Exam 1

Question 1

What are the concerns related to the use of GE?
A) New genes introduced in genetically engineered organism may have unpredictable effects on its physiology and biochemistry

B) Transgenic animals can pass their transgene to the offspring

C) Foreign genes may have unexpected and potentially dangerous effects when placed in a genetic environment that is different from what is natural for them

D) All choices are correct

Answer 1

D) All the above

Question 2

What is the correct chronological order of events?
i. Watson and Crick elucidate the double helix structure of DNA

ii. Friedrich Miescher isolates DNA

iii. Berg, Boyer and Cohen develop the first recombinant DNA molecule

iv. Arber provides evidence for restriction enzyme

v. Gellert discovers DNA ligase enzyme

Answer 2

ii→i→iv→v→iii

Question 3

In the following biochemical reaction, what are the correct governing equations?
A)
dx/dt = dy/dt = k+xy - k-z
dz/dt = -k+xy + k-z

B)
dx/dt = dy/dt = k+xy
dz/dt = k-z

C) None of these answers are correct

D)
dx/dt = dy/dt = -k+xy + k-z
dz/dt = k+xy - k-z

Answer 3

D)
dx/dt = dy/dt = -k+xy + k-z
dz/dt = k+xy - k-z

Question 4

Which of the following statements are correct? In the equation: x(t) = xe^kt

Answer 4

If k>0, then it represents exponential growth

Question 5

What is/are the correct equation(s) that represent the Conservation Law? Select all correct answers.
d(c+a)/dt = 0

d(b+a)/dt = 0

d(b+c)/dt = 0

d(a-c)/dt = 0

Answer 5

d(c+a)/dt = 0
d(b+a)/dt = 0

Question 6

When considering Michaelis Menten Kinectics’ quasi steady state approximation, what is/are true about the significance of Ɵ?
A) Ɵ is the substrate concentration at which the reaction rate is at half of the maximum

B) Ɵ is a direct measure of the substrate ability for the enzyme (i.e., a large Ɵ indicates that the reaction rate will arrive maximum more quickly)

C) Ɵ is independent on both enzyme and substrate, as well as conditions such as temperature and pH.

D) A and C

Answer 6

A) Ɵ is the substrate concentration at which the reaction rate is at half of the maximum

Question 7

What is true about Michaelis Menten Kinetics?
A) It is used with quasi steady state approximation when the complex amount stays constant

B) It improves modeling of reaction that does not actually have infinitively exponential growth in real experiment when reactants are limited

C) Both A and B

D) None of the above

Answer 7

C) Both A and B

Question 8

Which statement is correct about competitive inhibition?
A) primary substrate can bind to the enzyme thus preventing the inhibitor from doing it. The result is that no product can be created.

B) None of these statements are correct

C) Antihistamines are competitve inhibitors of histamines at the histamine receptor

D) Substrate formation rate can be modeled as:

Answer 8

C) Antihistamines are competitve inhibitors of histamines at the histamine receptor

Question 9

Positively cooperative binding:

Answer 9

n>1, the catalyst’s affinity for ligands increases with more ligands bound to it

Question 10

Negatively cooperative binding

Answer 10

n<1, the catalyst’s affinity for ligands decreases with more ligands bound to it

Question 11

Noncooperative binding

Answer 11

n=1, catalyst affinity for ligands is unaffected by the number of ligands bound to it

Question 12

In a gene circuit diagram, arrows indicate

Answer 12

promotion of a gene

Question 13

In a gene circuit diagram, T-shaped ends indicate

Answer 13

inhibition of a gene

Question 14

Gene

Answer 14

A specific nucleotide sequence that is transcribed for RNA

Question 15

Structural gene

Answer 15

Coding sequence for mRNA in eukaryotes, coregulated by operon

Question 16

Lac Operon

Answer 16

Bacteria operon (in Escherichia coli) responsible for metabolism of lactose to glucose and galactose

Question 17

transcriptional terminator

Answer 17

Signals RNA polymerase to stop transcription, downstream of the coding sequence

Question 18

Exons

Answer 18

Coding segments of eukaryotic DNA for RNA

Question 19

Introns

Answer 19

Noncoding segments of nucleic acid between coding sequences, removed from primary transcript after RNA polymerase has bound to the promoter and the entire eukaryotic structural gene is transcribed, which links Exons together, eukaryotes

Question 20

Eukaryote RNA transcription differs because it

Answer 20

has Intron and Exon sequences, ends modified and removed by RNA splicing

Question 21

Synthetic biology and genetic circuit uses

Answer 21

logic gates

Question 22

Logic gates are built in gene circuits by

Answer 22

altering or introducing connections between genetic components to make novel regulatory networks

Question 23

Gene logic gates interpret logical values from

Answer 23

molecular concentrations

Question 24

NOT gate

Answer 24

changes its output to the opposite state of its input (1 to 0, 0 to 1)

