L9 Nucleic Acid Replication and Protein Synthesis

Question 1

Genetics is the study of:

Answer 1

Gene expression

Question 2

(T/F) All proteins have their sequence of amino acids determined by the code of DNA on the original gene

Answer 2

True

Question 3

The “genetic code” consists of:

Answer 3

AGCT (adenine, guanine, cytosine, thymine)

Question 4

DNA is a double-stranded, helical nucleic acid with : (3)

Answer 4

Backbone of deoxyribose sugar and phosphate

Four nitrogenous bases (AGCT)

Question 5

RNA is a single-strand nucleic acid that has 3 different forms. It consists of (3):

Answer 5

Backbone ribose sugar and phosphate

Four nitrogenous bases (AGCU)

Question 6

The 3 common forms of RNA are:

Answer 6

rRNA (ribosomal)
mRNA (messenger)
tRNA (transfer) or ribosomes

Question 7

Nitrogenous bases are _ and _ structures

Answer 7

purines and pyrimidines

Question 8

____ are a nitrogenous base bonded to a ribose or deoxyribose sugar

Answer 8

Nucleosides

Question 9

Nucleotides are nucleosides bonded to one or more ____ groups

Answer 9

phosphate

Question 10

How are nucleotides bonded?

Answer 10

Bonded between a phosphate and sugar

Sugar-phosphate backbone

Question 11

How do nitrogenous bases form their specific couples?

Answer 11

Hydrogen bonds

Question 12

The code for a protein’s ____ ____ sequence is stored in DNA

Answer 12

amino acid

Question 13

The cell uses _____ to move the coded sequence away from DNA, keeping DNA’s involvement to a minimum, thus ______ the genes

Answer 13

mRNA; conserving

Question 14

mRNA is decoded in the _______ at ______, where proteins are ______ from the mRNA code

Answer 14

cytoplasm; ribosomes;translated

Question 15

DNA gets unzipped by _______ enzyme which also “reads” DNA code, and then _____ a mRNA strand from the revealed code

Answer 15

replicase; transcribes

Question 16

_______ is the “writing” of the DNA genetic code into mRNA (nucleic acid to nucleic acid) by ___ ___ ___

Answer 16

Transcription; RNA polymerase enzyme

Question 17

DNA packed into a cell’s nucleus is called:

Answer 17

Chromatin

Question 18

The DNA double helix wraps around a bundle of ____ ____, which then wraps into a ball-like structure called a _____

Answer 18

histone proteins; nucleosome

Question 19

The nucleosome forms the next level of structure by condensing into another helical structure called ____ _____

Answer 19

condensed fiber

Question 20

The spiral thread of the condensed fiber forms a larger level of structure as it bundles itself into:

Answer 20

chromatin

Question 21

List the structures of chromatin from smallest to largest:

Answer 21

histone proteins-> nucleosome-> condensed fiber -> chromatin

Question 22

Active chromatin that gets transcribed regularly and is less compacted is called:

Answer 22

Euchromatin

Question 23

Genetic code is that is conserved, almost never accessed for transcription and is densely packed:

Answer 23

Heterochromatin

Question 24

What is the chief protein component of chromatin?

Answer 24

Histones

Question 25

(T/F) Histones play a large role in gene regulation; Without them, DNA in chromosomes would be very long

Answer 25

True

Question 26

RNA transcription of protein code from DNA is much simpler than DNA replication, using only __ ___

Answer 26

RNA polymerase

Question 27

In transcription, these molecules find the site of code on the DNA that is to be transcribed, unzips the DNA, replicates the DNA using RNA nucleotides, and rezips the DNA

Answer 27

RNA polymerases

Question 28

The RNA produced from transcription will be processed by ___ ____ and ____ into either mRNA, tRNA or rRNA

Answer 28

splicing enzymes and ribozymes

Question 29

RNA polymerase is responsible for ____ DNA code into RNA, allowing protein codes to get to the ____ for ____ manufacture

Answer 29

transcribing; cytoplasm; protein

Question 30

Where is mRNA spliced and processed?

Answer 30

nucleus

Question 31

Once mRNA is made, it is transported out of the nucleus through ___ ___ and is moved to the ___ throughout the cell where that particular protein coded on the mRNA is needed

Answer 31

nuclear pores; ribosomes

Question 32

(T/F) mRNA can be used multiple times in the ribosome

Answer 32

True

Question 33

(T/F) DNA is only replicated when a cell divides

Answer 33

True

Question 34

How many clusters of enzymes are used to duplicate DNA for cell division?

Answer 34

2

Question 35

Step 1 in DNA Replication: | _______ enzyme untwists the secondary helix structure

Answer 35

Topoisomerase

Question 36

Step 2 in DNA Replication: A ____ untwists the primary helix structure by relieving the _____ bonding between bases. This separates the two strands. Binding proteins attach to the strands to keep them separated.

Answer 36

Helicase; hydrogen

Question 37

Step 3 in DNA Replication: | ___ ___ bonds free-floating nucleotides into the deoxyribose-sugar chain

Answer 37

DNA primase

Question 38

Step 4 in DNA Replication: | ___ ___ connects together the bits of newly created nucleotide chain

Answer 38

DNA ligase

Question 39

Step 5 in DNA Replication: | ___ ___ finished the bonding of nucleotides, and re-zips the strands as 2 ___ ___

Answer 39

DNA polymerase; Daughter strands

Question 40

Why do proteins need to continually be made and renewed?

Answer 40

To maintain tissue intregity

Question 41

Proteins are used for : 3

Answer 41

1. Enzymes to catalyze biochemical processes 2. Structure: muscle, glands, organs, etc 3. Function: hormones and messengers, metabolism, etc

Question 42

Step 1 in Protein Synthesis: Replication copies a protein code from DNA specific for the desired protein, writing the code in mRNA in a process known as:

Answer 42

Transcription

Question 43

Step 2 in Protein Synthesis: The mRNA is moved out of the cell nucleus to the ____, and is translated into a polypeptide by a ribosome in the process called:

Answer 43

Translation

Question 44

Step 3 in Protein Synthesis: The mRNA transcription information are "read" as _ nitrogenous bases at a time, called ____. These are unique for each of the 20 amino acids used to create proteins

Answer 44

3; codons

Question 45

Step 4 in Protein Synthesis: | The mRNA is brought into the ___, where it is translated by several _____ in a continuous chain of manufacture

Answer 45

cytoplasm; ribosomes | Ribosomes help "read" the codons

Question 46

Step 5 in Protein Synthesis: | ___ loaded with amino acids enter the active site in a ribosome and match their anticodon to the codon on _____.

Answer 46

tRNAS; mRNA | The line up of tRNA's amino acids are bonded into a protein chain, still in the active site of the ribosome

Question 47

Step 6 in Protein Synthesis: The new polypeptide is trimmed, modified and folded in the ______ or in an _____ to restructure it as a protein, and then protein is transported to its destination or out of the cell

Answer 47

Cytoplasm; organelle

Question 48

___ is constantly consumed to operate the enzyme cascades in protein synthesis

Answer 48

ATP

Question 49

(T/F) DNA code transcribes other information besides the actual protein sequence

Answer 49

True

Question 50

DNA code transcribes these 3 to tell the ribosome to begin to translate mRNA and when the protein code is over

Answer 50

Promotion codes Starter codons Termination codons

Question 51

Each codon is _ bases long, and codes for _ amino acid

Answer 51

3; 1

Question 52

This code designates where the 3-base codon chain begins

Answer 52

Starter codon

Question 53

Once the initial strand of mRNA is created in the nucleus, it is modified by enzymes to put caps on the ends of the ___ ___ and goes through internal splicing of exons and introns by ___

Answer 53

nucleic acid; ribozymes

Question 54

The exon codes are used to:

Answer 54

Make protein

Question 55

The intron codes are used to:

Answer 55

Create a mature mRNA by being spliced out of the mRNA; The mature mRNA is then sent to ribosomes for translation into protein

Question 56

___ carries a 3-base anti-codon

Answer 56

tRNA

Question 57

tRNA is specific to:

Answer 57

amino acid and codon

Question 58

An enzyme called __ __ __ recycles tRNA that have given up their amino acid by reloading these emptied tRNA into the ___ with their specific amino acid

Answer 58

Aminoacyl tRNA synthetase

Question 59

mRNA is produced in the ___, matured and transported into the cytoplasm, objective being to link with _____

Answer 59

nucleus, ribosomes

Question 60

Ribosomal 30 and 50 subunits are available on ___ or ___ _____

Answer 60

RER; float freely

Question 61

___ is sensed by 30s and 50s subunits; the subunits join to form a ribosome protein factory

Answer 61

mRNA

Question 62

The mRNA moves into the _ and _ active site of the ribosome

Answer 62

A and P

Question 63

___'s loaded with respective amino acids move in and match their anticodons to the codons of the ___

Answer 63

tRNA; mRNA

Question 64

____ _____ form between the amino acids from the _ site to the _ site by enzymatic action

Answer 64

Peptide bonds; A P

Question 65

mRNA shifts one set of ___ in the active site, allowing the next tRNA/ amino acid combination in, and the fusion of amino acids continues until stopped

Answer 65

codons

Question 66

List 3 reasons why translation would discontinue:

Answer 66

1. Termination codon is found in the mRNA 2. The emptied tRNA's go out and pick up their amino acids, being recycled by aminoacyl tRNA synthetase 3. The polypeptide chain is pushed out into the cytoplasm where it is folded or modified into a protein, often in the Golgi complex

Question 67

The __ and __ are where vitamins and other cofactors are inserted into protein to create a ___ for use or a ___ for storage

Answer 67

Golgi and ER | Holoenzyme; Zymogen