chapter 7

Question 0

compare the # of chromosomes of bacteria with the human cell..

Answer 0

bacteria= 1 chromosome HAPLOID n
human= 46 DIPLOID 2 or more cells

Question 1

what is genome?

Answer 1

sum total of genetic info of a cell(bacteria)

Question 2

what types of nucleic acid make up the genome of bacteria?

Answer 2

..?

Question 3

what can you find in DNA in bacteria? plant and animals DNA?

Answer 3

bacteria= nucleoid

plants & animals= nucleus

Question 4

describe bacterial chromosome: shape, how its packaged inside the cell?

Answer 4

DNA. circular DNA. packaged in loops back and forth.

-chromosome is larger than bacterium

Question 5

what is a nucleioid

Answer 5

bundled DNA

Question 6

describe bacterial plasmids.. shape, size in relation to bacterial cell

Answer 6

circular DNA molecules, 0.1-10% size of chromosome

also smaller than chromosome.

Question 7

function of plasmids:
** not all bacteria have a plasmid

Answer 7

can replicate independently of chromosome, carry genes for resistance. ex: antimicrobial resistance
heavy metal resistance

Question 8

explain R plasmid conjugation

Answer 8

• used for resistance
• bacteria has R plasmid= resistance
• both cells after conjugation become R+

Question 9

describe structure of DNA in bacteria..

Answer 9

one long circular DNA ring—-> replicated in say way with eukaryotic DNA.

Question 10

how many origin of replication are there in bacterial DNA?

Answer 10

1

Question 11

how many replication forks are formed during DNA replication?

Answer 11

only 2 replication forks are used in prokaryotes

Question 12

what is the semi-conservative method of DNA replication?

Answer 12

conserving one original strand of DNA in each new cell..

Question 13

what is gene expression?

Answer 13

process by which DNA directs protein synthesis.

DNA–> RNA—> Proteins

Question 14

what is transcription?

Answer 14

process by which DNA is transferred from one bacterium to another by a virus.

Question 15

what is translation?

Answer 15

process by which nucleotide sequence of mRNA is converted to amino acid sequence of a polypeptide.

RNA—-> Proteins.

Question 16

what part of the cell transcription in prokaryotes is taking place? in eukaryotes?

Answer 16

cytoplasm, nucleus

Question 17

what part of the cell translation in prokaryotes is taking place? in eukaryotes?

Answer 17

cytoplasm, cytoplasm

Question 18

what is gene transfer?

Answer 18

mechanisms for uptake of DNA of create variability .

Question 19

what are two types of gene transfer? describe each.

Answer 19

1. virtical- mother to daughter

2. horizontal- cell to cell (in same generation)

Question 20

what are the 3 processes of gene transfer in bacteria? describe.

Answer 20

1. transformation- uptake of DNA from enviroment
2. transduction- via bacteriophage (lytic, lysogenic cycles)
3. conjegation- direct cell to cell contact

Question 21

describe the process of bacterial transformation..

Answer 21

uptake of ‘naked’ DNA from enviroment.

Question 22

what is a competent cell?

Answer 22

the ability to uptake extracellular ‘naked’ DNA from enviroment.

Question 23

what is transduction?

Answer 23

involves the transfer of DNA from 1 bacterium to another with the use of a bacteriophage.

Question 24

what are the two primary types of bacteriophages? how do they replicate?

Answer 24

1. lytic bacteriophages- replicate by the lytic cycle | 2. temperate bacteriophages- replicate by lysogenic life cycle.

Question 25

describe the lytic cycle..

Answer 25

1. attachment 2. DNA and bacteriophages enter, capsid stays out 3. viral DNA degrades bacterial DNA (degradation) 4. synthesis- making more parts to make more phages 5. assembly- phages are present 6. exit= killing the cell

Question 26

describe lysogenic cycle.

Answer 26

1. attachment 2. entry 3. prophage in chromosome(becomes part of DNA=integration!) 4. replication of chromosomes & cell division 5. inducing agent (antibiotics) 6. synthesis 7. assembly 8. release or exit

Question 27

describe generalized transduction.

Answer 27

1. phage injects its DNA 2. phage enzymes degrade host DNA 3. cell synthesizes new phages that incorporate phage DNA& mistakenly, some host DNA 4. transducing phage injects donor DNA 5. donor DNA is incorporated into recipient chromosome by recombination.

Question 28

what does a transducing phage carry?

Answer 28

bacterial DNA

Question 29

what is bacterial conjugation?

Answer 29

transfer genetic info via direct cell to cell contact, thru sex pilus

Question 30

describe plasmid transfer of F+ conjugation.

Answer 30

1. donor cells attach to a recipient cell with its pilus, then pilus draws cells together 2. cells contact one another 3. one strand of plasmid DNA transfers to recipient 4. the recipient synthesizes a complementary strand to become and F+ cell; the donor synthesizes a complementary strand restoring its complete plasmid

Question 31

discuss chromosomal transfer conjugation of Hfr conjugation..

Answer 31

1. F plasmid integrates into chromosome by recombination 2. cells join via conjugation pilus 3. portion of F plasmid partially moves into recipient cell trailing a strand of donor DNA 4. conjugation ends with pieces of F plasmid & donor DNA in recipient cell; cells synthesize complementary DNA strands 5. Donor DNA & recipient DNA recombine making a F- cell.

Question 32

what are the requirements for 1. transformation 2. transduction and 3. conjugation

Answer 32

1. free DNA in environment and a competent recipient 2. bacteriophage 3. cell to cell and F plasmid

Question 33

what is the state of the donor and recipient cells in 1. transformation, 2. transduction, and 3. conjugation ??

Answer 33

1. dead, living 2. killed by bacteriophage, living 3. living, living