1. Vocabulary Key Terms DNA DNA replication Codon Intron Exon Translation
Central Dogma
Transcription
RNA
mRNA
tRNA
Anticodon
Genes
Nucleotide
Nitrogen base
Amino Acids (AA)

2. Where in the cell are we looking at?

4. 5a. Know the general structures and functions of DNA, RNA & protein.

5. 12—1 The Components and Structure of DNA
What is the overall structure of the DNA molecule?
The Components and Structure of DNA
DNA is made up of ______________________.
A nucleotide is a monomer of nucleic acids made up of a five-carbon sugar called ________________, a phosphate group, and a nitrogenous base.

6. The Components and Structure of DNA
There are ______ kinds of bases in in DNA:
adenine
guanine
cytosine
thymine
DNA is made up of nucleotides. Each nucleotide has three parts: a deoxyribose molecule, a phosphate group, and a nitrogenous base. There are four different bases in DNA: adenine, guanine, cytosine, and thymine.

7. The Components and Structure of DNA
The backbone of a DNA chain is formed by ______________ and _______________ groups of each nucleotide.
The nucleotides can be joined together in any order.

8. The Components and Structure of DNA
Chargaff's Rules
Erwin Chargaff discovered that:
The percentages of _________________ [G] and _____________________ [C] bases are almost equal in any sample of DNA.
The percentages of ________________ [A] and __________________ [T] bases are almost equal in any sample of DNA.

9. The Components and Structure of DNA
X-Ray Evidence 
______________________ used X-ray diffraction to get information about the structure of DNA.
She aimed an X-ray beam at concentrated DNA samples and recorded the scattering pattern of the X-rays on film.
This X-ray diffraction photograph of DNA was taken by Rosalind Franklin in the early 1950s. The X-shaped pattern in the center indicates that the structure of DNA is helical.
Photo credit: ©Cold Spring Harbor Laboratory Archives/Peter Arnold, Inc.

10. The Components and Structure of DNA
The Double Helix 
Using clues from Franklin’s pattern, James Watson and Francis Crick built a model that explained how DNA carried information and could be copied.
Watson and Crick's model of DNA was a ___________ _____________ in which _____ strands were wound around each other.

11. Who Discovered the DNA molecule?
Discovery of DNA:
___________: Proposed that DNA is made of 2 chains of nucleotides joined together by the nitrogen bases
Double Helix: DNA composed of 2 strands twisted together
James Watson & Francis Crick

12. The Components and Structure of DNA
DNA Double Helix
DNA is a double helix in which two strands are wound around each other. Each strand is made up of a chain of nucleotides. The two strands are held together by hydrogen bonds between adenine and thymine and between guanine and cytosine.

13. The Components and Structure of DNA
Watson and Crick discovered that ____________________ bonds can form only between certain base pairs—adenine and thymine, and guanine and cytosine.
This principle is called ________________.

14. From DNA to Protein Why is DNA Important?
All of the characteristics that you have are affected by the _____________ that you have in your cells.
Controls the color of your eyes, hair, or if you can digest milk.
______________ the order of the amino acids Δ’s the kind protein made.

15. From DNA to Protein RNA: _____________________ Acid a nucleic acid
single stranded
Sugar in RNA is ribose
Instead of Thyamine, Uracil (U) – (A) H

16. Three Types of RNA Help to build proteins
Messenger RNA (___________): brings info from the DNA in the nucleus to the cell’s factory floor, the cytoplasm.
Ribosomal RNA (_________): clamp onto the mRNA and use its info to assemble the amino acids in the correct order
Transfer RNA (___________): transports amino acids to the ribosome to be assembled into protein

17. RNA Facts RNA exists in many structural forms
mRNA: serves as a __________ during protein synthesis
tRNA
rRNA

18. DNA vs. RNA Deoxyribose sugar Adenine Guanine Cytosine ______________
2 strands
Ribose sugar
Adenine
Guanine
Cytosine
___________
One Strand

19. Proteins
Proteins are ________________ composed of amino acid ______________.
Different types of proteins function as enzymes and transport molecules, hormones, structural components of cells, & antibodies that fight infection.

21. 1d. Know the central dogma of molecular biology outlines the flow of information from transcription of ribonucleic acid (RNA) in the nucleus to translation of proteins on ribosomes in the cytoplasm.

23. 12-2 Chromosomes and DNA Replication
Photo credit: Jacob Halaska/Index Stock Imagery, Inc.

24. DNA and Chromosomes DNA and Chromosomes
In prokaryotic cells, DNA is located in the __________________.
Most __________________ have a single DNA molecule containing nearly all of the cell’s genetic information.

25. DNA and Chromosomes E. Coli Bacterium Chromosome
Most prokaryotes, such as this E. coli bacterium, have only a single circular chromosome. This chromosome holds most of the organism’s DNA.
E. Coli Bacterium
Bases on the Chromosomes

26. DNA and Chromosomes
Many eukaryotes have ________ times the amount of DNA as prokaryotes.
Eukaryotic DNA is located in the cell ______________ inside chromosomes.
The number of chromosomes varies widely from one species to the next.

27. DNA and Chromosomes Chromosome Structure
Eukaryotic chromosomes contain DNA and protein, tightly packed together to form _______________.
Chromatin consists of DNA tightly coiled around proteins called ______________________.
DNA and histone molecules form nucleosomes.
Nucleosomes pack together, forming a thick fiber.

