Exam 3 Flashcards Preview

Microbiology > Exam 3 > Flashcards

Flashcards in Exam 3 Deck (48):
1

Functions of DNA

1.) serves as the genetic material responsible for inheritance and is passed from parent to offspring
2.) direct and regulate the construction of the proteins necessary to a cell for growth and reproduction in a particular cellular environment

2

Synthesis of a specific protein with a sequence of amino acids that is encoded in the gene

Gene expression

3

Type of DNA replication where 2 strands of DNA are separate and serve as templates for new complementary strands

Semiconservative

4

Partial unwinding of DNA in the region of RNA synthesis

Transcription bubble

5

Decoding by a ribosome of an mRNA message into a polypeptide project

Translation/protein synthesis

6

Protein function

Functional (enzymes) and structural elements

7

Relationship between an mRNA codon and its corresponding amino acids

Genetic code

8

Molecules and macromolecules that contribute to translation

Ribosomes (rRNA and proteins), mRNA, tRNA, enzymes

9

Prokaryote vs. Eukaryote ribosomes

Pro: 70S in mitochondria and chloroplasts
Eu: 80S in cytoplasm and rER

10

Heritable change in DNA sequence of the organism

Mutation

11

Phenotype most commonly observed in nature

Wild-type

12

Single base replaced by another

Point mutation

13

Shift in reading frame - bases added or deleted

Frameshift mutation

14

Mutation with no effect on protein structure or function

Silent mutation

15

Mutation in which a different amino acid is incorporated resulting in a new polypeptide

Missense mutation

16

Mutation that converts a codon that normally codes for an amino acid codons into a stop codon resulting in a truncated protein

Nonsense mutation

17

What asexual prokaryotes do to achieve diversity

Horizontal gene transfer - transduction, conjugation, transformation

18

Prokaryotes take up naked DNA from environment - comes from other cells that have lysed and released cell contents

Transformation

19

Bacteriophages move short pieces of chromosomal DNA from one bacterium to another

Transduction

20

Bacterial sex in which DNA is directly transferred from one prokaryote to another via a sex pilus, which brings the organisms into contact with one another

Conjugation

21

Most regulation of gene expression occurs through __________ in prokaryotes

Transcriptional control

22

Regulation of gene expression in eukaryotes occurs at _________

Transcriptional level and post-transcriptionally

23

Structural proteins with related functions encoded together in block called ________

Operon

24

Many proteins from one mRNA strand

Polycistionic transcript

25

DNA sequences that influence the operon's own transcription

Regulatory region - promoter, operator, and genes

26

Transcription factor the suppresses transcription by binding to the operator

Repressor

27

Transcription factor that increases transcription by facilitating the binding of RNA polymerase to the operator

Activator

28

Either activates or represses transcription by interacting with a repressor or an activator

Inducer

29

Type of operon that typically contain genes encoding enzymes required for a biosynthetic pathway; example??

Repressible; Trp

30

Type of operon that typically contain genes encoding enzymes in a pathway involved in the metabolism of a specific substrate; enzymes would only be required when that substrate is available; example??

Inducible; Lac

31

Way that is common in eukaryotic gene expression in which eukaryotic transcription can be influenced by binding of proteins to enhancers

DNA looping between enhancer and promoter

32

Chemical modification of DNA molecules or associated histones that influences transcription

Epigenetic regulation; methylation, acetylation, and packaging of DNA

33

The science of using living systems to benefit humankind

Biotechnology

34

Direct alteration of an organism's genetics to achieve desirable traits

Genetic engineering

35

Process that creates new combinations of
genetic material that gets introduced into a new organism

Recombinant DNA technology

36

If the introduced DNA comes from a different species

Transgenic

37

Enzymes that cut DNA into fragments

Restriction (endonucleases) enzymes

38

Enzymes that rejoin DNA together

Ligases

39

Small, circular dsDNA that are commonly used to hold genes that are cut by restriction enzymes

Plasmids

40

Most commonly used mechanism for introducing engineered plasmids into a bacterial cell

Transformation

41

Bacteria that are able to take up foreign DNA

Competent

42

The introduction of recombinant DNA molecules into eukaryotic hosts

Transfection

43

Introduce healthy genes into human patients suffering from diseases that result from genetic mutations

Gene therapy

44

Adenoviruses often used for gene therapy because...

Can be grown to high titer and can infect nondividing and dividing host cells

45

The study and comparison of entire genomes, including the complete set of genes and their nucleotide sequence and organization

Genomics

46

The science of the entire collection of mRNA molecules
produced by cells; compare gene expression patterns between infected and uninfected host cells, gaining
important information about the cellular responses to infectious disease

Transcriptomics

47

Allows scientists to study the entire complement of proteins in an organism; may be used to study which proteins are expressed under various conditions or to compare protein expression patterns between different organisms

Proteomics

48

Types of molecular analysis of DNA

DNA probes, DNA/protein gel electrophoresis, restriction fragment length polymorphism (RFLP) analysis, southern/northern blots, microarray analysis, and DNA sequencing