DNA
DNA
Deoxyribonucleic Acid
UNIT 5: Chapter 12
AIM:
•Explain how the genetic code is contained within
DNA.
Organizational Level of Genetics
Define these terms:
Histones-
Nucleosome-
Chromosome
Supercoils
Coils
Nucleosome
Histones
DNA
double
helix
Interesting Facts About DNA
• DNA is used to solve many historical mysteries
• One single cell contains two meters of DNA.
• If you unraveled all your chromosomes from all of your cells and laid out the DNA end to end, the strands would stretch from the Earth to the Moon about 6,000 times.
http://www.indiana.edu/~ensiweb/connections/genetics/dna.mes.pdf (DNA nitrogenous base message)
http://www.johnkyrk.com/DNAanatomy.html
(DNA animation)
http://www.genome.gov/page.cfm?pageID=10002096
(genetics library)
What is the function (job) of DNA?
Passed down to us from our parents. DNA stores the CODE for directing the
construction of proteins within a cell. These proteins determine the phenotype of an organism.
Recall, DNA is a nucleic acid—A MACROMOLECULE.
DNA Structure
DNA is a double helix (spiral) that resembles a ladder.
DNA is made up of 3 things:
1. Phosphate 2. Deoxyribose (sugar,
yes, sugar) 3. Nitrogenous Bases
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DNA structure
Hydrogen bonds
Nucleotide
Sugar-phosphate backbone
Key
Adenine (A)
Thymine (T)
Cytosine (C)
Guanine (G)
Nucleotide
Remember
DNA is like an Oreo
Phophates + sugars = cookieBases = cream filling
How is the DNA code read?
There are 4 nitrogenous bases (molecules):
1. Adenine (A)
2. Thymine (T)
3. Cytosine (C)
4. Guanine (G)
DNA bases are complimentary
BASE PAIRING RULE:
__________________________
(A) (T)
ADENINE ----------------- THYMINE
(C) (G)
CYTOSINE -------------- GUANINE
DNA Youtube Video
• http://www.youtube.com/watch?v=qy8dk5iS1f0
2 Groups of BasesPurines Pyrimidines
Adenine Guanine Cytosine Thymine
Phosphate group Deoxyribose
MODE 1:
Find the complementary base sequence for the following DNA strand:
Strand 1:Strand 2: ACTTTACTTTACCGGGGG Strand 1: CGTGTGGAAATCGGTTGAStrand 2:
Remember
DNA is like an Oreo
Phophates + sugars = cookiesBases = cream filling
Why are some people better at sports than others?
• http://www.pubinfo.vcu.edu/secretsofthesequence/playlist_frame.asp
• Gene called ACE
Who has healthier DNA, one is exercises of a couch potato?
• http://www.wwaytv3.com/video/study_lack_of_exercise_hurts_dna/01
Check out the video.
M phase
G2 phase
S phase
G1 phase
Figure 10–4 The Cell CycleSection 10-2
DISEASES
Can be caused by 2 things:
1. The environment that surrounds you.
2. Your genes.
http://www.youtube.com/watch?v=kBfWybm0218&feature=related
(vytorin commercial)
Promoter Start signal
Gene Stop signal
Gene Sequence
Section 14-3
Locating GenesHow do scientists locate genes on DNA? Why is this important?
Scientists can locate genes by looking at DNA base sequence. IdentificationOf gene location is important for benefits of medicine and curing diseases.
Examples of Genetic Diseases
• Pg. 345 in Prentice Hall hardcover/online
DNA Technology• Forensic identification is an example of the application of DNA
technology.
• There is great potential for the development of useful products through genetic engineering (e.g., human growth hormone, insulin, and resistant fruits and vegetables).
• Eugenics, a pseudo-science of selective procreation, was a movement throughout the twentieth century, worldwide as well as in Virginia, that demonstrated a misuse of the principles of heredity.
• The Human Genome Project is a collaborative effort to map the
entire gene sequence of organisms. This information will be useful in detection, prevention, and treatment of many genetic diseases.
• PCR, electrophoresis, cloning are also examples.
Chapter Review (DNA)
• What is the function of DNA?
• What does DNA need to be copied (replicated)? What phase of the cell cycle does a cell make more DNA? (G1, S, G2 or M phase)
• How is the DNA code read?
• What are the 4 nitrogenous bases?
• What are 3 components of DNA?