Unit C Topic 3 - The Central Dogma of Biology

Question 1

Erwin Chargaff

Answer 1

A+T and C+G are in equal amounts in DNA (Paired)

Question 2

Alfred Hershey and Martha Chase

Answer 2

Used radioactive labling to discover that DNA is heritable molecule passed between bacteria

Question 3

Rosalind Franklin

Answer 3

Used X-rays and discovered DNA is a helix

Question 4

James Watson and Francis Crick

Answer 4

Porduced the first sturctural model of DNA

Question 5

What does DNA stand for

Answer 5

Deoxyribonucleic acid

Question 6

Nucleotides structure

Answer 6

5 - carbon sugar, a phosphate group and a ring shaped nitrogen base (A T G C)

Question 7

PUR As Gold

Purine nucleotides

Answer 7

Adenine and Guanine (double ringed structure)

Question 8

CuT the PY

Pyrimidine nucleotides

Answer 8

Thymine and Cytosine (single ringed)

Question 9

Structure of DNA

shape, structure, bonds

Answer 9

• Double helix
• two antiparalel strands of nucleotides
• nucleotide strands linked together by a sugar-phosphate backbone
• Nucleotide pairs linked by hydorgen bonds

Question 10

Endosymbiosis Theory

Answer 10

Mitochondira and chloroplasts were once self-sustaining organisms

Question 11

Where do you inherit Mitochondiral DNA from?

Answer 11

From your Mother

Question 12

H T R D3 D1 L

DNA Replication steps

Answer 12

1. Helicase unzips double helix
2. Topoismerase prevents supercoiling
3. RNA Primase moves along (3’-5’) and adds RNA primer (5’-3’)
4. DNA Polymerase III begins at primer moves along the DNA 3’-5’ adding new DNA and adding more DNA 5’-3’
5. DNA Polymerase I Replaces RNA primer with DNA
6. Ligase seals the backbones

Question 13

Leading strand

Answer 13

3’-5’, enzymes move toward replication fork

Question 14

Lagging strand

Answer 14

5’-3’, enzymes move away from replication fork (makes gaps or Okazaki Fragments)

Question 15

Semi-conservative relication

Answer 15

Each double-stranded DNA consists of one old parent strand and one newly produced strand

Question 16

How accurate is DNA replication?

And why

Answer 16

Very accurate because the enzymes proofread the new DNA to look for and correct errors

Question 17

The Central Dogma of Biology

Answer 17

DNA is transcribed into mRNA, which is translated into protiens

Question 18

Transcription

Answer 18

Making an RNA copy of a gene in DNA

Question 19

Translation

Answer 19

Using RNA code to create an amino acid sequence in a protein

Question 20

what does RNA stand for?

Answer 20

Ribonucleic acid

Question 21

How is RNA different than DNA?

Answer 21

• ribose sugar instead of doxyribose
• Uracil (U) replaces Thymine (T)
• single stranded and shorter

Question 22

Messanger RNA (mRNA)

Answer 22

RNA produced during transcription, containing the instructions to produce a protein

Question 23

Transcription steps

Answer 23

1. RNA polymerase locates a promoter sequence and unzips the DNA
2. Uses DNA template strand (moving 3
   3’-5’) to make complementary mRNA strand (moving 5’-3’)
3. RNA Polymerase reaches terminator sequence

Question 24

Coding strand

Answer 24

non-template strand in transcription

Question 25

Template strand

Answer 25

The strand of DNA the RNA polymerase uses to make the mRNA

Question 26

Promoter sequence

Answer 26

*Promotes* the production of mRNA (active site for RNA polymerase)

Question 27

Terminator sequence

Answer 27

Terminates the production of mRNA (unbinds RNA polymerase)

Question 28

mRNA Post-Transcriptional Processing steps

Answer 28

1. add 5' cap and a poly-A tail to mRNA to prevent degration 2. Spliceosomes splice RNA to code for proper protiens

Question 29

Exons

Answer 29

"expressed" sections that are kept in mRNA to code for proteins

Question 30

Introns

Answer 30

"interupting" sections of mRNA that are spliced out

Question 31

Mutations

Answer 31

A permanent change in genetic material that is bassed down to the daughter cells

Question 31

Point Mutation

Answer 31

mutation of just one nucleotide (Silent, Missense, nonsense)

Question 32

# Sh! Silent Mutation

Answer 32

mutations the doesn't change the amino acid

Question 33

# Missed it! Missense Mutation

Answer 33

Mutation that changes and amino acid

Question 34

# No! Nonsense Mutation

Answer 34

mutation that introduces an early stop codon

Question 35

Frameshift mutation

Answer 35

insertion/deletion mutation that shifts the reading frame of the whole DNA sequence, changing every amino acid made so far

Question 36

Translocation Mutation

Answer 36

Moving a section of DNA to a different location in the genome

Question 37

Inversion Mutation

Answer 37

Turning a section of DNA around (**3'-5'** to **5'-3'**)

Question 38

# (Enzymatic scissors) Restriction Enzymes

Answer 38

Cutting DNA at specific sites, staggered and leaving the **sticky ends** open to make it easier for the fragmented DNA to be re-integrated later | used in genetic engineering

Question 39

# Molecular Glue DNA Ligase

Answer 39

enzyme that joins strands of DNA together, allowing the DNA fragment (cut by restriction enzymes) to be added to a different DNA strand | Used in genetic engineering