TOOTHPICK BRIDGE TOOTHPICK BRIDGE CHALLENGE:CHALLENGE:

Using glue and toothpicks Using glue and toothpicks ONLY build a bridge that ONLY build a bridge that will support the most will support the most weight!weight!

Weight will be applied by Weight will be applied by attaching two hooks and attaching two hooks and suspending in from the suspending in from the midpoint of the bridge.midpoint of the bridge.

TOOTHPICK BRIDGE TOOTHPICK BRIDGE CHALLENGE:CHALLENGE:

Bridges will be tested in Bridges will be tested in 24 hours24 hours

You have 20 minutes to You have 20 minutes to complete your taskcomplete your task

Winning group receives Winning group receives candy!candy!

TOOTHPICK BRIDGE TOOTHPICK BRIDGE CHALLENGE:CHALLENGE:

What role did structure What role did structure play in the amount of play in the amount of weight that a toothpick weight that a toothpick bridge can support?bridge can support?

Structure plays a role in Structure plays a role in supporting life, too…supporting life, too…

DNA & GenesDNA & Genes

Lecture #1 Lecture #1

(12.1)(12.1)

I. WHAT DOES DNA LOOK I. WHAT DOES DNA LOOK LIKE?LIKE?

A. DNA is made up of a long A. DNA is made up of a long chain of _________________.chain of _________________.

1. 1. NucleotideNucleotide- Subunit of - Subunit of DNADNA

a. 1 Simple Sugar a. 1 Simple Sugar (dioxyribose)(dioxyribose)

b. 1 Phosphate Groupb. 1 Phosphate Group

c. 1 _____________________c. 1 _____________________

A Free NucleotideA Free Nucleotide

Phosphate

sugar

Guanine(Nitrogen Base)

B. Nitrogen B. Nitrogen BasesBases

1. Adenine (A)1. Adenine (A)

2. _______ (T)2. _______ (T)

3. _______ (C)3. _______ (C)

4. Guanine (G) 4. Guanine (G)

I. WHAT DOES DNA LOOK I. WHAT DOES DNA LOOK LIKE?LIKE?

Always Pair Up

Always Pair Up

I. WHAT DOES DNA LOOK I. WHAT DOES DNA LOOK LIKE?LIKE?

DNA PICTUREDNA PICTURE The side is The side is

made of made of ________ & ________ & phosphatephosphate

Nitrogen bases Nitrogen bases bonded in the bonded in the middle by a middle by a ________ bond________ bond

I. WHAT DOES DNA LOOK I. WHAT DOES DNA LOOK LIKE?LIKE?

C. __________________ ModelC. __________________ Model

1. Proposed by Francis Crick 1. Proposed by Francis Crick & James Watson in 1954& James Watson in 1954

2. Means: 2 sided stand, 2. Means: 2 sided stand, twistedtwisted

3. Looks like a ______________3. Looks like a ______________

II. WHAT IS DNA?II. WHAT IS DNA?A. DNAA. DNA1. Short for 1. Short for “deoxyribonucleic acid”“deoxyribonucleic acid”2. The genetic code that 2. The genetic code that contains instructions to contains instructions to build _________ build _________

____________________________________________________

II. WHAT IS DNA (cont.)II. WHAT IS DNA (cont.)B. Proteins- Polymer that provides B. Proteins- Polymer that provides structure for _______ and ________structure for _______ and ________

1. Different proteins cause 1. Different proteins cause different traits to appeardifferent traits to appear

C. Enzymes- Specialized proteins C. Enzymes- Specialized proteins responsible for chemical responsible for chemical reactions reactions 1. Necessary for 1. Necessary for ______, _______, ______, _______, _________, etc_________, etc

III. NUCLEOTIDE III. NUCLEOTIDE SEQUENCESEQUENCE

A. The order of the nitrogen A. The order of the nitrogen bases determines what bases determines what ________________________

B. The more alike the nucleotide B. The more alike the nucleotide sequence, the more closely sequence, the more closely related the ____________ related the ____________

1. Provides evidence of 1. Provides evidence of evolution evolution

IV. DNA ReplicationIV. DNA Replication

A. Before a cell can enter A. Before a cell can enter ______ or _______ it must ______ or _______ it must duplicate its DNA so that duplicate its DNA so that each daughter cell will get each daughter cell will get its share of DNA.its share of DNA.

B. B. DNA ReplicationDNA Replication- Making - Making an exact copy of DNA.an exact copy of DNA.

IV. DNA Replication (cont)IV. DNA Replication (cont)1. Separation of Strands1. Separation of Strands

a. An ______ splits the a. An ______ splits the nucleotide nucleotide pairs (unzips the pairs (unzips the zipper)zipper)

b. The bases are ___________ b. The bases are ___________

2. Base Pairing2. Base Pairing

a. Free nucleotide bases pair a. Free nucleotide bases pair up with up with the ___________ exposed the ___________ exposed basesbases

IV. DNA Replication (cont)IV. DNA Replication (cont)3. Bonding of Bases3. Bonding of Bases

a. The new bonds are a. The new bonds are ________ ________ between nucleotidesbetween nucleotides

b. 2 strands are formed b. 2 strands are formed connected by a ________ connected by a ________

(This (This makes the chromosome makes the chromosome appear appear as an X)as an X)

DNA Replication DNA Replication ReenactmentReenactment

Using the materials Using the materials provided, You have 5 provided, You have 5

minutes to decide how minutes to decide how to model the steps of to model the steps of

DNA replication.DNA replication.

V. REVIEWV. REVIEWWhat is DNA?What is DNA?Why proteins important?Why proteins important?Why are enzymes Why are enzymes

important?important?What is the complimentary What is the complimentary

bases for AATGCCGTA?bases for AATGCCGTA?Who proposed the double Who proposed the double

helix model of DNA?helix model of DNA?

V. REVIEWV. REVIEWWhat are the 3 steps of What are the 3 steps of

DNA replication?DNA replication?

The Answer…The Answer…

DNA MUTATIONS!!!DNA MUTATIONS!!!1) Mutations occur in the 1) Mutations occur in the

DNA of an organism.DNA of an organism.2) If the mutation doesn’t kill 2) If the mutation doesn’t kill

the organism, it can be the organism, it can be passed on to the offspring! passed on to the offspring! 3) This is the basis for ALL 3) This is the basis for ALL

variation in organisms variation in organisms today!today!