Overview of Genome Transmission and Expression

Question 1

What is DNA known for?

Answer 1

information

Question 2

What is RNA known for?

Answer 2

decoding

Question 3

What is protein known for?

Answer 3

work

Question 4

What genetic information do cells have?

Answer 4

DNA and RNA

Question 5

What genetic information do viruses have?

Answer 5

RNA

Question 6

At what length does replication occur?

Answer 6

the entire DNA sequence

Question 7

At what length does transcription occur?

Answer 7

snippet of DNA sequence

Question 8

What is the flow of genetic information?

Answer 8

unidirectional

Question 9

What is the function of DNA?

Answer 9

physically stores genetic information in a stable, heritable form

Question 10

What four nucleotides make up DNA?

Answer 10

guanine, adenosine. thymidine, cytosine

Question 11

What carries the information “code”?

Answer 11

the linear sequence of nucleotides in DNA

Question 12

What are the base pairs in a double helix?

Answer 12

A pairs with T and C pairs with G

Question 13

What is the direction of each strand of DNA?

Answer 13

directional or asymmetric - the two strands are anti-parallel to each other

Question 14

How is DNA replicated for transmission?

Answer 14

1. original strands are separated
2. new DNA strands are synthesized in an anti-parallel manner by DNA polymerase using the old strands as templates
3. nucleotides are added in a complementary manner
4. two identical double-stranded DNA molecules from one original molecule
5. all cellular sequences in an organism comprise its genome

Question 15

How is one single strand DNA a backup?

Answer 15

a single strand can act as a template for a double strand

Question 16

What helps chromosomes to segregate accurately?

Answer 16

copied chromosomes are held together prior to separation

Question 17

What is the transmission of the genome?

Answer 17

1. replication: accurate copying of information
2. segregation: correct separation of copies
3. transfer of copies into new cells created by division of the original cell

Question 18

What follows each step of cell division?

Answer 18

safety net and checkpoints

Question 19

What must be expressed before genetic information is stored in the genome?

Answer 19

transcription

Question 20

What is transcription?

Answer 20

copying of a segment of DNA into RNA

Question 21

What happens after transcription?

Answer 21

RNA is either used directly by the cell or used as an information template to direct synthesis of a particular protein (translation)

Question 22

What is special about RNA?

Answer 22

can act as a storage molecule and synthesize proteins on its own (catalysis; w/o protein)

Question 23

How does RNA polymerase work?

Answer 23

uses one strand of DNA as a template to synthesize a complementary RNA strand

Question 24

What is the difference between RNA and DNA?

Answer 24

RNA contains uracil instead of thymine

Question 25

What initiates transcription?

Answer 25

specific DNA sequences instruct RNA polymerase where to start and to stop transcribing

Question 26

What is the primary transcript?

Answer 26

the RNA produced immediately after transcription, which is processed into the final RNA product

Question 27

What are the three types of RNAs?

Answer 27

1. mRNA 2. tRNA 3. rRNA

Question 28

What is the function of mRNA?

Answer 28

carries the sequence encoding a protein and acts as the template for translation

Question 29

What is the function of tRNA?

Answer 29

acts as an adapter that "reads" the mRNA and brings the encoded amino acids for protein synthesis

Question 30

How long are tRNAs?

Answer 30

80-100 nucleotides in length

Question 31

What is the function of rRNA?

Answer 31

together with ~100 proteins form ribosomes, which are protein synthesis factories where translation occurs

Question 32

How are nucleotides read?

Answer 32

3 nucleotides/ protein

Question 33

What is translated into proteins?

Answer 33

mRNA

Question 34

How do proteins have potential for variation in structure and function?

Answer 34

proteins are synthesized from 20 different amino acids

Question 35

What is function of proteins?

Answer 35

carry out most cellular function (e.g. structural and catalytic)

Question 36

What are the characteristics of proteins?

Answer 36

1. can range from a few amino acids long (e.g. calmodulin) to many thousands (e.g. hemagglutinin)-typically between 100-1000 amino acids in lengths 2. may contain distinct separate proteins that come together to form a functional unit (e.g. hemagglutinin)

Question 37

What translations the mRNA?

Answer 37

tRNA and rRNA

Question 38

What is translation?

Answer 38

turns the information from an mRNA into a protein

Question 39

What is a codon?

Answer 39

triplets of nucleotides in the mRNA that encode each amino acid

Question 40

What initiates and terminates translation?

Answer 40

distinct sequences in the mRNA

Question 41

What order does tRNA decode?

Answer 41

recognizes each codon in order from 5' to 3'

Question 42

Where does translation occur?

Answer 42

translation is performed by the ribosome, which is composed of rRNAs and proteins

Question 43

What is the cellular structure of prokaryotes?

Answer 43

do not have internal membrane-bound compartments (e.g. the nucleus)

Question 44

Where is DNA located in prokaryotes?

Answer 44

in the nucleoid

Question 45

T or F: transcription and translation can occur simultaneously in prokaryotes

Answer 45

true

Question 46

What is cellular structure of eukaryotes?

Answer 46

contain several membrane-bound organelles (e.g. the nucleus, mitochondria, chloroplasts)

Question 47

Where is DNA located eukaryotes?

Answer 47

in the nucleus

Question 48

Where does replication and transcription occur in eukaryotes?

Answer 48

in the nucleus

Question 49

Where does translation occur in eukaryotes?

Answer 49

translation occurs in the cytoplasm within ribosomes so mRNA must be exported to cytoplasm for translation

Question 50

T or F: transcription and translation can occur simultaneously in eukaryotes?

Answer 50

false