In your composition book, draw and fill

out this table, be sure to include today’s

date (1/11/18):

Replicate Definition(you write this)

The word in another language

Root of the word:

from Latin replicātiō

meaning (a folding

back)

ILLUSTRATE(Draw a picture

illustrating the word)

Use the word in asentence

● https://www.dnalc.org/resources/3d/03-mechanism-of-replication-basic.html

DNA & Replication

Headings

Vocabulary

Important Words

CHROMOSOME

CHROMATIN

DNA

NUCLEUS

Structure of DNA

(DeoxyriboNucleic Acid)

• Using critical info from the work of others (Rosalind Franklin & Linus Pauling)…

• James Watson & Francis Crick made 1st

model of DNA in 1953

• DNA is a Nucleic Acid(AKA: Organic Compound)

• DNA is made up of small subunits called: Nucleotides

DRAW THIS IN YOUR NOTES!“YES, THE ENTIRE PICTURE!!!”

Each nucleotide is made up of:

1. Deoxyribose (sugar)

2. Phosphate group (“P”)

3. Nitrogen Base (4 types)

•Adenine- A

•Thymine-T

•Cytosine- C

•Guanine-G

What Makes Up DNA?

Purine

Pyrimidine

Purine

Pyrimidine

Sugar =

Ends in

-ose

•2 long chains of nucleotides

•Joined together in the form of a ladder

•Ladder is twisted in the form of a double helix or spiral

What Is the “Ladder”?

Hydrogen

bonds

Nucleotide

Sugar-phosphate

backbone

Key

Adenine (A)

Thymine (T)

Cytosine (C)

Guanine (G)

Structure of DNA

•Sides of the Ladder =

•Alternating Deoxyribose(Sugar) & Phosphate

•s-P-s-P-s-P-etc.

•Rungs or Steps of ladder =

•Pairs of Nitrogen Bases

•A-T or C-G

•T-A or G-C

•Adenine(A) pairs up w/ Thymine(T)

•Guanine(G) pairs up w/ Cytosine(C)

Example:

A G C T A C G C A 5’

T C G A T G C G T3’

How Do Nitrogen Bases Pair Up?

3’

5’

•All organisms have the same type of nucleotides

•Nucleotide arrangement provides for all the different types of organisms

Ex: A mouse and a rosebush have the same nucleotides…but…

Different Nucleotide Order = Different Organism!!!

*This sequence of nucleotides = GENETIC CODE

Why Do Organisms Look So Different?

Replication of DNA•During cell division a copy of DNA must be made

•When new cells are formed each new cell gets an exact copy of the genetic information.

•This copy of DNAis made through a process known as Replication.

Let’s see DNA Replication at Work!

Steps of Replication•During replication, each strand serves as a pattern to make new DNA molecule.

1. The 2 nucleotide strands separate at base pairs.

• They unzip like a zipper using DNA Helicase (enzyme)

2. Each strand then builds its opposite strand by base pairing with nucleotides that float freely in the nucleus.

3. Each new DNA molecule has 1 nucleotide strand from the original DNA molecule and 1 nucleotide strand made from free nucleotides in the nucleus.

DNA Replication

Growth

Growth

Replication

fork

DNA polymerase

New strand

Original

strand DNA

polymerase

Nitrogenous

bases

Replication

fork

Original

strand

New strand