T3M1

Question 1

Genes are made up of

Answer 1

DNA

Question 2

Genes contain the instructions to make

Answer 2

proteins

Question 3

Genes can vary in size from

Answer 3

few hundred DNA nucleotide bases to thousands

Question 4

Human genome project estimates humans have how many genes?

Answer 4

20,000- 25,000 genes that code for proteins (some coding for different versions of the same protein)

Question 5

Housekeeping genes are constitutively expressed

Answer 5

‘ON’ all the time includes: structural proteins, ribosomal
proteins etc.

Question 6

Regulated genes are expressed

Answer 6

only when needed (enzymes)

Question 7

Fastest way to express a gene

Answer 7

post-translational regulation

Question 8

Slowest way to express a gene

Answer 8

transcriptional control regulation

Question 9

Most efficient way to express a gene

Answer 9

transcriptional regulation

Question 10

Transcriptional Control

Answer 10

Ability of RNA polymerase to bind to or transcribe a gene

Question 11

Translational Control

Answer 11

Translation rates, lifetime of RNA

Question 12

Post-translational Control

Answer 12

Post-translational modifications which may change folding and/or activity

Question 13

What is needed for prokaryotic growth?

Answer 13

favourable temperature, nutrient rich environment with amino acids and carbohydrates

Question 14

The DNA of the bacterial nucleoid contains

Answer 14

the information that is required to orchestrate a
response to any change in the environment

Question 15

Housekeeping genes

Answer 15

genes that are required all of the time for normal functions

Question 16

Regulated genes

Answer 16

genes can be turned on and off on an as-needed basis

Question 17

What type of gene is constitutively
expressed, and always being transcribed and translated?

Answer 17

housekeeping genes

Question 18

Housekeeping gene examples

Answer 18

genes that are important for structural proteins of the cell, RNA and DNA polymerases and genes that are coding for ribosomal proteins

Question 19

Housekeeping genes allow for

Answer 19

constant maintenance of general cellular activities

Question 20

When exposed to a changing environment, bacterial cells can respond by

Answer 20

altering the expression pattern of some genes

Question 21

Regulated bacterial genes can be transcribed and translated to allow for

Answer 21

the production of important enzymes
or proteins that are needed to bring about
changes in growth and division

Question 22

Enzymes are required to

Answer 22

metabolize nutrients

Question 23

Prefered energy source of E.coli

Answer 23

glucose

Question 24

If we grow E. coli cells in an environment that
contains both glucose and the disaccharide
lactose

Answer 24

bacteria will still metabolize all the glucose before switching to utilizing lactose as a
fuel source

Question 25

What activates the switch between glucose and lactose use?

Answer 25

products of glucose metabolism

Question 26

Lactose is made up of

Answer 26

one molecule each of glucose and galactose

Question 27

Enzyme that can metabolize lactose to produce glucose and galactose

Answer 27

B-galactosidase

Question 28

B-galactosidase is produced by

Answer 28

turning on transcription of the B-galactosidase gene when there is lactose available and no glucose available

Question 29

In the 1960's, Francois Jacob and Jacques Monod investigated

Answer 29

how E. coli are able to produce the B-galactosidase that is needed for lactose metabolism

Question 30

Jacob and Monod observed that the production of the B-galactosidase enzyme is dependent upon

Answer 30

the presence of lactose in the environment

Question 31

Jacob and Monod experiments

Answer 31

grew E. coli in a lactose-free medium, added lactose to the medium, and then removed it again. At the same time, they measured the amount of B- galactosidase enzyme produced in the cultured cells

Question 32

Jacob and Monod found from their experiment

Answer 32

amount of B-galactosidase protein produced by the E. coli cells began to steadily increase in response to the addition of lactose to the growth media. They also saw that the production of the B-galactosidase ceased once the lactose was removed

Question 33

Jacob and Monod results

Answer 33

lactose in the growth medium induced expression of the B-galactosidase gene

Question 34

Further research from Jacob and Monod led to

Answer 34

an explanation of the mechanisms that control B-galactosidase gene expression

Question 35

Who won Nobel Prize in Physiology or Medicine in 1965 for their work on the regulation of gene expression?

Answer 35

Jacob and Monod

Question 36

The term gene expression means

Answer 36

functional product of the gene is made, modified and activated

Question 37

Protein coding genes

Answer 37

transcription, translation, and protein modification must be completed

Question 38

Protein coding distinct levels of regulation

Answer 38

- transcriptional control to allow for the transcription of DNA to mRNA - translational control to allow for the translation of mRNA to proteins - post-translational control to allow for modifications and activation of produced proteins

Question 39

The regulation of the expression of an activated protein must take into consideration

Answer 39

how each of these levels of control are modified

Question 40

Transcriptional regulation controls

Answer 40

the amount of messenger RNA that is produced in the cell

Question 41

Activation of transcription requires

Answer 41

proteins bind to a region near the beginning of the gene, the promoter, and increase the binding of the enzyme, RNA polymerase

Question 42

By controlling the binding of proteins to the promoter, the cell can

Answer 42

activate or inhibit transcription

Question 43

Initiation of translation in eukaryotes occurs by

Answer 43

the binding of the ribosome to the 5’ end or 5’CAP of the mRNA

Question 44

Initiation of translation in prokaryotes

Answer 44

the ribosome will bind to and initiate translation at the specific Shine-Dalgarno sequences

Question 45

The rate at which translation occurs will affect

Answer 45

the amount of protein that is produced

Question 46

The amount of protein produced depends upon

Answer 46

the stability of the mRNA (If the mRNA is quickly degraded, then very little protein will be made)

Question 47

What allows the polypeptide chain to be folded into a functional three-dimensional structure?

Answer 47

post-translational control mechanisms

Question 48

Post-translational regulation allows the cell to

Answer 48

have a stockpile of protein in the cell that is simply inactive

Question 49

In transcriptional regulation, expression of a functional protein requires that

Answer 49

the cell activate transcription, complete translation, and finally modify the protein product

Question 50

Transcriptional regulation is often prevalent with

Answer 50

more drastic environmental changes that a cell can be exposed to

Question 51

Why is transcriptional regulation most efficient?

Answer 51

the cell does not waste any energy or resources making a mRNA or polypeptide