28. DNA and Chromosomes Eukaryotic Chromosome Structure Chromosome
Nucleosome
DNA double helix
Coils
Supercoils
Eukaryotic chromosomes contain DNA wrapped around proteins called histones. The strands of nucleosomes are tightly coiled and supercoiled to form chromosomes.
Histones

29. DNA Replication What happens during DNA replication? DNA Replication
Each strand of the DNA double helix has all the information needed to reconstruct the other half by the mechanism of base pairing.
In most prokaryotes, DNA replication begins at a single point and continues in two directions.

30. DNA Replication
In eukaryotic chromosomes, DNA replication occurs at hundreds of places. Replication proceeds in both directions until each chromosome is completely copied.
The sites where separation and replication occur are called ____________________.

31. DNA Replication Duplicating DNA
Before a cell divides, it duplicates its DNA in a process called ____________________.
Replication ensures that each resulting cell will have a complete set of DNA.
During DNA replication, the DNA molecule separates into ______ strands, then produces two new complementary strands following the rules of base pairing. Each strand of the double helix of DNA serves as a template for the new strand.

32. DNA Replication New Strand Original strand Nitrogen Bases Growth
During DNA replication, the DNA molecule produces two new complementary strands. Each strand of the double helix of DNA serves as a template for the new strand.
Replication Fork
Replication Fork
DNA Polymerase

33. DNA Replication How Replication Occurs
DNA replication is carried out by enzymes that “unzip” a molecule of DNA.
Hydrogen bonds between base pairs are broken and the two strands of DNA unwind.
The principal enzyme involved in DNA replication is _______________________.
DNA polymerase joins individual nucleotides to produce a DNA molecule and then “proofreads” each new DNA strand.

34. DNA Replication
__________________ breaks up the hydrogen(H+) bonds between the nitrogen bases that holds the 2 strands together—unzips the DNA molecule
Free floating _______________ bond to the single strands by base pairing
Another _______________ bonds these new nucleotides into a chain

35. DNA Replication
4. This process continues until the entire molecule has been unzipped and replicated.
5. Each new strand formed is a _________________ of the original, or parent, strands.
6. The result is the formation of two DNA molecules, each of which is __________________ to the original DNA molecule.

36. 12-3 RNA and Protein Synthesis

37. 12–3 RNA and Protein Synthesis
_______________ are coded DNA instructions that control the production of proteins.
Genetic messages can be decoded by copying part of the nucleotide sequence from DNA into RNA.
_______________ contains coded information for making proteins.

38. The Structure of RNA The Structure of RNA
RNA consists of a long chain of nucleotides.
Each nucleotide is made up of a ___-carbon sugar, a phosphate group, and a nitrogenous base.
There are three main differences between RNA and DNA:
The sugar in RNA is ribose instead of deoxyribose.
RNA is generally single-stranded.
RNA contains ______________ in place of thymine.

39. Types of RNA What are the three main types of RNA? Types of RNA
There are three main types of RNA:
_________________ RNA
ribosomal RNA
_______________ RNA

40. Types of RNA
The three main types of RNA are messenger RNA, ribosomal RNA, and transfer RNA.
Messenger RNA (mRNA) carries ______________ of instructions for assembling amino acids into proteins.

41. Types of RNA
Ribosome
Ribosomal RNA
The three main types of RNA are messenger RNA, ribosomal RNA, and transfer RNA. Ribosomal RNA is combined with proteins to form ribosomes.
Ribosomes are made up of proteins and ribosomal RNA (rRNA).

42. Types of RNA
Amino acid
The three main types of RNA are messenger RNA, ribosomal RNA, and transfer RNA.
Transfer RNA
During protein construction, transfer RNA (tRNA) transfers each amino acid to the _________________.

43. Transcription What is transcription? Transcription
RNA molecules are produced by copying part of a nucleotide sequence of DNA into a complementary sequence in RNA. This process is called ______________________.
Transcription requires the enzyme ___________________________.

44. Transcription
During transcription, RNA polymerase binds to DNA and separates the DNA strands.
RNA polymerase then uses one strand of DNA as a template from which nucleotides are assembled into a strand of RNA.
RNA polymerase binds only to regions of DNA known as ______________________.
Promoters are signals in DNA that indicate to the enzyme where to bind to make RNA.

45. Transcription Steps __________________ unzip the molecule of DNA
Free RNA nucleotides pair with complementary DNA nucleotides on one of the DNA strands
AGC TAA CCG  ______ strand
UCG AUU GGC  _____ strand
When the base pairing is completed, the mRNA molecule breaks away as the DNA strands rejoin.
The ______________ leaves the nucleus and enters the cytoplasm

46. Transcription RNA RNA polymerase DNA
During transcription, RNA polymerase uses one strand of DNA as a template to assemble nucleotides into a strand of RNA.

47. RNA Editing RNA Editing
The DNA of eukaryotic genes contains sequences of nucleotides, called __________________, that are not involved in coding for proteins.
The DNA sequences that code for proteins are called _________________.
When RNA molecules are formed, introns and exons are copied from DNA.

48. RNA Editing The ____________ are cut out of RNA molecules.
Exon
Intron
DNA
The ____________ are cut out of RNA molecules.
The _____________ are the spliced together to form mRNA.
Pre-mRNA
mRNA
Many RNA molecules have sections, called introns, edited out of them before they become functional. The remaining pieces, called exons, are spliced together. Then, a cap and tail are added to form the final RNA molecule.
Cap
Tail