chapter 7

Question 1

What are the two types of nucleic acid?

Answer 1

DNA and RNA

Question 2

What are the 3 prime (3’) ends?

Answer 2

the end of a nucleic acid strand terminating at the third carbon of a sugar molecule

Question 3

What are the 5 prime (5’) ends?

Answer 3

the end of a nucleic acid strand terminating at the fifth carbon of a sugar molecule

Question 4

Which bases in DNA and RNA are complimentary?

Answer 4

DNA: A-T, C-G
RNA: A-U, C-G

Question 5

Which bases are purines and pyrimidines

Answer 5

Purines: A and G
Pyrimidines: C and T

Question 6

what is the structural significance of these bases?

Answer 6

purines: two rings
pyrimidines: one ring

Question 7

What type of bond holds complementary bases together?

Answer 7

hydrogen bond

Question 8

What is an organism’s genome?

Answer 8

all the genes an organism possesses

Question 9

What are chromosomes

Answer 9

a DNA molecule wrapped around proteins

Question 10

what are genes

Answer 10

a sequence of DNA

Question 11

What is the “central dogma” of biology?

Answer 11

DNA-RNA-Protein

Question 12

What are transcription and translation?

Answer 12

Transcription: DNA-RNA
Translation: RNA-Proteins

Question 13

Where do these processes occur in eukaryotic cells?

Answer 13

Transcription: nucleus
Translation: ribosomes

Question 14

what is the difference between DNA and RNA in terms of their sugar

Answer 14

Deoxyribose sugar in dna
ribose in rna

Question 15

what is the difference between DNA and RNA in terms of their nucleotide bases

Answer 15

DNA has thymine
RNA has Uracil

Question 16

what is the difference between DNA and RNA in terms of their form

Answer 16

DNA is double stranded
RNA generally single stranded

Question 17

what is the difference between DNA and RNA in terms of their functions.

Answer 17

DNA: stores RNA
RNA: Makes Proteins

Question 18

What are the three types of RNA involved in the synthesis of proteins, and what are their specific functions?

Answer 18

mRNA: Messenger RNA= Delivers a copy to ribosomes
rRNA: Ribosomal RNA= makes up ribosomes
tRNA: transport RNA= delivers amino acids

Question 19

What are the three steps of transcription?

Answer 19

initiation, elongation, and
termination

Question 20

What generally occurs during initiation

Answer 20

RNA polymerase binds to and unzips DNA

Question 21

What generally occurs during elongation

Answer 21

RNA polymerase reads the DNA strand and adds complementary nucleotides.

Question 22

What generally occurs during termination

Answer 22

RNA polymerase detaches from the DNA and releases RNA strand

Question 23

What are the functions
of RNA polymerase?

Answer 23

opens double helix and dna can be copied into the language of RNA

Question 24

What are the template strand

Answer 24

the strands that transcribed

Question 25

What are the promoter

Answer 25

where transcription begins

Question 26

What are the template terminator?

Answer 26

where transcription ends

Question 27

What are the cap and tail?

Answer 27

The group at the beginning (5' end) is called a cap, while the group at the end (3' end) is called a tail.

Question 28

What are two functions of the 5’ cap and 3’ poly-A tail?

Answer 28

They protect mRNA and help ribosomes attach to proteins

Question 29

What are introns and exons, and which is removed before translation?

Answer 29

introns: noncoding regions (removed) Exons: coding regions

Question 30

what are the genetic code

Answer 30

the way cells read rna to know what protein to assemble

Question 31

codons?

Answer 31

a triplet of mRNA bases that specifies a particular amino acid or a “stop” signal

Question 32

What are the three steps of translation? And what happens?

Answer 32

initiation: translation begins elongation: Ribosomes move along mRNA attaching amino acids to polypeptides and termination: Comes to a stop

Question 33

what is gene regulation

Answer 33

How to control the expression of genes

Question 34

what is an operon

Answer 34

group of genes that controls the transcription of the entire group of genes

Question 35

what are the operator and repressor

Answer 35

operator: the on-off switch repressor: blocks transcription

Question 36

What is the function of lac operon?

Answer 36

it breaks down lactose by making enzymes

Question 37

In the absence of lactose, does transcription of genes occur?

Answer 37

no

Question 38

In the presence of lactose, does transcription of genes in the operon occur?

Answer 38

yes

Question 39

What is the purpose of the proteins produced?

Answer 39

to break down lactose if its available