Ch.8 Microbial Genetics

Question 1

Genetics: the study of —, how they carry —, how information is —, and how genes are —

Answer 1

1. genes
2. Information
3. Expressed
4. Replicated

Question 2

Chromosomes: structures containing — that physically carry — information; the — contain —

Answer 2

1. DNA
2. Hereditary Information
3. Chromosomes contain genes

Question 3

Genes: Segments of — that encode ——, usually —

Answer 3

1. DNA
2. Functional products
3. Proteins

Question 4

Genome: all the —— in a —

Answer 4

1. Genetic Information
2. Cell

Question 5

Genotype:
~ The — makeup of an organism
~ The information that — for all the particular — of the organism
~ ——

Answer 5

1. Genetic
2. Codes, Characteristics
3. Potential Properties

Question 6

Phenotype: — of the genes
~ —, — properties
~ the — of genotype

Answer 6

1. Expression
2. Actual, Expressed
3. Manifestation

Question 7

Regulation of Bacterial Gene Expression:
~ — genes are expressed at a — rate
~ Other genes are expressed as needed
* — genes
* — genes
* — repression

Answer 7

1. Constitutive, Fixed
2. Inductively
3. Repressive
4. Catabolite

Question 8

Pre-transcriptional Control:
~ Repression inhibits —— and decreases ——
* Mediated by —, proteins that block transcription
* Default position of a repressive gene is —

Answer 8

1. Gene Expression, Enzyme Sythesis
2. Repressors
3. On

Question 9

Pre-Transcription Control:
~ Induction turns — gene expression
* Initiated by an —
* Default position for a inducible gene is —

Answer 9

1. On
2. Inducer
3. Off

Question 10

Operon Model of Gene Expression:
~ Promoter: segment of DNA where —— intiates — of structural genes

Answer 10

1. RNA polymerase
2. Transcription

Question 11

Operon Model of Gene Expression:
~ Operator: segment of DNA that —— of structural genes

Answer 11

Controls transcription

Question 12

Operon Model of Gene Expression:
~ Operon: set of — and — sites and the structural genes they —

Answer 12

1. Operator & Promoter
2. Control

Question 13

Operon Model of Gene Expression:
~ In an inducible operon, structural genes are not — unless an — is present
* In the absence of lactose, the — binds to the —, preventing —
* In the presence of lactose, lactose (inducer) binds to the —; the repressor cannot bind to the — and — occurs

Answer 13

1. Transcribed, Inducer
2. Repressor, Operator, Transcription
3. Repressor, Operator, Transcription

Question 14

Operon Model of Gene Expression:
~ In repressible operons, structural genes are — until they are turned —
* Excess — is a — that binds and activated the repressor to bind to the operator, stopping — synthesis

Answer 14

1. Transcribed, Off
2. Tryptophan, Corepressor, Tryptophan

Question 15

Positive Regulation:
~ Catabolite repression: inhibits cells from using — sources other than —

Answer 15

1. carbon
2. Glucose

Question 16

Positive Regualtion:
~ Cyclic AMP (cAMP) builds up in a cell when — is not available
~ cAMP binds to the ——, initiating — and allowing the cell to use —

Answer 16

1. Glucose
2. Lac promoter, Transcription, Lactose

Question 17

Changes in Genetic Material:
~ Mutation: a — change in the —— of DNA
~ Mutations may be —, —, or —

Answer 17

1. Permanent
2. Base Sequence
3. Neutral, Beneficial, or Harmful

Question 18

Mutagens: agents that ——

Answer 18

Cause mutations

Question 19

Spontaneous Mutations: occur in the absence of a —

Answer 19

Mutagen

Question 20

Types of Mutations:
~ ——: change in one base in DNA

Answer 20

Base Substitution (point mutation)

Question 21

Types of Mutations:
~ ——: Base substitution results in change in an amino acid

Answer 21

Missense Mutation

Question 22

Types of Mutations:
~ ——: Base substitution results in a nonsense (stop) codon

Answer 22

Nonsense Mutation

Question 23

Types of Mutations:
~ Frameshift mutation: — or — of one or more — pairs. Shifts the translation “——“

Answer 23

1. Insertion or Deletion
2. Nucleotide
3. Reading Frame

Question 24

Chemical Mutagens:
~ Nitrous Acid: causes — to bind with — instead of —

Answer 24

1. Adenine
2. Cytosine
3. Thymine

Question 25

Chemical Mutagens: ~ Nucleoside Analog: incorporates into — in place of a ——; causes mistakes in ——

Answer 25

1. DNA 2. Normal Base 3. Base Pairing

Question 26

Radiation: ~ Ionizing radiation (X-rays and Gamma Rays) causes the formation of ions that can oxidize — and break the ——— backbone

