TRANSCRIPTION

Question 1

Synthesis of RNA using DNA as a template

Answer 1

TRANSCRIPTION

Question 2

possible products of transcription

Answer 2

mRNA
rRNA
tRNA
Addtnl RNA molecules (noncoding)

Question 3

for structural, catalytic and regulatory functions

Answer 3

noncoding RNAs

Question 4

sequences of amino acids

Answer 4

mRNA

Question 5

mRNA is ____% of the entire RNA

Answer 5

⁓2%

Question 6

TRANSCRIPTION | FEATURES

only particular genes or group of genes are transcribed at any one time

Answer 6

MORE SELECTIVE

Question 7

TRANSCRIPTION | FEATURES

phases of transcription

Answer 7

initiation
elongation
termination

some includes activation

Question 8

TRANSCRIPTION | DIFFERENCE W DNA REPLI

primer needed?

Answer 8

no primer needed

Question 9

TRANSCRIPTION | DIFFERENCE W DNA REPLI

involves ____ of DNA molecules

Answer 9

limited segments

Question 10

TRANSCRIPTION | DIFFERENCE W DNA REPLI

Within transcribed segments, only ____ serves as a template for a particular RNA molecule

Answer 10

only 1 DNA strand

Question 11

% of rRNA in the entire RNA

Answer 11

⁓80%

Question 12

• smallest
• ⁓15% in the entire rna
• Has extensive intrachain base-pairing
• Serves as an adapter molecule that carries its specific amino acid

Answer 12

tRNA

Question 13

how many species of tRNA is involved during translation or protein synthesis

Answer 13

20

each tRNA correspond to 1 amino acid

Question 14

tRNA

There is at least ____ of tRNA molecule for each of the 20 amino acids found in proteins

Answer 14

one specific type

Question 15

smaller rRNA

prokar or eukar

Answer 15

prokaryotic

Question 16

what do you call the part that the amino acid binds to

Answer 16

acceptor arm

Question 17

amino acids will be attached to the ____ end

Answer 17

3’

Question 18

a tRNA that carries an amino acid

Answer 18

active / charged tRNA

Question 19

smallest component of RNA

Answer 19

mRNA

Question 20

Most heterogeneous based on size and base sequence

Answer 20

mRNA

Question 21

carries genetic information from DNA -> protein

Answer 21

coding RNA

Question 22

SYNTHESIS OF RNA

• Reads DNA template strand in 3’ -> 5’ direction
• Hence: 5’ -> 3’ polymerase action
• Lacks a separate proofreading 3’ -> 5’ exonuclease active site

Answer 22

DNA DEPENDENT RNA POLYMERASE

DdRP

Question 23

SYNTHESIS OF RNA

requirements for DNA DEPENDENT RNA POLYMERASE

Answer 23

DNA template
Substrates: ATP GTP UTP CTP
Mg2+, Zn2+

Question 24

RNA POLYMERASE | CORE ENZYME

required for enzyme assembly

Answer 24

α, Ω

Question 25

# **RNA POLYMERASE | CORE ENZYME** needed for **template binding** has **polymerase activity** 5' -> 3'

Answer 25

β

Question 26

# **RNA POLYMERASE** * 2 α, 1 β, 1 β′, and 1 Ω * **lacks specificity** (that is, it **cannot recognize** the **promoter region** on the DNA template).

Answer 26

core enzyme

Question 27

# **RNA POLYMERASE** * **sigma subunit (sigma factor) ** * **enables** RNA polymerase to **recognize promoter regions** on the DNA

Answer 27

holoenzyme

Question 28

# **DIRECTION** DNA **template** strand

Answer 28

3' - 5'

Question 29

# **DIRECTION** DNA **nontemplate** / **Coding** strand

Answer 29

5' - 3'

Question 30

# **DIRECTION** RNA transcript

Answer 30

5' - 3'

Question 31

**Each nucleotide** in the **newly formed RNA** undergoes ____

Answer 31

base pairing

Question 32

**PROKARYOTIC** gene transcription

Answer 32

initiation elongation termination

Question 33

# **PROKARYOTIC GENE TRANSCRIPTION** product

Answer 33

primary transcript

Question 34

# **PROKARYOTIC GENE TRANSCRIPTION** RNA polymerase ____ a **primer** to **initiate** synthesis

Answer 34

does not require

Question 35

# **PROKARYOTIC GENE TRANSCRIPTION** **binds** to a **promoter region** of the DNA

Answer 35

holoenzyme portion

Question 36

# **PROKARYOTIC GENE TRANSCRIPTION** **directs** the **transcription** of **adjacent segments** of DNA (genes)

Answer 36

promoter

Question 37

# **PROKARYOTIC GENE TRANSCRIPTION** promoter region

Answer 37

-35 sequence pribnow box

Question 38

# **EUKARYOTIC GENE TRANSCRIPTION** promoter region

Answer 38

TATA or Hogness box, -25 CAAT box, -70 to 80

Question 39

* **Local unwinding** of the DNA **continues** mediated by the polymerase * RNA polymerase synthesizes RNA using **nucleoside monophosphates**, releasing pyrophosphate each time * **Direction** of the product: **5’ - 3’** RNA transcript