Question 25

AND gate

Answer 25

takes in 2 inputs and only outputs True if both inputs are True (outputs 1 only if both signals are 1)

Question 26

OR gate

Answer 26

gives a true signal if one or both of its inputs are true

Question 27

NAND gate

Answer 27

output is 0 when all inputs are 1 and 1 for all other inputs, inverted AND gate

Question 28

NOR gate

Answer 28

output is 0 when any input is 0, inverted OR gate

Question 29

X in logic gates means

Answer 29

exclusive

Question 30

XOR gate

Answer 30

If a single input is true, the output is true, if both or none are true, the output is false

Question 31

XNOR gate

Answer 31

If both or neither input is true, the output is true, inverted XOR

Question 32

Exclusive gates are indicated by

Answer 32

an extra line

Question 33

Inverted gates are indicated by

Answer 33

a little circle

Question 34

Logic gates can be used to control genetic circuits with

Answer 34

external inputs (ligands, etc)

Question 35

Tet-off system

Answer 35

In the presence of doxycycline, tet transactivators (tTAs) cannot bind to the tet-operator (tetO) sequence to induce target gene (transgene) expression. Without Dox, tTAs bind to the tetO sequence to drive target gene expression

Question 36

Tet-on system

Answer 36

reverse tet transactivators (rtTAs) bind to the tet-operator (tetO) in the presence of Doxycycline to induce transgene expression. Incontrast, in the absence of Dox, rtTAs cannot bind to the tetO and expression does not occur

Question 37

Operon

Answer 37

a functioning unit of genomic DNA containing a cluster of genes under the control of a single promoter, where all genes are transcribed on the same mRNA (must be co-transcribed!)

Question 38

Promoter

Answer 38

specific region of a gene where RNA polymerase can bind and begin transcription, indicates what mRNA should be transcribed, upstream of the coding sequence

Question 39

Regulator

Answer 39

control the operator gene in conjunction with inducers and corepressors, not necessarily adjacent to the gene it controls, but produces proteins called repressors that bind to the operator gene and prevent transcription

Question 40

operator

Answer 40

repressors bind to it, placed between promoter and operon so that repressors physically block transcription

Question 41

Lac Operon's two regulatory proteins

Answer 41

Catabolic Activator Protein (CAP) and Lac Repressor Protein

Question 42

Negative regulation

Answer 42

a repressor protein binds to an operator to prevent a gene from being expressed

Question 43

positive regulation

Answer 43

the regulation of gene expression by the binding of an activator protein to DNA

Question 44

Catabolic Activator Protein (CAP)

Answer 44

forms a complex with cAMP to bind to operator site, encourages transcription when glucose is not present (and cAMP is subsequently high)

Question 45

Lac Repressor Protein

Answer 45

binds to operator to prevent transcription when lactose is not present, binds to allolactose which prevents repression

Question 46

cAMP is only present when

Answer 46

glucose in the cell is low

Question 47

Lac operon natural behavior

Answer 47

transcription of lactase when glucose is low and lactose is present but not when glucose is high and/or lactose is low

Question 48

lac operon is induced

Answer 48

in presence of lactose and absence of glucose, otherwise inert

Question 49

The lac operon is an example of

Answer 49

negative regulation because it is repressed in the absence of lactose

Question 50

lacO

Answer 50

operator for lac operon, double regulated by CAP and Lac repressor protein

Question 51

allosteric regulation

Answer 51

When a protein's function at one site is affected by the binding of a regulatory molecule to a separate site (ex. Lac repressor protein and allolactose)

Question 52

Allolactose

Answer 52

Inducer of the lac operon; metabolite of lactose

Question 53

How to solve first order differential equations

Answer 53

separate variables, integrate both sides, transform equation

Question 54

equations for x+y=>z with unidirectional rate constant k

Answer 54

dx/dt=-kxy, dy/dt=-kxy, dz/dt=kxy

Question 55

equations for x+y=>z with bidirectional rate constants k+ and k-

Answer 55

dx/dt= -(k+)xy + (k-)z dy/dt= -(k+)xy + (k-)z dz/dt= -(k-)z + (k+)xy

Question 56

Michaelis-Menten equation

Answer 56

v = (vmax [S])/(Km + [S]) rate equation for a one-substrate enzyme-catalyzed reaction, assumes steady state for enzyme-substrate complex, describes rate of reaction

Question 57

Conservation laws for x+y=>z

Answer 57

d(x+z)/dt = d(y+z)/dt = 0

Question 58

steady state approximation

Answer 58

assumes steady concentration of intermediate or enzyme-substrate complex, allows reduction to a scalar ODE, used by michaelis menten

Question 59

In michaelis menten kinetics, theta is

Answer 59

the amount of substrate when the rate of reaction is half of the maximum, dependent on enzyme, substrate and external conditions, inversely proportional to substrate affinity

Question 60

How does theta relate to substrate affinity?

