unit 4 concept 2

Question 1

Protein Synthesis

Answer 1

the process of reading the instructions in DNA to make a polypeptide

Question 2

Polypeptide

Answer 2

a chain of amino acids

Question 3

Polypeptide can bind

Answer 3

Can bind to others and fold into a protein (4 levels)

Question 4

DNA

Answer 4

instructions, located in the nucleus (which it cant leave)

Question 5

proteins are made in

Answer 5

ribosomes (located outside the nucleus in the cytoplasm)

Question 6

protein synthesis takes 2 steps

Answer 6

Transcription
Translation

Question 7

DNA —> RNA —-> Protein

Answer 7

DNA->RNA is through transcription

RNA–> is through translation

Question 8

Three essential types of RNA

Answer 8

tRNA mRNA and rRNA

Question 9

mRNA (messenger)

Answer 9

copies instructions in DNA and carries these to the ribosomes in the cytoplasm

Question 10

tRNA (transfer)

Answer 10

binds and carries specific amino acids to the ribosome

Question 11

rRNA (ribosomal) (2)

Answer 11

along with proteins, make up the ribosome
- they also help catalyze the formation of peptide bonds

Question 12

Location of transcription

Answer 12

nucleus

Question 13

Transcription DNA -> mRNA
Purpose

Answer 13

carry the code/instructions out of the nucleus
- (DNA never leaves the nucleus, and proteins are made in the cytoplasm by ribosomes)

Question 14

transcription Starts with:

Answer 14

DNA

Question 15

transcription ends with

Answer 15

mRNA (can/will leave the nucleus)

Question 16

Process of trasncription

Answer 16

1. RNA polymerase binds to the DNA promoter where transcription is to begin and unzips the gene that needs to be copied
   - Looks for the TATA box as a signal
2. RNA polymerase uses complementary base pairing rules to match RNA nucleotides with the exposed DNA nucleotides
   - A=U and G=C
3. Releases the completed mRNA molecule.
4. DNA zips back up and the mRNA leaves the nucleus and enters the cytoplasm

Question 17

Transcription definition

Answer 17

DNA is copied into a complementary strand of mRNA

Question 18

RNA is made in the

Answer 18

5’ -> 3’ direction

Question 19

The DNA template is read in the

Answer 19

3’->5’ direction’

Question 20

mRNA is read in groups of

Answer 20

3, always starts with AUG

Question 21

Post-Transcription Modifications

Answer 21

RNA splicing (to join or connect)

Question 22

mRNA has i

Answer 22

introns (non-coding regions) and exons (coding regions)

Question 23

5’ cap

Answer 23

(G cap, a modified guanine) is added to the 5’ end
Facilitate mRNA’s bonding to a ribosome for translation

Question 24

Poly A tail

Answer 24

(50-250 A’s) is added to the 3’ end
- Helps the mRNA leave the nucleus

Question 25

Genetic code

Answer 25

code of instructions for how to make protein

Question 26

Codon

Answer 26

a set of 3 nucleotides on the mRNA

Question 27

Anticodon

Answer 27

“complementary” 3 nucleotides on tRNA

Question 28

Amino acid is the

Answer 28

monomer (building block for making proteins, held together by peptide bonds)

Question 29

Translation starts with and ends with

Answer 29

mRNA -> polypeptide

Question 30

Purpose of translation

Answer 30

read/follow the instructions carried on the mRNA to make a polypeptide

Question 31

Location of translation

Answer 31

ribosomes in the cytoplasm

Question 32

translation process 4

Answer 32

1. mRNA attaches to the small subunit of the ribosome 2. Ribosome reads the mRNA codons, always in the 5’ -> 3’ direction, starting at the AUG codon. - 1 codon = 3 RNA nucleotides 3. tRNAs act like taxis to pick up and drop off the amino acids that match with each codon. 4. tRNAs continue to drop off a.a. and the a.a binds the amino acids together with peptide chain

Question 33

Translation

Answer 33

interpretating the RNA message into a polypeptide to make a protein

Question 34

Summary of process

Answer 34

draw it out

Question 35

Regulation

Answer 35

- gene expression is a highly regulated process

Question 36

regulation can

Answer 36

turn genes “on” and “off” is critical for cell differentiation

Question 37

reguluation can happen

Answer 37

- can happen before, during, or after transcription or translation

Question 38

- transcription factors

Answer 38

regulatory PROTEINS that control gene activity - repressors decrease transcription - activators increase transcription

Question 39

example of regulator inhibitor

Answer 39

- HIV is an example of a virus that disrupts regulation

Question 40

Epigenetics

Answer 40

- The study of changes in gene expression that are heritable

Question 41

epigenetics is different from

Answer 41

- Mutation: a change in DNA sequence - Epigenetics: DO NOT EFFECT the actual DNA sequence, just how the DNA sequence gets expressed - Eg. histone modification