“Central Dogma” & Date

Main Ideas/Lectu

re Topics

“Big Ideas” or Chunking the

Lecture

DNA(polymer)

mRNA (polymer)

Protein* (polymer)

*Made from amino acids (monomers)

The Central Dogma: “Getting the Information Out”

2) Transcription 3) Translation

1) Replication

DNA

3

2

1Replication

Transcription

Translation

RNA DNASugar Ribose Deoxyribose

Phosphate

Yes Yes

Bases AUGC ATGC

Length Short Long

Strands Single Double

1 DNA Replication

Figure 2

Nuclear Membrane

DNA Replication• Happens during

“interphase” (just before Meiosis & Mitosis)

• Creates a second, complementary set of (23 or 46) chromosomes for cell about to be created

Goes to

new cell

Goes to old

cell

DNA(polymer)

mRNA (polymer)

Protein* (polymer)

*Made from amino acids (monomers)

The Central Dogma: “Getting the Information Out”

2) Transcription 3) Translation

1) Replication

DNA

Process #1: DNA Replication Molecule(s) involved: DNA

Steps taken:1. The DNA double-helix opens up (“unzips”).2. Free-floating nucleotides line up with their

correct partner nucleotides on the DNA strand.3. Free-floating nucleotides physically connect

(bond) to the DNA strand.4. A new strand of DNA is formed along each of

the open strands.5. Two complete and identical DNA helices are

created.6. Cell division can now occur with the newly

created DNA strand.

Base Pairing Rules:DNA DNA

DNA:DNA:

Parent strandDaughter strand

Adenine (A)

Thymine (T)

Guanine (G)

Cytosine (C)

Thymine (T) Adenine (A) Cytosine (C) Guanine (G)

DNA(polymer)

mRNA (polymer)

Protein* (polymer)

*Made from amino acids (monomers)

The Central Dogma: “Getting the Information Out”

2) Transcription 3) Translation

1) Replication

DNA

Process # 2: Transcription Molecule(s) involved: DNA, mRNA Steps taken:

1. A small section of DNA is opened up.2. One DNA strand acts as a template and

guides how the mRNA is to be made.3. The mRNA is built of new nucleotides, similar

to how DNA is built.4. As the mRNA is made, it separates from the

DNA template.5. When the entire gene (DNA segment) is

copied (into the form of mRNA), the DNA completely releases the mRNA.

Base Pairing Rules:DNA mRNA

DNA:mRNA:

Adenine (A)

Thymine (T)

Guanine (G)

Cytosine (C)

Uracil (U) Adenine (A) Cytosine (C) Guanine (G)

DNA(polymer)

mRNA (polymer)

Protein* (polymer)

*Made from amino acids (monomers)

The Central Dogma: “Getting the Information Out”

2) Transcription 3) Translation

1) Replication

DNA

3

Translation

Process #3: Translation

Molecule(s) involved: DNA, mRNA

Steps taken:

1) mRNA strand connects to the ribosome.2) First tRNA’s anticodon docks with the mRNA’s start codon.

(AUG (and always brings the amino acid methionine (met))3) Second tRNA “docks” with ribosome & mRNA strand.4) Amino acid from #2 tRNA attaches to amino acid from #1. 5) First tRNA leaves.6) Whole assembly moves forward one codon (3 letters).7) Repeat process until mRNA’s “stop” codon is reached.

(UAG, UAA, or UGA)8) A release factor breaks up the party.

Base Pairing Rules:mRNA tRNA

mRNA:tRNA:

Adenine (A) Uracil (U) Guanine

(G) Cytosine

(C)

Uracil (U) Adenine (A) Cytosine (C) Guanine (G)

mRNA nucleotid

es

Amino Acid (1 of

20)

3 nucleotides (“codon”) = 1 amino acid

mRNA nucleotid

es

Amino Acid (1 of

20)

3 nucleotides (“codon”) = 1 amino acid

Translation

Figure 2

mRNA

tRNA

rRNA

DNA mRNA tRNA ProteinLocation(s): Nucleus Nucleus

CytoplasmCytoplasm Cytoplasm

Sugar Deoxyribose

Ribose Ribose NA

Phosphate Yes Yes Yes NA

Chemical Bases

ATCG AUCG AUCG NA

Processes Involved

Replication, Transcriptio

n

Transcription,Translation

Translation Translation

Interacts with Amino

Acids

No No Yes Yes

Structure Double Stranded

Single Stranded

Triplet “Codon”

Single Stranded

“Handedness”

Left Right Left NA

Purpose Master blueprint of

cell activities

Create new proteins:

carry copy of DNA

message to ribosome

Create new proteins:

Carry amino acid to

ribosome

Serve as structural parts of

body and/or enzymes