (+/-) acid fast stain cell arrangement and shape
14
Q
A bacteriums cell shape is determined by…?
A
the cytoskeletal structure
15
Q
A round bacterial cell shape is called a ?
A
Coccus/cocci
16
Q
A short rod bacterial cell shape is called a ?
A
coccobacillus
17
Q
A long rod bacterial cell shape is called a ?
A
Bacillus/bacilli
18
Q
A curved rod bacterial cell shape is called a ?
A
Vibrio
19
Q
A wavy bacterial cell shape is called a ?
A
Spirillum/spirilla
20
Q
A corkscrew bacterial cell shape is called a ?
A
Spirochete
21
Q
Bacterial cell arrangement is determined by?
A
the plane of cell decision (non-motile stick together and motile cells separate)
22
Q
The arrangement of round bacterial cells in a pair is called…
A
Diplococci
23
Q
The arrangement of round bacterial cells in a chain is called…
A
Streotococci
24
Q
The arrangement of round bacterial cells in a cluster is called…
A
Staphylococci
25
The arrangement of rod bacterial cells in a pair is called…
Diplobacilli
26
The arrangement of rod bacterial cells in a chain is called…
Streptobacilli
27
Nucleoid
region in cell where chromosomes are located no nuc since prokaryotic
28
Chromosome
Dna contains genes for normal cll function and most bacteria have only one circular chromosome (haploid)
29
Plasmids
Extrachromosomal DNA with genes for advantages but not needed for survival
30
Ribosome
catalyze translation stage of protein synthesis
31
Inclusions
storage of synthesized macromolecules similar to vesicles but w/o phospholipid membrane
32
Gas vesicles
provides buoyancy to cell very common in cyanobacteria
33
Fimbriae
cell wall extensions for attachment to hoast cell surfaces
34
Sex pilus
tubular structure for DNA transfer (SEX)
35
Flagella
long appendages for motility
36
Capsule
thick external polysaccharide layer that camouflages bacteria and interferes with phagocyte binding
37
Slime layer
thin external polysaccharide layer
38
Endospores
dormant cell stage resistant to harsh environment
39
What is the bacterial cell wall?
semi-rigid external structure preventing cell lysis in hypotonic solutions (in bacteria there are two types: gram +/ -) and determines where microbe thrives and what antibiotics are used
40
What is peptidoglycan?
major component of cell wall that allows for flexibility but provides structure (this is what differentiates gram + -) / composed of parallel glycan chains and cross linked by peptide chains / foreign to EUKs and can trigger immune response / digested by enzyme lysosome / synthesis inhibited by certain antibiotics
41
Gram + cell wall
THICK peptidoglycan external (acids anchor peptidos to cell membrane)
42
Gram -
thin Peptidoglycan with external outer membrane composed of LPS (lipopolysaccharides - endotoxin only found in EUKs) and phospholipids that stabalize cell wall
43
Bacterial reproduction
most replicate through binary fission (asexual that produced genetically identical daughter cells) or via conjugation (sexual that increases variation)
44
How do bacteria sense and respond?
receptors are sensitive to a specific stimulus and effectors provide response capability / important because of competition for environment
45
Explain example of basic sensory mechanism
receptor protein in cytoplasmic membrane activated when stimulus is present and phosphorylates region internally that is then transferred to response regulator turning genes on or off to trigger cytoplasmic changes
46
What is quorum sensing?
ability for cells to coordinate activity through communication allowing for regulation and decision roles in high density settings resulting in cells that have roles to divide labor
47
How does quorum sensing work?
at LOW population density cells function INDIVIDUALLY / at HIGh pop density cells function as GROUP
48
What are the steps to quorum sensing?
1. Bacterial cells produce small signal molecules (no response at low concentration) 2. Signal molecules accumulate as cell numbers increase 3. When cell number reaches a certain density signal threshold is met and signal molecules bind to receptors 4. Group regulates and triggers specific behavior
49
Why is bacterial cell motility important?
get to nutrients or away from danger
50
What is Taxis?
movement response (chemo = chemical photo = light aero = O2 ) (positive = to attractant or negative = away from repellant)
51
If a bacteria is moving to a chemical it is…
positive chemotaxis
52
How to bacteria move?
flagella with tumbles (spinning clockwise flagellar rotation) and runs ( counterclockwise flagellar motion)
53
Difference in mobility in concentration or no concentration
no concentration is random tumbles and runs as bacteria searches for food or danger / in gradient cell tumbles less and runs more to get to or away from something
54
Fill-in-the-blank: A ___________ is a thick external polysaccharide layer found in some bacteria
capsule
55
What are the restrictions for gene transfers?
