trancription

Question 1

is the copying of one strand of DNA into RNA by a
process similar to that of DNA replication.

Answer 1

Transcription

Question 2

• enzyme that catalyzes the process

Answer 2

RNA Polymerase

Question 3

single type of RNA polymerase catalyzes the synthesis of all
RNA.

Answer 3

Prokaryotes

Question 4

binds the RNA polymerase to the
promoter region enabling it to transcribe the DNA

Answer 4

sigma subunit-

Question 5

eukaryotes
RNA Polymerase I
RNA Polymerase II
RNA Polymerase III

Answer 5

RNA Polymerase I - synthesis of rRNA
RNA Polymerase II- synthesis of mRNA, snRNA
RNA Polymerase III- synthesis of tRNA, snRNA

Question 6

needed by RNA polymerase to
bind to the promoter allowing RNA polymerase to bind to the
DNA and read it

Answer 6

General Transcription Factor-

Question 7

location of ribosomal RNA synthesis.

Answer 7

Nucleolus

Question 8

RNA polymerase binds to a specific region of DNA called
the promoter.

Answer 8

Initiation

Question 9

contain specific sequences that help recruit
RNA polymerase and determine which strand of DNA is
transcribed

Answer 9

Promoters

Question 10

Prokaryotic cells

Answer 10

-35 region
-10 region (Pribnow box)
+ 1 region

Question 11

Eukaryotic cells

Answer 11

TATA
CAAT
GC

Question 12

precess wherein RNA polymerases read the template strand

Answer 12

Elongation

Question 13

inhibit RNA polymerase in Eukaryotes

Answer 13

Amanitin

Question 14

inhibit RNA polymerase in Prokaryotes

Answer 14

Rifampicin

Question 15

Once RNA polymerase is bound to the promoter

Answer 15

Opens the DNA
Stabilizes the ssDNA
Unwinds the DNA double helix
begins reading the DNA from 3’ to 5’
synthesizing mRNA in the 5’ to 3’ direction.

Question 16

Transcription continues until RNA polymerase encounters a
termination signal in the DNA sequence.

Answer 16

Termination

Question 17

cause RNA polymerase to detach from the
DNA template, releasing the newly synthesized RNA molecule.

Answer 17

Termination signals

Question 18

causes the RNA polymerase to
break away from the DNA

Answer 18

Rho-dependent protein

Question 19

Hit the areas of inverted repeats creating hairpin loop that
will trigger cleavage enzymes and cleave away from the
RNA polymerase

Answer 19

Rho-independent termination

Question 20

activates particular enzymes and cleaves the RNA polymerase
from the DNA

Answer 20

polyadenylation signal (AAUAAA)/ PolyA Site

Question 21

POSTTRASCRIPTIONAL MODIFICATION OF MRNA

Answer 21

1.Capping
2.Polyadenylation
3.Splicing
4. RNA editing

Question 22

A modified nucleotide, usually 7-methylguanosine, is added to the 5’ end
of the mRNA molecule.

Answer 22

Capping

Question 23

protects the mRNA from exonuclease degradation and helps in
the initiation of translation.C

Answer 23

CAP

Question 24

A polyadenine (poly-A) tail is added to the 3’ end of the mRNA molecule.

Answer 24

Polyadenylation

Question 25

stabilizes the mRNA and is important for mRNA export from the nucleus and translation efficiency.

Answer 25

poly-A tail

Question 26

Many pre-mRNA molecules contain ___________, non-coding regions that must be removed to produce mature mRNA.

Answer 26

introns

Question 27

________ is the process by which introns are removed and ________ (coding regions) are joined together to form a continuous mRNA molecule

Answer 27

SPLICING EXON

Question 28

In some cases, the sequence of the mRNA molecule is altered after transcription by processes such as deamination or nucleotide insertion or deletion.

Answer 28

RNA editing

Question 29

DNA sequences which increases the transcription rate

Answer 29

Enhancers

Question 30

- binds to the enhancer and causes a looping to the DNA

Answer 30

Specific Transcription Factor

Question 31

DNA sequences which decreases the transcription rate

Answer 31

Silencers

Question 32

transcription is controlled by seven major strategies: a

Answer 32

alternative σ factors, RNA polymerase switching, antitermination, enhancers, operon, transcription attenuation, and riboswitch

Question 33

involve the change of transcription machiner

Answer 33

Alternative σ factors, RNA polymerase switching, and antitermination

Question 34

involve the regulation of groups of functionally related genes.

