MB C8 Self Quiz

tokia's version from 2016-04-29 04:04


Question Answer
1. What are the main characteristics of gene transferGene transfer is the movement of genetic information between organisms. In most eukaryotes it is an essential part of the organism's life cycle and usually occurs by sexual reproduction.When genes pass from parents to offspring it is called vertical gene transfer.Sexual reproduction is usually what we think of as vertical gene transfer.However in bacteria vertical gene transfer takes place asexually by binary fission.Bacteria also do horizontal or lateral gene transfer when they pass genes to other microbes of their same generation.Bacteria have three main mechanisms of lateral gene transfer: transformation...transduction adn conjugation.Gene transfer is significant because it increases the genetic diversity of organisms which increases the likelihood that some will adapt to changing environmental conditions and not die out.This diversity leads to evolutionary changes.


Question Answer
2. Uptake of naked DNATransformation
Virus involvedTransduction
Competence factorTransformation
F piusConjugation
3. (t/f)Temperate phages can carry out both specialized transduction where any bacterial gene can be transferred and generalized transduction where only specific genes are transferredFalse
4. In the lysogenic cycle of bacteriophages which of the following is trueLysogeny is the term applied to a temperate phage that does not replicate itself independently and does not lyse the bacterial host cell...Phage DNA is incorporated into the host bacterium's DNA upon which time it is called a prophage...Temperate phages can be replicated either as a prophage along with bacterial chromosomal replication or can suddenly revert to the lytic cycle by replicating themselves and assembling into new phages
5. Which of the following is not true about conjugationThe number of genes transferred depends only on whether the donor cell is F+ or F-


Question Answer
6. What are the three mechanics of conjugation and how do they differThe three mechanisms of conjugation are F plasmid transfer..Hfr and F'.In F plasmid transfer a whole extrachromosomal piece of DNA (plasmid) is transferred from F+ sex pilus bearing donor cells to F- recipient cells.The recipient cell now becomes F+.In the high-frequency recombination (Hfr) mechanism only parts of F plasmids that have been incorporated into the bacterial chromosome (initiating segment) are transferred along with adjacent bacterial genes.The recipient cell does not become F+ as only part of the F plasmid is transferred.In the F' mechanism an F plasmid incorporated into the chromosome and bearing one or more bacterial genes from the previous donor subsequently separates from the chromosome and is completely transferred along with a fragment of the new chromosome (and bearing one or more genes) to the recipient F- cells.Such a transferred plasmid is known as a F' plasmid.
7. When the F plasmid is incrporated into the choromosome of F+ bacteria these cells are calledHigh-frequency recombinants


Question Answer
8. Which of the following would inhibit transformationFalse
9. Contributes to genetic diversitytransformation...transduction...conjuction
Provides a means of mapping genes in bacterial chromosomesconjugation
Suggests a mechanisms for viral origins of cancertransduction
May represent an evolutionary stage between asexual and sexual reproductionconjugation
Can be used to create recombinant DNAtransformation
Demonstrates a close revolutionary relationship between prophage and host cell DNAtransduction
10. Which of the folowing is characteristic of a plasmidPlasmids can carry genes for antibiotic resistance and bacteriocins that inhibit growth of other competing bacteria...Some plasmids can carry genes for catabolic enzymes and virulence factors...A plasmid is a circular double-stranded extrachromosomal piece of DNA that is self-replicating


Question Answer
11. A genetic sequence that can move from one location to another within a cell is known as aTransposon
12. Recombinant DNA isDNA that is produced when genes from one kind of organism are introduced by lateral transfer into the genome of another kind of organism
13. A bacterium can acquire the ability to make a new enzyme or toxin naturally by Transformation...Conjugation
14. A bacterium that has had its cell wall removed is calledA protoplast


Question Answer
15. Gene amplificationThe addition of plasmids to microorganisms inorder to increae the yield of useful gene products
Genetic engineeringManipulation of genetic material to alter an organism's characteristics
Protoplast fusionCombines organisms without cell walls allowing them to mix their genetic information
Restriction endonucleasesEnxymes that recognize specific sequences of 4 to 8 pairs of DNA where it then cuts across to create a restriction fragment
Genetic fusionAllows the transposition and joining of genes from two separate genes that were originally located at different position on the chromosome
TransgenicResults when the new DNA is produced by taking genes from one kind of organism and introducing them into the genome of another different organism


Question Answer
16. In the laboratory cells can be rendered _____ by the use of cold calcium chloride or electroporationCompetent
17. Biotechnology and genetic engineering or molecular genetics can be used to make all of the following exceptLife
18. (t/f)Formation of frost on agricultural plants is in part due to microorganismsTrue
19. Hybridomas are formed by fusing antibody-producing white blood cells withMyeloma cells
20. Individual hybridoma cells produce only one type or _____ antibodiesMonoclonal


Question Answer
21. Phages that destroy host cell DNA direct synthesis of phage particles and cause lysis of the host cell areVirulent phages
22. Which of the folowing statements concerning recombinant DNA technology is falseRecombinant DNA technology provides a high degree of risk to the health of the general population
23. The first vaccine for human use produces using recombinant DNA technology was thePolio vaccine
24. Which of the following is not a method by which bacteria naturally alter or exchange their genetic informationProtoplast fusion
25. Identify processes (a) through (e) in the following diagram(a)Lytic cycle (b)Lysogenic cycle (c)Empty phage heads and pieces of phage DNA are assembeld (d)Phage is replicated along with bacterial DNA (e)Phage is absorbed to receptor site on bacterial ell wall penetrates it and inserts DNA