taxonomy must be similar
56
What is biotechnology
use of living systems (usually bacteria) and organisms to make proteins Explain “cats don't mate with dogs”
57
Why is recombination random?
trait may or may not be received by recipient (you cant control what you get)
58
What does current biotech allow us to do?
no taxonomic relationship is required and donors can be from different domains (bacteria can receive human genes) / recombination is specific and changes can be made in 1 generation
59
Restriction enzyme
cut dna into small fragments (each enzyme will ALWAYS cut at the same site regardless of source)
60
DNA ligase
enzyme joins DNA fragments having complementary end sequences (AT & CG) / can join DNA fragments cit with same restriction enzyme from any organism (can splice human and bacterial DNA)
61
Gel electrophoresis
separates DNA fragments based on their size (number of nucleotides) with electrical current drawing neg DNA to positive electrode and smaller fragments move easier producing DNA bands which can be cut from gel
62
DNA fingerprinting
uses gel from electrophoresis to make DNA profile that can be used for genetic analysis
63
DNA sequencing
identified specific type and order of nitrogen bases in genome / gene identification and comparison that can be used for making synthetic DNA
64
PCR polymerase chain reaction
used to make multiple copies of DNA from small sample that can be used for analysis cloning sequencing forensics and genetic screening (after 5 min you can make 1 copy into 32)
65
Nucleic acid probes
DNA or RNA fragments of a known sequence with radioactive color label attached / probe only attach to complimentary sequence thus identifying them making it useful for disease diagnosis and genetic sequencing
66
CRISPR
used to insert or silence specific genes / natural bacterial immune system that can be used for gene therapy
67
What is genetic engineering?
horizontal gene transfer applied through technology where the recipient gains ability to produce new proteins encoded by donor DNA / taxonomy DOESN'T matter / new engineered cells pass on engineered into new generations
68
IDENTIFY genetic engineering protocol (EX: human insulin production)
1. DNA isolated from donor cells and cut with restriction enzymes then separated by gel electrophoresis 2. Gene of interest identified cis nucleic acid probes cut from gel 2. DNA fragments amplified by electrophoresis (PCR) 4. Plasmid DNA isolated from bacterial cells used as a vector to transmit gene 5. Plasmid DNA cut with the same restriction enzyme used for donor 5b. DNA ligase used to splice donor DNA into bacterial plasmid 6. Recombinant plasmids enter bacterial cells 7. Transformed bacteria replicate increasing numbers 8. Transformed bacteria express donor genes 9. Protein is harvested
69
What are GMOS (genetically modified organisms)?
organisms with altered DNA/RNA which would not naturally occur (also called transgenic organisms) EX: chickens with huge breasts
70
Example of GMO for cows
cow engineered with human gene for milk proteins that benefits people with allergy to milk proteins in natural cow
71
Example GMO for PIGS
fertilized pig egg is injected with human cell to inhibit pancreas formation so that it will grow a human pancreas used for transplant or to produce hemoglobin
72
What is golden rice?
rice that has been engineered to produce large amounts of Vitamin A used for making visual pigments which can treat night blindness
73
Example “Bt corn”
engineered to produce its own insecticide against corn-eating insects that is harnessed to humans and negates need for pesticide sprays in fields and can save pollution to water supplies
74
Example transgenic kitten
immune to FIV and includes gene for fluorescence allowing for confirmation (if your cat glows in the dark its safe)
75
Ethical implications in GMO’s as food
overpopulation (not enough resources for hunger)
76
What is gene therapy?
attempt to treat genetic abnormalities via introduction of functional gene in a vector virus (reduces symptoms but leaves possibility to pass disease onto offspring)
77
Steps to gene therapy with vector virus
1. Cells harvested from patient 2. Virus altered so it cant reproduce 3. Egen inserted into virus 4. Altered virus mizes with patient cells 5. Cells become transgenic 6. Altered cells injected into patient body 7. Altered cells produce disered protein
78
How is CRISPR used?
gene insertion (target spliced into genome but faulty gene remains) or gene slicing (faulty gene disrupted and removed)
79
How is gene therapy currently used?
somatic (non-reproductive) cells / calls for moratoriums on germ-line therapy that have mixed results (not allowed in US)
80
What are bioethics?
consideration of ethical issues (ecological impact
81
Exam next thursday
82
What are the six components of the cell theory?
1. All living things are composed of cells. 2. The cell is the basic unit of life. 3. All cells come from pre-existing cells. 4. Cells contain hereditary information. 5. All cells have a plasma membrane. 6. All cells have cytoplasm.