Answer 34

Operon, transcription attenuation and riboswitch

Question 35

are the DNA elements that bind protein factors.

Answer 35

Enhancers

Question 36

GENERAL STRUCTURE OF AMINO ACIDS

Answer 36

amino group carboxyl group α-carbon hydrogen R group

Question 37

determines the identity of the particular amino acid.

Answer 37

R group

Question 38

important for the processes that drive protein chains to fold to form their natural and/or functional structures.

Answer 38

Nonpolar Amino Acids

Question 39

The R group of polar uncharged amino acids can form hydrogen bonds with water and play a variety of nucleophilic role in enzyme reactions

Answer 39

Polar Amino Acid

Question 40

They have carboxyl groups in their side chains in addition to the one present in all amino acids.

Answer 40

Acidic Amino Acids

Question 41

These negatively charged amino acids bind metal ions for structural or functional purposes

Answer 41

Acidic Amino Acids

Question 42

These have a positively charged side chain at physiological pH

Answer 42

Basic Amino Acids

Question 43

The crucial feature of amino acids that allows them to polymerize to form peptides and proteins is the existence of their two chemical groups

Answer 43

amino (-NH+3) carboxyl (-COO-) groups.

Question 44

The peptide bond is an amide bond formed in a____________ between the -COO– group of one amino acid and the-NH+3 group of another amin

Answer 44

The peptide bond is an amide bond formed in a head-to-tail fashion between the -COO– group of one amino acid and the-NH+3 group of another amin

Question 45

AMINO ACIDS CAN JOIN THROUGH PEPTIDE BONDS TO FORM POLYMERS causing q

Answer 45

This reaction eliminates a water molecule and forms a covalent amide linkage.

Question 46

polymers consisting of amino acids linked by covalent peptide bond

Answer 46

Proteins

Question 47

Four levels of protein structure

Answer 47

1. Primary structure The linear sequence of amino acids in a protein chain. 2. Secondary structure The local folding patterns within a protein chain, often forming alpha helices or beta sheets stabilized by hydrogen bonds. 3. Tertiary structure The overall three-dimensional shape of a protein, determined by interactions between amino acid side chains, including hydrogen bonds, disulfide bonds, hydrophobic interactions, and electrostatic interactions. 4. Quaternary structure The arrangement of multiple protein subunits (polypeptide chains) and any associated non-protein molecules into a functional protein complex. Not all proteins have quaternary structure; it only applies to proteins with multiple subunits.

Question 48

3 CLASSES OF PROTEINS BASED ON STRUCTURE AND SOLUBILITY

Answer 48

1.Fibrous Proteins 2. Globular Proteins 3. Membrane Proteins

Question 49

These proteins have elongated, fibrous structures and are typically insoluble in water.

Answer 49

1.Fibrous Proteins

Question 50

These proteins have compact, spherical shapes and are usually soluble in water.

Answer 50

2. Globular Proteins

Question 51

proteins that perform a wide range of functions within the cell, including enzymatic catalysis, transport, and regulation.

Answer 51

2. Globular Proteins

Question 52

proteins that provide structural support and strength to cells and tissues.

Answer 52

1.Fibrous Proteins

Question 53

These proteins are associated with cell membranes and play crucial roles in cell signaling, transport of molecules across membranes, and cell-cell recognition.

Answer 53

3. Membrane Proteins

Question 54

They can have various structures, including integral membrane proteins that span the lipid bilayer and peripheral membrane proteins that are attached to the membrane surface

Answer 54

3. Membrane Proteins

Question 55

is composed of ribonucleotide triplets, known as codons, which specify amino acids.

Answer 55

The genetic code

Question 56

Each codon consists of three ribonucleotide bases and corresponds to a specific amino acid.

Answer 56

Bases: A, G, C, U

Question 57

THE GENETIC CODE how many codnonds

Answer 57

61 codons- code for amino acids 3 codons- stop codons

Question 58

wobble effect refers to a phenomenon in the genetic code where the third nucleotide position of a codon can exhibit flexibility or “wobble” in base pairing during translation.

Answer 58

wobble effect

Question 59

is possible due to the degeneracy of the genetic code, where multiple codons can code for the same amino acid.

Answer 59

wobble effect