DNADNA

Name the organelle and give its function.

Animal Plant

Nucleus

Ribosome

Endoplasmic Reticulum: aids in processing carbohydrates, lipids and proteins for export from the cell

Endoplasmic Reticulum

Golgi Body

Nucleus: control body of the cell; contains the genetic material (DNA)Golgi Aparatus: modifies, sorts, and packages materials from the ER for storage in the cell or secretion outside the cell

Ribosome: site where proteins are made

What is located in the nucleus?

What type of organic compound is DNA?

What is the monomer of DNA?

What does the DNA of all these organisms have in common?

They all share a universal genetic code.

The History of Heredity

Why am I so gorgeous?

Gregor Mendel

Gregor Mendel determined that traits were passed from generation to generation.

But, I haven’tfigured out

how thishappens

What was this substance called?

DNA

Rosalind Franklin &Maurice Wilkins

Franklin and Wilkins used x-ray to discover that DNA was a double helix.

Watson and CrickWatson & Crick won a Nobel Prize for discovering the structural model of DNA.

They credited Wilkins and Franklin. Wilkins also got a Nobel Prize but Franklin did not. Rosalind had passed away and the Nobels are not awarded posthumously.

Erwin Chargaff

Chargoff discovered that DNA contains the same amount of adenosine as thymine and the same amount of cytosine as guanine.

A A A

T T T C C

C C

G GG G

DNA is a Nucleic AcidWhat is a nucleic acid?

Nucleic acids are one of the major organic compounds.

Nucleic acids contain C, H, N, O, P

Are made up of nucleotide monomers

Double helix shape

Store genetic information

Help make proteins

Examples: DNA & RNA

sugar

phosphate

nitrogen base

A NUCLEOTIDE

H

H2

H H

H3

HH H

H

H

O

O

O

C C

C

N

N

PO

O

O

C

C

C C

C

O

OO

C

C

1.

2.

3.

1.

2.

3.

1. Phosphate Group2. 5-Carbon Sugar

(Dexoyribose or Ribose)3. Nitrogen Base

1. Phosphate Group

2. 5-Carbon Sugar(Dexoyribose or Ribose)

3. Nitrogen Base

Nucleotides, too

NucleotidesThere are four nitrogen bases making up four different nucleotides.

Adenine

Guanine

Thymine

CytosinePyrimidines

PurinesA

C

G

T

N base

Chargaff’s Base Pair Rules

Adenine always bonds with thymine. A = T

Guanine always bonds with Cytosine. G C

The lines between the bases represent hydrogen bonds

A

CG

T

C

G

A

A

T

G

Nucleotide

PS

N-b

Pairing DNA NucleotidesWhat is a nucleotide?

Rule

A to

C to

T

G

What is the base pairing rule?What would be the complementary nucleotide pairing?

3’End

3’End 5’End

5’End

DN

A D

OU

BL

E H

EL

IX

ladder shaped molecule

Purpose of DNA

Why do we have DNA?

For what does it code?

What actually makes you look the way you do?

Remember that the monomer for proteins

is amino acids!

DNA Codes for Amino Acids

The nitrogen bases in DNA code for amino acids.

A triplet of nitrogen bases codes for one amino acid.

The triplet is called a codon.

What is RNA?

DNA must have a “helper” molecule.

RNA stands for RiboNucleic Acid

RNA is a single stranded nucleic acid made up of monomers called nucleotides

sugar

phosphate

nitrogen base

A

B

C

RNA Nucleotides

A - Sugar (ribose)

B - Phosphate

C - Nitrogen base

sugar

phosphate

nitrogen base

Name the parts of the nucleotide.

Rules for Base Pairing

Cytosine pairs with Guanine

Adenine pairs with Uracil

Notice that RNA has Uracil (not thymine)

A = U

C = G

Rules for Base Pairing

C = G

A = U

3’ DNA strand

5’ DNA strandRNA strand

C

A

T

G

G

U

C

A

What is the function of RNA?

Carries DNA’s message code

Helps make protein

Types of RNAMessenger RNA (mRNA)Transfer RNA (tRNA)Ribosomal RNA (rRNA)

Phosphate Group

Nitrogen Base

Sugar

(ribose)

RNA

Identify the parts of the RNA strand.

DNA RNA

Sugar is deoxyribose

Sugar is ribose

Adenine base is present

Cytosine base is present

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√

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Comparing DNA & RNA

DNA RNA

Guanine base is present

Thymine base is present

Uracil base is present

Shape is double helix

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√

√

√

Comparing DNA & RNA

DNA RNA

Shape is single stranded

Located in nucleus

Located in cytoplasm

Stores genetic information

√

√ √

√

√

Comparing DNA & RNA

DNA RNA

Functions in protein synthesis

Composed of nucleotides

Template for synthesis of proteins

Transcribes the Template

More than one type

√ √

√ √

√

√

√

Comparing DNA & RNA