83
Define unicellular organisms.
Organisms made up of only one cell.
84
What are colonial organisms?
Organisms that have multiple cells, but the cells can survive as individuals.
85
What characterizes multicellular organisms?
Organisms that have multiple cells which depend on each other.
86
List the common features of all cells.
* Cell membrane * DNA * Cytoplasm * Ribosome
87
What are prokaryotic cells?
Extremely small cells that lack a nucleus and organelles.
88
What are eukaryotic cells?
Larger cells that contain DNA in a nucleus and several organelles.
89
What is bacterial cell morphology?
The physical appearance of a bacterium, typically described by shape, arrangement, and staining characteristics.
90
What is the significance of cell shape in bacteria?
Cell shape is determined by the cytoskeletal structure and is easier to observe with young cultures.
91
What are the two primary types of bacterial cell walls?
Gram-positive and Gram-negative.
92
What is the function of the bacterial cell wall?
Prevents cell lysis in hypotonic situations.
93
What is peptidoglycan?
A major component of the cell wall that imparts rigidity and flexibility.
94
How does Gram-positive cell wall differ from Gram-negative?
Gram-positive has a thick peptidoglycan layer, while Gram-negative has a thin peptidoglycan layer with an outer membrane.
95
What is the role of ribosomes in bacterial cells?
Catalyze the translation stage of protein synthesis.
96
What are plasmids?
Extrachromosomal DNA that provides advantages in specific situations, such as antibiotic resistance.
97
What is binary fission?
Asexual reproduction in bacteria that produces genetically identical daughter cells.
98
What is conjugation in bacteria?
A form of sexual reproduction that increases genetic variation in a population.
99
Define chemotaxis.
Movement in response to a chemical stimulus.
100
What is quorum sensing?
A communication process that allows bacterial cells to coordinate activities and divide labor in high-density settings.
101
Fill in the blank: The _______ is a region in the cell where the chromosome is located.
nucleoid
102
True or False: Bacterial cells can sense and respond to their environment individually.
True
103
What is the function of flagella in bacteria?
Long extracellular appendages used for cell motility.
104
What do gas vesicles provide to bacterial cells?
Buoyancy.
105
What triggers the immune response in Gram-negative bacteria?
Lipopolysaccharide (LPS).
106
What type of movement do bacteria use to search for food?
A series of tumbles and runs.
107
What is the role of fimbriae in bacterial cells?
Cell wall extensions for attachment to host cell surfaces.
108
What is the role of the capsule in bacteria?
Interferes with phagocyte binding and may camouflage the bacterium.
109
Fill in the blank: Bacterial cells use _______ for motility.
flagella
110
What is the structure of a Gram-positive bacterial cell wall?
Thick peptidoglycan layer external to the cytoplasmic membrane.
111
What is the main characteristic of endospores?
They are dormant cell stages resistant to harsh environmental conditions.
112
113
What encodes genetic information in all organisms?
DNA
## Footnote
DNA provides the instructions for all structure and function of the organism.
114
What are the monomers that make up DNA?
Nucleotide monomers
## Footnote
The sequence of nitrogen bases in the nucleotides determines genetic content.
115
What are genes?
Units of genetic information
## Footnote
Some genes are instructions for synthesizing proteins; others are for regulation of gene function.
116
In bacteria, how many proteins does one gene typically code for?
One protein
117
In eukaryotes, how many proteins can one gene code for?
Multiple proteins
118
What are the two types of sequences found in eukaryotic genes?
Exons and introns
119
What is an operon?
A group of genes controlled by a common promoter and transcribed together into mRNA
120
What is the role of RNA polymerase?
Identifies gene location, produces mRNA, determines amino acid sequence
121
What does the term 'upstream' indicate?
Any sequence that precedes
122
What does the term 'downstream' indicate?
Any sequence that follows
123
What is the genetic code based on?
Which amino acid is indicated by a specific codon
124
What is the flow of genetic information?
DNA -> mRNA -> Polypeptide
125
What is gene regulation?
Activation or inactivation of genes based on various conditions
126
What is repression in gene regulation?
Inactivation of genes that are normally active
127
What is induction in gene regulation?
Activation of genes that are normally inactive
128
What is a point mutation?
A substitution of a base that may or may not affect the coded protein
129
What is a frameshift mutation?
Insertion or deletion of a base that affects all codons following the mutation
130
What can increase the rate of mutation?
Mutagens such as radiation and chemicals
131
What happens if a mutation does not change the amino acid sequence?
