Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Micro Test 2- Albertson > Microbial Genetics > Flashcards

Microbial Genetics Flashcards

1
Q

The entire complement of genes on all chromosomes normally found in an organism; hereditary information

A

Genome

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

The entire double-strand of DNA containing multiple genes (nuclear material or nucleic acid)

A

Chromosome

The chromosome is always DNA, except RNA viruses

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

A segment of DNA that contains the genetic code (blueprint) for a functional product

A

Gene

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

Genetic code is translated into proteins for…

A

Structural, catalytic or regulatory function within the cell with aid of messenger RNA and ribosome

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

Genetic code for each protein is carried as a ____________ in the nucleus acid macromolecule

A

Sequence of nucleotide molecules

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

The total genetic make up of an organism (potential properties of the cell)

A

Genotype

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

Actual, expressed properties of an organism

A

Phenotype

Almost all of a cells properties drive from the structural and function of its proteins

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

Nucleotide composition (3’ 5’)

A

Always added to exposed 3’ end of the growing strand

- thus the strand grows in the 5’ to 3’

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

A nucleotide consists of?

A

5-carbon sugar- ribose or deoxyribose

Phosphate group - bound to 5’ of sugar molecule

Nitrogenous base - could to the first or 1’ carbon of 5-carbon sugar

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

In a nucleotide what can the nitrogenous base be composed of?

A

Purine

  • Adenine
  • Guanine

Pyrimidine

  • Thymine
  • Cytosine
  • Uracil - only in RNA
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is involved in nucleotide pairing?

A

Adenine to Thymine (or Uracil)
(2 hydrogen bonds)

Guanine to Cytosine
(3 hydrogen bonds)

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

DNA stands are and what does this mean?

A

Antiparallel

Two stands run in opposite directions
Nucleotide of 3’ end pairs with the nucleotide of 5’ end of the other stands

Stands are not identical, but are complementary

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

What does DNA consist of?

A

A double helix of paired nucleotides (A to T and G to C) attached to the deoxyribose

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

What is the direction of the strand in DNA?

A

The end with no phosphate bound to 3’ carbon of the sugar is called the 3’ end

The end with the phosphate is bound only to the 5’ carbon is called the 5’ end

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

How is the replication fork formed?

A

Where short lengths of double- stranded DNA helix UNWIND, thus exposing separate strands

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

What is the unwinding due to in replication forks?

A

The action of enzymes such a helical and DNA gyrase which break the hydrogen bonds between bases

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

What does DNA polymerase do to DNA?

A

Binds DNA and inserts complementary nucleotides thereby generating a new stand

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

What does DNA polymerase also do?

A

Edits for errors with accuracy of about 1 error in a billion base pairs replicated

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

What is the leading strand of DNA?

A

Newly grown strand having the 3’ end of the exposed nucleotide “facing forward” leading the replication fork

  • New strand grows towards
  • Strand is continuously replicated because of enzymatic simplicity and ease of access to molecule
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What is the lagging strand of DNA?

A

The strand having the 5’ end exposed nucleotide facing forward the replication fork

  • Strand grows away from the replication fork, accomplished by replicating short fragments, then connecting them together to form new complement strand
  • RNA primer and RNA polymerase needed to initiate strand growth in the absence of a nucleotide having a 3’ binding site
  • DNA polymerase takes over replication and continues within one nucleotide of the existing, previous generated strand. DNA polymerase cant join fragment to existing strand because cannot facilitate linking both 3’ to 5’ binding sites
  • DNA Ligase facilitates linkage of both 3’ and 5’ binding simultaneously, inserts nucleotide to join new replicated fragment with existing strand
  • This replication is discontinuous
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

The new double-strand DNA will do what while the parental DNA does what?

A

The new DNA re-winds

The parental DNA unwinds exposing more nucleotides to be replicated

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

Large, single strand molecules of nucleotides

A

RNA

- U replaces T

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

Carries the genetic code from the DNA to the ribosome

A

Messenger RNA (mRNA)

Ribosome is the site of protein synthesis

24
Q

Three nucleotides on the mRNA that specify the amino acid to be placed in a polypeptide

A

Codon

3 nucleotides = 1 codon

1 codon = 1 amino acid

25
Q

Transports and then transfers the amino acid to the developing peptide chain

A

Transfer RNA (tRNA)

26
Q

The site on the tRNA that bonds w/ the codon on the mRNA and what does this do?

A

Anticodon

  • carries the three bases which complement the codon
  • specifies which amino acid will be carried bu the tRNA
27
Q

Assists protein synthesis by serving as a facilitator for the mRNA and tRNA functions

A

Ribosomal RNA (rRNA)

28
Q

The transfer of the genetic code on DNA gene into a messenger RNA (mRNA) strand by means of DNA- dependent RNA polymerase

A

Transcription

29
Q

What are the steps of transcription?