Answer 39

elongation

Question 40

# **ELONGATION** **direction** of the product

Answer 40

5' - 3'

Question 41

Elongation of RNA **continues** until a ____ is reached

Answer 41

terminal signal

Question 42

# **TERMINATION** occurs **without** additional proteins

Answer 42

INTRINSIC

Question 43

# **TERMINATION | INTRINSIC** **p-independent** - requires formation of a ____

Answer 43

HAIRPIN LOOP[

Question 44

# **TERMINATION** **requires** p protein to **release** RNA from DNA (**signaling** that there is already termination)

Answer 44

p-dependent

Question 45

# **TERMINATION** with **helicase activity**: **separates** the **RNA-DNA hybrid** helix, causing **release** of the RNA

Answer 45

p protein

Question 46

# **EUKARYUOTIC GENE TRANSCRIPTION** found in **rRNA** (**nucleolus**)

Answer 46

Pol I

Question 47

# **EUKARYUOTIC GENE TRANSCRIPTION** important in the **synthesis** of mRNA, and **noncoding** RNAs (**lncRNA**, **miRNA**, **snRNA**)

Answer 47

POL II

Question 48

# **EUKARYUOTIC GENE TRANSCRIPTION** **tRNA**, **5S rRNA**, some **snRNA** and **snoRNA**

Answer 48

POL III

Question 49

# **EUKARYUOTIC GENE TRANSCRIPTION** **Resembles** the **bacterial RNA pol**

Answer 49

RNA POLYMERASES (mitochondria)

Question 50

# **EUKARYUOTIC GENE TRANSCRIPTION** **Required** for the **assembly** of a **transcription initiation complex** at the promoter and the **determination** of which genes are **to be transcribed**

Answer 50

transcription factors

Question 51

# **POST-TRANSCRIPTIONAL MODIFICATIONS** Modification of the **primary transcript** (pre-rRNA to different **intermediate-sized pieces** of rRNAs)

Answer 51

rRNA

Question 52

**post transcriptional modificatons** happen via

Answer 52

ribonucleases

Question 53

# **POST-TRANSCRIPTIONAL MODIFICATIONS** **Sequences** at **both ends** of the molecule are **removed**, and, if present, an **intron** is **removed** from the **anticodon loop** by **nucleases**.

Answer 53

tRNA

Question 54

# **POST-TRANSCRIPTIONAL MODIFICATIONS** a. Addition of a **5’ cap** b. Addition of a **3’-poly-A tail** c. RNA **Splicing**

Answer 54

mRNA

Question 55

# **POST-TRANSCRIPTIONAL MODIFICATIONS** ADDITION OF A 5' CAP: The **cap** is a ____ **attached to** the **5′- terminal end** of the mRNA through an unusual **5′→5′-triphosphate linkage** that is **resistant to most nucleases**

Answer 55

7-METHYLGUANOSINE

Question 56

# **POST-TRANSCRIPTIONAL MODIFICATIONS** ADDITION OF A 5' CAP: The **cap** is a **7-methylguanosine attached to the** ____ of the mRNA through an **unusual 5′→5′-triphosphate linkage** that is **resistant to most nucleases**

Answer 56

5' TERMINAL END

Question 57

# **POST-TRANSCRIPTIONAL MODIFICATIONS ADDITION OF A 5' CAP: The **cap** is a **7-methylguanosine attached to the 5′- terminal end** of the mRNA through an **unusual** ____ that is **resistant to most nucleases**

Answer 57

5' - 5' TRIPHOSPHATE LINKAGE

Question 58

# **POST TRANSCRIPTIONAL MODIFCATIONS** ADDITION OF A 5' CAP: The **cap** is a **7-methylguanosine attached to the 5′- terminal end** of the mRNA through an unusual **5′→5′-triphosphate linkage** that is **resistant** to ____

Answer 58

MOST NUCLEASES

Question 59

# **POST TRASNCRITPIONAL MDOFICATOOIN** * a **chain** of **40–250 adenylates** (adenosine monophosphates) attached to the **3′-end** * **not transcribed** from the DNA * added by the nuclear enzyme, **polyadenylate polymerase** * Purpose - To **terminate** transcription - Tails help **stabilize** the **mRNA**, **facilitate its exit** from the nucleus, and **aid in translation** - After the mRNA enters the cytosol, the poly-A tail is gradually shortened.

Answer 59

ADDITION OF A 3'-POLY-A TAIL

Question 60

# **POST TRANSCRIP MODIF | ADDITION OF 3'-POLY-A TAIL** a **chain** of ____ **adenylates** attached to **3' end**

Answer 60

40 - 250

Question 61

# **POST TRANSCRIP MODIF | ADDITION OF 3'-POLY-A TAIL** **added** by the **nuclear enzyme** ____

Answer 61

polyadenylate polymerase

Question 62

# **POST TRANSCRIP MODIF** **removal of introns** (intervening sequence) from the **primary transcript** and **joining of exons** to form a **continuous sequence** that specifies a functional polypeptide

Answer 62

RNA splicing

Question 63

intervening sequence

Answer 63

introns

Question 64

molecular complex that **facilitates splicing**

Answer 64

spliceosome