Answer 26

1. Nucleotides 2. Deoxyribose-phosphate

Question 27

Radiation: ~ UV radiation cause ——

Answer 27

Thymine dimers

Question 28

Radiation: ~ — separate thymine dimers back to the original ——

Answer 28

1. Photolyases 2. Two Thymines

Question 29

Radiation: ~ Nucleotide excision repair: — cut out incorrect — and fill in correct — from other causes as well

Answer 29

1. Enzymes 2. Bases 3. Bases

Question 30

The Frequency of Mutation: ~ Spontaneous mutation rate = 1 in 10^ — replicated base pairs or 1 in 10^ — replicated genes ~ Mutagens increase the mutation rate to per 10 ^ — or 10^ — replicated gene

Answer 30

1. 9 2. 6 3. -5, -3

Question 31

Genetic Transfer and Recombination: ~ Genetic Recombination: exchange of — between —— molecules; creates — diversity

Answer 31

1. Genes 2. Two DNA 3. Gentic

Question 32

Genetic Transfer and Recombination: ~ Crossing Over: —— break and rejoin, resulting in the insertion of —— into the —

Answer 32

1. Two Chromosomes 2. Foreign DNA 3. Chromosome

Question 33

Genetic Transfer and Recombination: ~ Vertical Gene Transfer: transfer of genes from an — to its —

Answer 33

1. Organism 2. Offspring

Question 34

Genetic Transfer and Recombination: ~ Horizontal gene transfer: transfer of genes between — of the ——

Answer 34

1. Cells 2. Same Generation

Question 35

Genetic Exchange in Bacteria: ~ Recombinant: any organisms that contained — that — in another organism

Answer 35

1. Genes 2. Originated

Question 36

Genetic Exchange in Bacteria: ~ DNA transfer between bacterial cells typically involves small pieces of DNA in the form of — or ——

Answer 36

1. Plasmids 2. Chromosomal Fragments

Question 37

Plasmids: ~ Plasmids are ——— pieces of — ~ 1 to 5% the size of a — chromosome ~ Often code for — that enhance the — of a —

Answer 37

1. Self-replicating circular, DNA 2. Bacterial 3. Proteins, Pathogenicity, Bacterium

Question 38

Genetic Exchange in Bacteria: ~ One bacterium donates — to another — is a type of genetic transfer termed —

Answer 38

1. DNA (donor) 2. Bacterium (recipient) 3. Recombination

Question 39

Genetic Exchange in Bacteria: ~ —— gives a portion of its total DNA

Answer 39

Donor Cells

Question 40

Genetic Exchange in Bacteria: ~ —(——) receive the DNA from donor cell

Answer 40

Recipient (competent cells)

Question 41

——— in bacteria involves a portion of the cell’s DNA being transferred from donor to recipient

Answer 41

Horizontal Gene Transfer

Question 42

——— occurs during reproduction when genes are passed from an organism to its offspring

Answer 42

Vertical Gene Transfer

Question 43

Conjugative Plasmid: carries genes for —— and — of the plasmid

Answer 43

1. Sex pili 2. Transfer

Question 44

Dissimilation Plasmids: encode — for the — of — compounds

Answer 44

1. Enzymes 2. Catabolism 3. Unusual

Question 45

Plasmids: ~ Resistance factors (R factors): encode ——

Answer 45

Antibiotic resistance

Question 46

Conjugation in Bacteria: ~ Conjugation: — transferred from one — to another ~ Requires — to — contact via ——

Answer 46

1. Plasmids, Bacterium 2. Cell-to-Cell, Sex pili

Question 47

Conjugation in Bacteria: ~ Donor cells carry the —(——) and are called — cells ~ — cells contain the — factor on the chromosome

Answer 47

1. Plasmid (F factor), F+ 2. HFR, F

Question 48

Transformation in Bacteria: ~Transformation: genes transferred from one — to another as “ —“ —

Answer 48

1. Bacterium 2. “Naked” DNa

Question 49

Transduction in Bacteria: ~ DNA is transferred from a donor cell to a recipient via a —

Answer 49

Bacteriophage

Question 50

Transduction in Bacteria: ~ Generalized transduction: — bacterial DNA is packaged inside a — and transferred to a — cell

Answer 50

1. Random 2. Phage 3. Recipient

Question 51

Transduction in Bacteria: ~ Specialized Transduction: — bacterial genes are packaged inside a — and transferred to a — cell

Answer 51

1. Specific 2. Phage 3. Recipient

Question 52

Transposons ~ Transposons are segment of DNA that can — from one — of — to another ~ ——— that code for transposable that cuts and reseal DNA ~ —Transposons carry other genes (e.g. antibiotic resistance)

Answer 52

1. Move, Region, DNA 2. Contain Insertion Sequences (IS) 3. Complex

Question 53

Genes and Evolution: ~ Mutations and recombination create —— ~ Diversity is the —— for — ~ Natural selection acts on — of organisms to ensure the — of organisms fit for a particular environment

Answer 53

1. Cell Diversity 2. Raw Material, Evolution 3. Populations, Survival