The mutation will have little or no effect on the organism
132
What happens if a mutation changes the amino acid sequence in a critical location?
It may lead to natural selection
133
What is vertical gene transfer?
A mother cell passes its genes to its offspring through normal cell division
134
What is horizontal gene transfer?
A donor cell passes genes to other bacteria
135
What occurs during transformation?
Bacteria take up DNA fragments from their surroundings
136
What is transduction?
A virus transmits DNA from one bacterium to another
137
What occurs during conjugation?
A donor bacterium passes DNA to another bacterium via a sex pilus
138
What is the common mechanism for the spread of antibiotic resistance?
Transformation
139
What is the significance of the genetic code being universal?
All organisms use the same code, making gene transfers possible
140
What are prions?
Mutant mis-folded forms of a normal brain protein (PrP) required for normal brain function.
141
How are prions most commonly transmitted?
By consuming an infected animal.
142
What is the effect of the prion (PrPSC) on normal brain proteins (PRPC)?
PrPSC causes PRPC to fold into the mutant form, amplifying their number.
143
What happens to the brain tissue as prions accumulate?
Disruption of function and causing neuron death.
144
What are the steps in the prion infection process?
1. Spontaneous mutation or consumption of PrPSC
2. PrPSC interacts with PrPC
3. PrPSC converts PRPC to PrPSC
4. PrPSC accumulates in brain tissue.
145
What is the result of the accumulation of mutant proteins in the brain?
They stick together to form plaques in the cerebral cortex.
146
What is the consequence of neuron function disruption due to prions?
Neurons die and holes form in the cerebral cortex, causing brain shrinkage.
147
What are prion diseases collectively called?
Spongiform encephalopathies.
148
Is there a cure for prion diseases?
There is no cure.
149
Identify the prion disease associated with sheep and goats.
Scrapie.
150
Identify the prion disease associated with cows.
Mad cow disease (BSE).
151
Identify the prion disease associated with deer and elk.
Chronic wasting disease.
152
Identify the prion disease associated with humans due to ritual cannibalism.
Kuru.
153
What is Creutzfeldt-Jakob Disease (CJD) associated with?
Spontaneous or inherited mutation in humans.
154
What is variant CJD (vCJD) associated with?
Eating contaminated meat from cows, sheep, goats, deer, or elk.
155
What are viruses classified as?
Acellular infectious particles
156
Do viruses meet the minimum requirements for life?
No
157
What do viruses lack that is essential for life?
Ribosomes, cytoplasm, or cell membrane
158
What type of pathogens are most viruses?
Obligate intracellular pathogens
159
Why do viruses need to be inside host cells?
To replicate and carry out metabolism
160
What is the size range of viruses?
Measured in nanometers (nm)
161
What is required to visualize most viruses?
Electron microscopes
162
How are viruses first classified?
By the type of host cells they infect
163
What are eukaryotic viruses further classified by?
The kingdom of host cells they infect
164
What do bacteriophages infect?
Prokaryotic cells
165
What type of cells do eukaryotic viruses infect?
Eukaryotic cells
166
What are the four criteria used for viral classification?
* Taxonomic family of virus
* Disease the virus causes
* Type of nucleic acid
* Route of transmission
167
What is the basic core structure of all viruses?
Nucleic acid and a protein capsid
168
What types of nucleic acids may viruses have?
* DNA
* RNA
169
What is the function of the protein capsid in viruses?
Protects the genetic material
170
What are the two classifications of viruses based on their structure?
* Naked viruses
* Enveloped viruses
171
What defines a naked virus?
Does not have a membrane surrounding the capsid
172
What defines an enveloped virus?
Has a membrane surrounding the capsid
173
What is host range and specificity in viruses?
Refers to the type of hosts and host cells which can be infected by a given virus
174
What primarily determines the host range and specificity of a virus?
Host cell receptors and membrane receptor proteins
175
True or False: Viral spikes or tail fibers must match the shape of the host cell receptor.
True
176
What are the two main pathways of viral replication?
* Lytic cycle
* Lysogenic cycle
177
What happens during the lytic cycle of viral replication?
Infect, replicate, and spread
178
What occurs in the lysogenic cycle?
Viral genome inserts into the host genome and may remain silent
179
What type of virus is HIV classified as?
Retrovirus
180
How does HIV's replication cycle differ from typical lysogenic viruses?
It does not remain silent and produces new viral particles
181
What type of infections are typically associated with lytic viruses?
Acute infections
182
What type of infections are typically associated with lysogenic viruses?
Latent infections and some cancers
bio 150
flashcards
Decks in class (6)
# Cards
