Slide 1 of 37 Copyright Pearson Prentice Hall Nucleic Acids and Protein Synthesis

Slide 2 of 37 Copyright Pearson Prentice Hall Two Types of Nucleic Acids: 1. DNA 2. RNA Together they have the code and capability to make all necessary proteins.

Slide 3 of 37 DNA Copyright Pearson Prentice Hall Deoxyribonucleic Acid -our genetic code -code for making all proteins/enzymes = all our traits and cell reactions

Slide 4 of 37 Copyright Pearson Prentice Hall DNA is: Located: in the nucleus of all our cells. Makes up our: Chromosomes Number of chromosomes in each of our cells? from mom 23 from dad

Slide 5 of 37 Copyright Pearson Prentice Hall Chromosomes: -46 linear pieces/segments of DNA -Each piece is super coil into “bow tie” shaped structures during cell division.

Slide 6 of 37 Copyright Pearson Prentice Hall Supercoiling of DNA Approximately 6ft/cell ~ supercoils into mere nanometers

Slide 7 of 37 Copyright Pearson Prentice Hall Human Genome: - Is our complete set of genes that makes up a human. -there are 22,000 genes in our genome % of every humans genes is identical. There is only a.1% sequence variation from person to person

Slide 8 of 37 Copyright Pearson Prentice Hall Genes: segments of DNA that codes for 1 or more proteins. Each chromosome is made up of many genes.

Slide 9 of 37 Copyright Pearson Prentice Hall Every cell in your body has an exact copy of all 46 chromosomes but……. Cells are selective on what genes are read and proteins made. Ex/ skin makes collagen pancreas makes insulin testicles make testosterone

Slide 10 of 37 Copyright Pearson Prentice Hall -Mapped all of our genes. -Completed in Headed by James Watson

Slide 11 of 37 Copyright Pearson Prentice Hall

Slide 12 of 37 Copyright Pearson Prentice Hall Structure of DNA: 1. is a nucleic acid 2. made up of many nucleotides bonded together Each nucleotide is made up of: 1. A sugar “deoxyribose” 2. A phosphate 3. A nitrogen base (4 types)

12–1 DNA Slide 13 of 37 Copyright Pearson Prentice Hall The Components and Structure of DNA 3. There are four kinds of DNA nitrogen bases: Adenine Guanine Cytosine Thymine

12–1 DNA Slide 14 of 37 Copyright Pearson Prentice Hall 5. DNA has a double helix shape (twisted). 4. DNA is made up of a double strand of nucleotides held together with weak hydrogen bonds.

12–1 DNA Slide 15 of 37 Copyright Pearson Prentice Hall 6.DNA follows the “Base Pairing Rule” Adenine only bonds to Thymine Cytosine only bonds to Guanine Why?

12–1 DNA Slide 16 of 37 Copyright Pearson Prentice Hall DNA’s structure was determined by James Watson and Francis Crick In 1953.

12–1 DNA Slide 17 of 37 Copyright Pearson Prentice Hall The Components and Structure of DNA DNA Double Helix

12–1 DNA Slide 18 of 37 Copyright Pearson Prentice Hall Nobel Prize winners in 1962 ~ Crick and Watson

12–1 DNA Slide 19 of 37 Copyright Pearson Prentice Hall Watson: current head of the Human Genome Project Crick: died in 2004

12–1 DNA Slide 20 of 37 Copyright Pearson Prentice Hall DNA Replication: - DNA makes an exact copy of itself - Why? So cells can divide and each new cell has an exact copy of DNA. - Occurs in all cells -Some cells lose the ability to divide. Example: nerve, brain, heart -Some cells divide all the time: Example: skin, bone

12–1 DNA Slide 21 of 37 Copyright Pearson Prentice Hall -DNA replication requires enzymes. -Each chromosomes is over 20,000 nitrogen bases long so it happens in sections. Interesting but useless bits of knowledge: DNA is an invisibly thin, very long double strand of nucleotides. The DNA found in each human cell is almost 2 meters or 6 feet long. If all the DNA in a human adult were laid end to end the DNA molecule would stretch 113 billion miles. That would equal 610 trips to the sun and back.

Slide 22 of 37 Steps to DNA Replication: Copyright Pearson Prentice Hall 1.The enzyme DNA helicase unwinds and unzips DNA by breaking the hydrogen bonds between nitrogen base pairs at several places along each strand. 2.Creating several “replication bubbles”.

12–1 DNA Slide 23 of 37 Copyright Pearson Prentice Hall

12–1 DNA Slide 24 of 37 Copyright Pearson Prentice Hall 3. Two DNA polymerase enzymes, one on each side of the DNA strand add new nucleotides following the base pair rule.

12–1 DNA Slide 25 of 37 Copyright Pearson Prentice Hall

12–1 DNA Slide 26 of 37 Copyright Pearson Prentice Hall 4. This continues until 2 new but identical DNA molecules are created.

12–1 DNA Slide 27 of 37 Copyright Pearson Prentice Hall 6. Two new strands recoil and two new, identical molecules are formed. A T T C G T A A G C T A A G C A T T C G

12–1 DNA Slide 28 of 37 Copyright Pearson Prentice Hall DNADNA Replication

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