Answer 60

inversely, small theta means a strong affinity as it means the reaction proceeds faster (reaches half-maximum rate quicker)

Question 61

True or false signals are determined by

Answer 61

concentration and threshold

Question 62

Inducers

Answer 62

external chemicals that interact with gene products, must be present above a concentration threshold to have an effect

Question 63

During DNA replication, if the base sequence in the template strand is 5'-AGGCTA-3', which is the correct base sequence in the growing strand?

Answer 63

3'-TAGCCT-5'

Question 64

What is/are true about Tet system? Select all correct answers A. Only Tet Off system exist B. Tet system is typically induced by tetracyclin C. Both Tet ON and Tet OFF systems exist D. Doxycycline can be used in place of tetracyclin to induce the Tet system

Answer 64

Tet system is typically induced by tetracyclin, Both Tet ON and Tet OFF systems exist, Doxycycline can be used in place of tetracyclin to induce the Tet system

Question 65

The phosphate is the ___ end

Answer 65

5' (Ph sound is the same as five)

Question 66

The hydroxyl is the ___ end

Answer 66

3'

Question 67

Which of the following is/are true about an operon? A. Regulator of an operon are genes that regulate the operator genes B. Regulator gene controls an operon, but it is not part of an operon C. Regulator of an operon is where repressor binds to interrupt RNA polymerase from transcribing genes D. Promoter is the nucleotide sequence in an operon that is recognized by RNA polymerase to initiate transcription for mRNA production

Answer 67

A. Regulator of an operon are genes that regulate the operator genes B. Regulator gene controls an operon, but it is not part of an operon D. Promoter is the nucleotide sequence in an operon that is recognized by RNA polymerase to initiate transcription for mRNA production

Question 68

Which of the following should be considered when one mathematically model a gene regulatory network with ordinary differential equation? A. Production and degradation rate of mRNA B. Production and degradation rate of protein C. Any positive feedback control that could increase the production rate of mRNA D. Any negative feedback control that could reduce the production rate of mRN

Answer 68

All are correct

Question 69

What is genetic engineering? A. All choices are correct B. It introduces genes that are foreign to the species C. It is the direct manipulation of an organism's genes by technological intervention/manipulation D. It is a term used to describe some modern techniques in molecular biology (recombinant DNA technology)

Answer 69

A. All choices are correct

Question 70

Genetic engineering is

Answer 70

Direct manipulation of genes through technology Describes some new techniques in modern biology like recombinant DNA technology techniques/technology used to modify organisms in order to get them to produce new substances or do new function Permanently changes genetic makeup of an organism

Question 71

Difference between genetic engineering and selective breeding

Answer 71

Selective breeding cannot introduce new genes to a species, while genetic engineering can. Breeding uses natural gene changes, while genetic engineering is artificial.

Question 72

Concerns with genetic engineering vs. selective breeding

Answer 72

Foreign genes can have unexpected and/or dangerous effects in new genetic environments, new genes can have unpredictable effects on physiology and biochemistry of genetically engineered organisms, which could be passed on to offspring

Question 73

Gregor Mendel (1822-1884)

Answer 73

investigated inheritance in pea plants by observing differences in various traits of the plants from generation to generation, leading to the idea that information needed to build an organism is packaged into units associated with specific dominant and recessive traits

Question 74

Gregor Mendel found two laws

Answer 74

Law of independent assortment and law of segregation

Question 75

law of independent assortment

Answer 75

the alleles of two (or more) different genes get sorted into gametes independently of one another

Question 76

law of segregation

Answer 76

a diploid organism passes a randomly selected allele for a trait to its offspring, such that the offspring receives one allele from each parent.

Question 77

During DNA replication, if the base sequence in the template strand is 5'-AGGCTA-3', which is the correct base sequence in the growing strand? A) 5'-UAGCCU-3' B) 5'-ATCGGA-3' C) 5'-AGGCTA-3' D) 5'-TAGCCT-3'

Answer 77

D) 5'-TAGCCT-3'

Question 78

What is/are false about Lac Operon? Select all correct answers. A) IPTG can be used in place of lactose to induce Lac operon B) Lac operon is ON when lactose is present while glucose is absent C) Lac operon is OFF when lac repressor is bound D) Lac operon is ON when glucose is present while lactose is absent

Answer 78

D) Lac operon is ON when glucose is present while lactose is absent

Question 79

What is the 5' end?

Answer 79

Phosphate

Question 80

What is true about Polymerase Chain Reaction (PCR)? Select the best answer. A) The starting material is DNA B) The starting material is RNA C) Each cycle of PCR doubles the amount of nucleic acid in the previous step D) Both A and C

Answer 80

D) Both A and C