A
  1. DNA double helix unwinds a portion and strands separate exposing nucleotides
  2. RNA polymerase binds to the DNA at promoter site (beginning of gene)
  3. Complementary RNA nucleotides are joined together in sequence by the RNA polymerase
  4. Transcription ends when RNA polymerase reaches the termination region of the gene, and new single-stranded mRNA is released (the DNA re-winds)
30
Q

The synthesis of a polypeptide at the ribosome through linkage of amino acids in a sequence specified by a mRNA molecule

A

Translation

31
Q

What are the steps of translation?

A
  1. mRNA attaches to the ribosome with the “start” codon in place
  2. A tRNA with the complementary anticodon matches to the codon on the mRNA, thus brining the first amino acid into place
  3. As the mRNA codons are matched with complementary tRNA anticodons, the amino acids are linked together and the tRNA released
  4. Polypeptide chain is released when the reading frame reaches the “stop” codon
32
Q

What are constitutive genes?

A 
Constantly expressed 
(transcribed and translated into functional products)

(60-80% of genes are in this category)

33
Q

Can be “turned on”

A

Inducible genes

34
Q

Can be “turned off”

A

Repressible genes

35
Q

Related genes that are regulated as a group/ series

A

Operon

- genes which code for the enzymes of a single metabolic pathway

36
Q

An operon has what?

A

Repressor gene
Promoter site
Operator site
Genes of the operon

37
Q

Codes for a “repressor” protein which can bind to the “operator” region

A

Repressor gene

38
Q

Region of the chromosome to which the RNA polymerase binds during transcription

A

Promoter site

39
Q

Region of the chromosome which controls (either permits or blocks) access of the RNA polymerase to the structural genes of the operon; site to which the repressor protein binds (or fails to bind)

A

Operator site

40
Q

Adjacent genes of the operon which direct the synthesis of proteins with related functions and which are regulated as a unit

A

Genes of the Operon

41
Q

What is an inducible operon?

A

Genes expressed only when certain environmental conditions are present

  • Presence of substrate causes operator site to be unblocked
42
Q

What is a repressible operon?

A

Genes expressed EXCEPT when certain environmental conditions are present

  • presence of metabolic products causes operator site to be blocked
43
Q

Changes (substitution of deletions) in the sequence of DNA bases, thus changing the genetic code

A

Mutation

44
Q

What are the three types of mutations?

A

Base substitution
Frameshift mutation
Gross mutation

45
Q

A single base is replaced with another, thus changing the codon.

A

Base substitution

  • may result in an improper amino acid in the protein (not highly significant)
46
Q

Insertion or deletion of bases may shift the codon reading frame of the mRNA in ribosome

A

Frameshift mutation

  • often results in significantly different or non functional protein
47
Q

Gain or loss of entire gene segment or inversions or transposition of gene sequences

A

Gross mutations

  • results in major change or non-functional cell
48
Q

What are these mutations caused by?’

A

Spontaneous mutation
- occurs about once in a million replicated genes

Chemical mutagens
- nitrous acid, base analogs (do not pair properly)

Radiation
- X-ray, gamma rays, uv light

49
Q

Small, circular, self-replication piece of DNA in bacteria

A

Plasmid

50
Q

Characteristics of plasmid

A
  • Separate from the normal chromosomal DNA
  • Genes usually not essential for growth of bacterium
  • Genes often code for antibiotic resistance or disease- causing factors
  • Can be used in the genetic engineering process (hepta-vax)
51
Q

Integration of the DNA of a temperate bacteriophage (virus) into the bacterial chromosome where it replicates along with the bacterial chromosome

A

Lysogeny

52
Q

The transfer of genetic material between donor and recipient cells involving direct cell-to-cell contact

A

Conjugation

53
Q

Characteristics of conjugation

A
  • Sex pills (hollow tube extending from one bacterium to another) is used to transfer DNA from one cell to another
  • A copy of DNA strand or plasmid is transferred to the recipient cell
54
Q

The direct transfer of genes from one bacterium to another as “naked” DNA in solution

A

Transformation

  • Free DNA from one cell is incorporated into the DNA of another; usually follows cell breakdown and release of DNA after bacterial death
55
Q

The transfer of DNA from donor bacterium to recipient bacterium by using a bacterial virus as a the vehicle

A

Transduction

  • Host DNA or plasmid is accidentally enclosed in a bacterial virus during exit of the virus from the bacterium

Micro Test 2- Albertson (3 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions