Chapter 08 - Bacterial Genetics and Biotechnology

Question 1

Genomes

Answer 1

Contains the genetic material (genes) necessary to produce a functional molecule, usually a polypeptide, i.e., gives the organism its traits
Includes all types of DNA found in a cell, which includes all types of DNA found in the cell

Question 2

Do all cells have chromosomes?

Answer 2

All cells have chromosomes with million of base pairs. Some also have plasmids.

> Bacteria usually have single circular chromosome
Eukaryotes cells usually have multiple linear chromosomes.

Question 3

Plasmid

Answer 3

Smaller pieces of circular, double stranded DNA independent of the chromosome

Question 4

Central Dogma of Biology

Answer 4

All living organisms perform DNA replication, transcription, and translation. Which as a whole is the flow of genetic information from one cell to another

Question 5

Name some characteristics of genomes can be used to identify microbes

Answer 5

> Sequence of bases
Presence of plasmids
Size

Question 6

Replication

Answer 6

Copying of genetic information during cell division so each daughter cell has the information

Question 7

Transcription

Answer 7

The information in DNA is used to make RNA

The process of expressing the information begins

Question 8

Translation

Answer 8

The RNA is used to make polypeptides

Question 9

Mutate or Mutation

Answer 9

A change in DNA sequence and as these changes accumulate over time, different strains of a species or different species evolve

Question 10

Horizontal Gene Transfer

Answer 10

To gain or receive genetic material from other cells

A mechanism through which many antibiotic resistance genes are spread

Question 11

Basic Concepts of DNA Replication

Answer 11

DNA replication occurs by using each of the strands of doubles stranded DNA (dsDNA) as templates to make new strands of DNA
>Parent (template) strands are separated
>DNA polymerase “reads” the template and makes a new strand of DNA that is complementary to the parent via Base pairing
>The process continues until the chromosome has been copied

Question 12

Why are antibiotic used to target bacterial replication?

Answer 12

Antibiotic target bacterial replication because bacteria have different proteins involved in DNA replication than eukaryotic cells, these are good targets for antibiotics. [TB 8.2]

Question 13

RNA polymerase function

Answer 13

Its purpose is to recognizes promoters of genes, and makes an RNA copy of the DNA via base paring . and ends when it reaches a terminator region

Question 14

What happens once RNA has been produce and transcription comes to an end?

Answer 14

The DNA template goes back to a double strand molecule and the produced RNA detach from the DNA strand.

Question 15

In cells RNA usually exist in what form?

Answer 15

A single strand molecule, although some viruses are double stranded RNA

Question 16

What structure preforms protein synthesis?

Answer 16

Ribosomes are imperative to protein synthesis (translation)

Question 17

When does translation begins?

Answer 17

When a ribosome recognizes a ribosome binding site and a start codon from which point RNA is read in groups of three bases…

Question 18

When does translation ends?

Answer 18

When a ribosome recognizes stop codon…

Question 19

What is a codon?

Answer 19

A group of three bases that instructs the ribosome which amino acid to add

Question 20

Why are antibiotic used to target bacterial translation?

Answer 20

Bacteria have different ribosomes than eukaryotes, they are good targets for antibiotics [TB 8.3]

Question 21

Gene regulation is regulated. TRUE or FALSE

Answer 21

Transcription, translation, and all protein activity must be regulated.
Unnecessary production or activity can waste energy and resources.

Most genes are regulated in response to environmental conditions
>Changes in metabolism based off nutrient levels
>Temperature, pH, osmolarity, etc
>Stress

Question 22

Regulatory Proteins

Answer 22

Bind to gene promoters to increase (induction) or decrease (repression) transcription or translation

Question 23

Virulence Proteins

Answer 23

Pathogens express these proteins when they encounter certain conditions to increase their effectiveness

Question 24

How do microbes sense the external environment?

Answer 24

Sensing external conditions using proteins in the membrane, which determine the proteins activity and gene expression

Question 25

How do mutations occur?

Answer 25

> Errors in DNA replication
Chemical changes in nitrogenous bases
Exposure to mutagenic chemicals

If these errors or changes or not repaired, they will be passed on to the next generation

Question 26

The outcome of genetic mutations can be …

Answer 26

Errors or changes that can result in negative, positive, or neutral effects.
If not repaired = passed on to the next generation.