Protein Synthesis

Question 1

Genes

Answer 1

a sequence of nucleotides in DNA that perform a specific function, such as coding, for a particular protein

Question 2

Proteins

Answer 2

complex molecules composed of one or more polypeptide chains made of amino acids and folded into specific three-dimensional shapes that determine protein function

Question 3

Amino Acid

Answer 3

the monomer unit of a polypeptide chain that is composed of a carboxylic acid, an amino group, and a side group that differentiates it from other amino acids

Question 4

Transcription

Answer 4

the process in which DNA is used as a template for the production of complementary messenger RNA molecules

Question 5

Translation

Answer 5

the process by which a ribosome assembles amino acids in a specific sequence to synthesize a specific polypeptide coded by messenger RNA

Question 6

mRNA

Answer 6

the end product of transcription of a gene, mRNA is translated by ribosomes into protein

Question 7

Codons

Answer 7

sequence of three bases in DNA or complementary mRNA that serves as a code for a particular amino acid

Question 8

Stop Codons

Answer 8

specific codons that signal the end of translation to a ribosome

Question 9

Start Codon

Answer 9

specific codon (AUG) that signals to the ribosome that the translation commences at that point

Question 10

RNA Polymerase

Answer 10

enzyme that transcribes DNA into complementary mRNA

Question 11

Promoter

Answer 11

sequence of DNA that binds RNA polymerase upstream of a gene

Question 12

rRNA (ribosomal RNA)

Answer 12

a form of RNA that binds with ribosomal protein to form ribosomes

Question 13

Poly-A Tail

Answer 13

a string of 200-300 adenine base pairs at the end of an mRNA transcript

Question 14

5’ cap

Answer 14

important in binding of the ribosome

Question 15

tRNA (transfer RNA)

Answer 15

a form of RNA that is responsible for delivering amino acids to the ribosomes during the process of translation

Question 16

Exons

Answer 16

segments of DNA that code for part of a specific protein

Question 17

Introns

Answer 17

noncoding region of a gene

Question 18

Splicesomes

Answer 18

particles made of RNA and protein that cut introns from mRNA primary transcript and joins together the remaining coding exon regions

Question 19

Anticodon

Answer 19

group of three complementary bases on tRNA that recognizes and pairs with a codon on the mRNA

Question 20

Silent

Answer 20

substitution has no effect on which amino acid is being coded for

Question 21

Missense

Answer 21

substitution results in a different amino acid being coded for

Question 22

Frameshift

Answer 22

addition or deletion of a base pair causes a shift in the translation of a nucleotide sequence

Question 23

Nondisjunction

Answer 23

improper separation of homologous chromosomes during meiosis

Question 24

Deletion

Answer 24

loss of chromosomal material due to mispairing during mitosis/meiosis, and the subsequent “correction” by the cell’s repair enzymes

Question 25

Substitution

Answer 25

the replacement of one base in a DNA sequence by another base

Question 26

Translocation

Answer 26

movement of an entire segment of a chromosome to a new location on the same chromosome or to a different chromosome

Question 27

Inversion

Answer 27

flipping around of a sequence, back to front

Question 28

Insertion

Answer 28

the placement of an extra nucleotide in a DNA sequence

Question 29

Chain Termination

Answer 29

alteration results in a stop codon sequence

Question 30

Mutagen

Answer 30

any agent that increases the rate of mutation

Question 31

Ionizing Radiation

Answer 31

• damage is random and severe

- high energy creates free radicals from water molecules in cell

Question 32

UV Radiation

Answer 32

• lower energy radiation absorbed by nitrogenous bases of DNA
• introduces a kink in the DNA

Question 33

Chemical Mutagen

Answer 33

Involves direct mutation or chemical modifications of DNA bases

i) chemical looks like one of the DNA nucleotides and is incorporated into DNA, causing mispairing
ii) chemicals that remove amino group from bases adenine and cytosine, causing mispairing
iii) transportation
- foreign but of DNA is incorporated in middle of gene
- occurs in both prokaryotes and eukaryotes