Flashback Wednesday Jan. 7 Remember to put the date and write the question and answer. 1. What are the 3 parts of a DNA nucleotide? 2. What are the 4 bases in DNA?

Flashback Thursday Jan. 8 Remember to put the date and write the question and answer. 1. How many hydrogen bonds are between Cytosine and Guanine? Adenine and Thymine? 2. What is the name of the sugar in DNA?

Flashback Wednesday Jan. 7 Remember to put the date and write the question and answer. 1. What is the shape of DNA called? 2. The ____________are found on the sides of the ladder, while the ___________ are found on the rungs of the ladder.

DNA Structure DNA consists of two molecules that are arranged into a ladder-like structure called a Double Helix. A molecule of DNA is made up of millions of tiny subunits called Nucleotides. Each nucleotide consists of: 1. Phosphate group 2. Pentose sugar 3. Nitrogenous base

Cool Facts: One chromosome has million base pairs. DNA is found in the mitochondria. mDNA is only found in the egg. Sperm has no mitochondria so mDNA is passed to offspring from the mother. One sequence of DNA is a genome or gene. Unwind all our DNA, it will stretch from the moon and back 6000X.

Nucleotides Phosphate Pentose Sugar Nitrogenous Base

Nucleic Acid: CHO, CHO, CHON, ???

Nucleotides The phosphate and sugar form the backbone of the DNA molecule, whereas the bases form the “rungs”. There are four types of nitrogenous bases. A nucleotide is a small piece of a DNA molecule

Nucleotides A Adenine T Thymine G Guanine C Cytosine

Nucleotides Each base will only bond with one other specific base. 1. Adenine (A) 2. Thymine (T) 3. Cytosine (C) 4.Guanine (G) Form a base pair.

Chargaff’s Rule Adenine Thymine Adenine must pair with Thymine GuanineCytosine Guanine must pair with Cytosine about the same Their amounts in a given DNA molecule will be about the same. EXAMPLE: IF THERE IS 30% A, THERE MUST BE 30% T G C TA

Chargaff’s Rule Chargaff discovered that the percentage of A and T were equal. The same for C and G. This observation became Chargaff’s rule. This is always the same no matter what organisms.

BASE-PAIRINGS 2 Bonds CG H-bonds T A 3 bonds

Nitrogenous Bases PURINES PURINES Adenine (A) 1.Adenine (A) Guanine (G) 2.Guanine (G) PYRIMIDINES PYRIMIDINES Thymine (T) 3.Thymine (T) Cytosine (C) 4.Cytosine (C) T or C A or G

DNA Structure Because of this complementary base pairing, the order of the bases in one strand determines the order of the bases in the other strand. “Complementary Rule” “Complementary Rule”

G G A T T A A C T G C A T C

DNA Structure To crack the genetic code found in DNA we need to look at the sequence of bases. The bases are arranged in triplets called codons. A G G - C T C - A A G - T C C - T A G T C C - G A G - T T C - A G G - A T C

A gene is a section of DNA that codes for a protein. Each unique gene has a unique sequence of bases. This unique sequence of bases will code for the production of a unique protein. It is these proteins and combination of proteins that give us a unique phenotype.

Exit Slip Write the complimentary side of this strand of DNA on a half sheet of paper and turn in before you leave: AGTTCAGT

Protein DNA Gene Trait

Your Task Draw a flow chart to show how to get from:

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