Warm up 3/30 1. Where would you find DNA? 2. Does each cell in your body have different DNA, explain? 3. What does DNA look like? 4. Draw a picture of DNA.

Unit 5: DNA/RNA Pg. ___

DNA Structure Pg. ___

DNA History and Structure

Learning Targets (SOL BIO.5e,g)  I can explain what the structure of DNA looks like.  I can design and label the key parts of a DNA strand.

DNA Structure The DNA molecule is in the shape of a double helix twisted ladder spiral staircase

What is DNA made of? DNA is a polymer; Its monomers (building blocks) are made up of repeating structures called ___________ nucleotides

Review: What is a Nucleotide? A nucleotide is made up of three molecules: Phosphate group Deoxyribose (sugar) Nitrogenous base

DNA Nucleotide Deoxyribose (sugar) Phosphate group Nitrogenous base

Chargaff’s Rule Why is this significant? The percentage of adenine and thymine are almost equal. The percentage of guanine and cytosine in DNA are almost equal. A = T C = G

Base Pairing In 1949, Erwin Chargaff did research that showed that in the DNA from one organism, the amount of Adenine (A) = __________and the amount of ___________ = ____________. This suggested that nucleotides in DNA must occur in _______. Thymine (T) Guanine (G) Cytosine (C) pairs

Chargaff’s Rule In a DNA molecule the amount of Adenine = Thymine Cytosine = Guanine

1.A + T + C + G = 100% 2.Chargaff’s Rule A = T C = G 1.T = 10% Find the remaining values A = C = G = 2. C = 5% Find the remaining values A = T = G = 3. A= 40% Find the remaining values T = C = G = 4. A + T = 10% Find the remaining values A = T = C = G = 5. C + G = 20% Find the remaining values A = T = C = G = Human beings’ DNA is made up of 20% guanine, would you be able to calculate the percentages of the remaining nitrogenous bases?

Learning Targets (SOL BIO.5e,g) I can explain what the structure of DNA looks like. I can design and label the key parts of a DNA strand.

Exit Slip 1. Which of the following correctly describes the DNA molecule? A.Short staircase B.Double helix C.Spiral staircase D.Both B & C 2. If adenine = 20% find the values T= C= G= 3. Label the DNA molecule Deoxyribose, phosphate group, nitrogenous base