Biol-M 200 Lecture 7

Front 1

What are genes?

Back 1

unit of inheritance that determine the traits (characteristics) passed from one generation to the next

Front 2

What are alleles?

Back 2

Variants of a gene

Ex: genes that determine pea pod shape

Front 3

What is a genome?

Back 3

The entire collection of all genetic material in a microbe

Front 4

2 DNA strands intertwine to form a ______ _____.

Back 4

Double Helix

-each strand is complimentary & anti-parallel

Front 5

A always binds to ____ in DNA.

C always binds to ____ in DNA.

Back 5

A - T

C - G

Front 6

What is Chargaff's Rule?

Back 6

%A = %T

%G = %C

Front 7

Where does DNA carry the genetic information?

Back 7

In its sequence

Front 8

Where do eukaryotic cells keep chromosomes?

Back 8

Condensed & packaged into the NUCLEUS

Front 9

What kind of chromosomes do prokaryotes have?

Back 9

Single, circular chromosomes

Front 10

What are plasmids?

Back 10

- Small circular extra-chromosomal DNA

- Carries genes with non-essential functions (antibiotic resistance)

(not part of the chromosome)

Front 11

What is the central dogma of biology?

Back 11

DNA (Genes) --> RNA (Messages) --> Protein (Products)

Front 12

What is replication?

Back 12

DNA copying itself

Front 13

What is transcription?

Back 13

DNA making RNA

Front 14

What is translation?

Back 14

RNA making protein

Front 15

What is semiconservative replication?

Back 15

Each strand serves as a template for replication

Front 16

What does a helicase do?

Back 16

"unzips" DNA

(replication fork forms)

Front 17

What is DNA polymerase (DNAP)?

Back 17

the replicating enzyme

Front 18

DNA synthesis occurs ___' to ___'

Back 18

5' to 3'

Front 19

2 types of strands formed during replication?

Back 19

Lagging & Leading

Front 20

What direction does DNAP move?

Back 20

towards the helicase

Front 21

Which strand is fragmented because it has to go back every time DNA is unzipped?

Back 21

the lagging strand

Front 22

What is the origin (oriC)?

Back 22

A specific DNA sequence at which replication begins

Front 23

What is the terminus (terC)?

Back 23

A DNA region at which each replication fork ends during replication

Front 24

How does replication initiate?

Back 24

DNA polymerase and helicase bind to DNA at oriC and begin replication

Front 25

Replication is _____________?

Back 25

Bidirectional: two complexes of DNA polymerase set off in opposite directions

(greek letter theta)

(also called "Theta" replication"

Front 26

Where do both copies of replicated DNA reside after separation?

Back 26

in its own new daughter cell

Front 27

Describe RNA synthesis (transcription)

Back 27

1. DNA sends messages to ribosomes

2. mRNA message is made by RNA polymerase

3. Promoters control transcription

Front 28

________+_______= RNA polymerase

Back 28

Core + Sigma

Front 29

What is the core responsible for?

Back 29

assembling RNA

Front 30

What is sigma responsible for?

Back 30

- Finding promoters on the DNA strands where the RNA polymerase can bind

- each sigma recognizes a specific promoter sequence & determines which messages get sent

Front 31

What are promoters?

Back 31

DNA sequences that indicate where to start transcription (start the message)

Front 32

What 2 things are part of a promoter?

Back 32

-35 box & -10 box

Front 33

Promoter sequences are NOT ______?

Back 33

identical

Front 34

How do you determine the consensus sequence for "sigma"?

Back 34

average all the promoter sequences

Front 35

What do promoters vary in?

Back 35

strength-which is determined by consensus

Front 36

Stronger promoters are closer to _________.

Back 36

consensus

Front 37

What are 2 things strong promoters do?

Back 37

- call over lots of RNA polymerases

- microorganism will create lots of messages

(lots messages= lots of protein later on)

Front 38

What does RNA polymerase unwind a small piece of DNA into?

Back 38

single strands

Front 39

What will nucleotides base pair with?

Back 39

the complementary DNA

Front 40

What does RNA polymerase do?

Back 40

polymerizes RNA, duh.

Front 41

What is RNA transcript complementary to?

Back 41

DNA template strand

Front 42

What does RNA polymerase use one strand of as a template?

Back 42

DNA

Front 43

What does rRNA (ribosomal) do?

Back 43

forms structure of the ribosome, recognizes messages, assembles proteins

Front 44

_____ is central to protein synthesis.

Back 44

RNA

Front 45

What does tRNA (transfer)?

Back 45

activates amino acids and reads the mRNA message

Front 46

What does mRNA (messenger) do?

Back 46

carries the message from the DNA (gene)

Front 47

Protein synthesis= __________

Back 47

Translation

Front 48

What is a protein's shape/function determined by?

Back 48

its primary sequence of amino acids

Front 49

How many different amino acids are there?

Back 49

20

Front 50

Protein + rRNA --> Prokaryotic 70S

Back 50

30S + 50S

(smaller than eukaryotic and shaped differently)

Front 51

Protein + rRNA --> Eukaryotic 80S

Back 51

40S + 60S

Front 52

There is one unique mRNA strand for each unique _______.

Back 52

protein

Front 53

A cell can make multiple copies of the same protein from one ________.

Back 53

mRNA

Front 54

Each amino acid matches a unique tRNA with what a specif ____________ _____________?

Back 54

nucleotide sequence

Front 55

During translation initiation, the ribosome assembles on the mRNA at a specific spot called the ____________.

Back 55

shine-dalgarno sequence

Front 56

During translation initiation, where do activated tRNA's arrive?

Back 56

at the ribosome

Front 57

During translation elongation, a peptide bond is formed between what?

Back 57

the two amino acids

Front 58

During translation elongation, how many nucleotides does the ribosome slide down the mRNA?

Back 58

three nucleotides

Front 59

During translation elongation, what is formed when NEW activated tRNA arrives?

Back 59

ribosome forms another peptide bond

(the cycle repeats)

Front 60

During translation elongation, protein is syntheiszed from _________ to _________ as the cycle repeats.

Back 60

N-terminus to C-terminus

Front 61

During translation termination, a mRNA sequence called a ______ _______ terminates protein syntheis.

Back 61

stop codon

Front 62

During translation termination, what happens to the protein and the ribosome?

Back 62

-the protein is RELEASED

-the ribosome DISASSEMBLES

Front 63

What is the translation start site?

Back 63

the message starts 6-9 bases in the 3' direction of the SHINE-DALGARNO SEQUENCE

Front 64

What is the specific start site?

Back 64

a CODON: AUG

Front 65

What is always the first amino acid in translation?

Back 65

Methionine (Met)

Front 66

What is a codon?

Back 66

a series of three nucleotides

Front 67

How is a particular amino acid specified?

Back 67

By recruiting the appropriate tRNA

Front 68

A start codon sets the ________ which determines all subsequent codons.

Back 68

frame

Front 69

After each peptide bond is formed, the ribosome slides ____ bases down the mRNA strand.

Back 69

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