1. Modern Genetics How information is passed from parents to offspring

2. Do Now Front page of note packet Label the parts ( Hint: 2 boxes are the same)

3. What is the relationship between: The nucleus, genes and chromosomes? Nucleus – Contains the DNA (genetic material) of a cell Chromosome – a strand of DNA that is tightly coiled (humans have 46) Genes – Piece of a chromosome/DNA. There are thousands of genes on a chromosome. They code for the specific proteins/traits.

4. Chromosome We all have 23 pairs of chromosomes. One pair of chromosomes determines our sex. The other 22 pairs of chromosomes are non- sex chromosomes and determine things like hair color and eye color. DNA DNA contains all the genetic information for all our traits (tells cells how to make proteins) Gene Each chromosome is made up of many genes. Genes code for a specific trait (or protein). Different versions of a gene are called alleles (blue vs. green eyed) What is the relationship between: The nucleus, genes and chromosomes?

6. What is DNA? DNA Deoxyribonucleic Acid The genetic material of all living things This is what is passed on from parent to offspring DNA is the instructions for creating all the proteins of an organism (flesh, bones, traits)

7. What is DNA? DNA Found in the nucleus of every Eukaryotic cell Humans have 46 strands of DNA  DNA coiled up into chromosomes  23 chromosomes from the mother  23 chromosomes from the father Amount of DNA varies on the organism

8. How is DNA built? Deoxyribonucleic Acid DNA is made up of 2 long strands called nucleic acids Nucleic acids are made up of many small pieces called nucleotides Each nucleotide consists of 3 parts: 1.Simple sugar (Deoxyribose) 2.Phosphate 3.Nitrogenous Base (Base) Adenine (A) Thymine (T) Cytosine (C) Guanine (G)

9. Lets build DNA How many nucleotides do you need to make DNA? _____________________ Many nucleotides are linked together in long chains called nucleic acids! How many strands of nucleic acids make up a strand of DNA? _____________________ The two strands stay together because the bases are chemically bonded About 3 Billion 2

10. How do the bases bond? Nitrogenous Bases ♥ Adenine only bonds with Thymine ♥ “A” only connects with “T” ♥ Guanine only bonds with Cytosine ♥ “G” only connects with “C”  The bases form hydrogen bonds with matching bases and appear to be the steps in the DNA double helix ladder  DNA’s shape is referred to as a “Double Helix”

11. 1.How many nucleotides with adenine are there in this piece of DNA? 2.Therefore, how many thymine bases are there in this piece of DNA? 3.If 20% of a random piece of DNA is made of Guanine, what percent (%) of that piece of DNA is Cytosine? Do Now : Page 3 – Questions 1-3

12. Do Now (New York) Last page of note packet

15. Do Now (New York)

16. Does DNA Replicate? When does DNA replicate? 1. 2. DNA Replication  DNA makes new molecules with the same base sequence (instructions)  DNA makes an exact copy YES!! Once before Mitosis Once before Meiosis

17. Human DNA (46 chromosomes) Karyotype

18. How does DNA replicate itself? 1.The DNA strand is unwound by enzymes and each strand is separated into single strands 2.Matching (complementary) nucleotides floating around will attach to the single strands of DNA known as templates – What compound builds or connects matching nucleotides? 3.Two new identical strands of DNA are formed and each will become a double helix again.

19. Replication of DNA Parental DNA Nucleotides Both parental strands serve as templates Two identical daughter molecules of DNA

20. Replication of DNA

22. DO NOW pages 9 & 10 Questions: #1,2,8,9

23. DO NOW pages 9 & 10 Questions: #11,12,14,15

24. DO NOW pages 9 & 10 Questions: #1,2,8,9,11,12,14,15

25. DNA is not perfect; it makes mistakes  Any change in DNA sequence is called a mutation.  Can be caused by errors in replication, transcription, cell division, or by environmental factors – (mutagenic agents)  If a mutation occurs in gametes it will be ….. Since DNA contains the instructions for producing proteins, the mutation may result in a protein that does not work correctly. In some rare cases, a gene mutation may have positive effects. passed on to offspring

26. Mutations  If mutation takes place in a body cell, it is.... to the offspring Damage to a gene may impair the function of the cell When that cell divides, the new cells will have the same mutation Some mutations of DNA in body cells affect genes that control cell division causing uncontrollable cell growth & cell division a.k.a. cancer NOT passed on

27. Types of Mutations A point mutation is a change in a single base pair in DNA. A change in a single nitrogenous base can change the entire structure of a protein Replace G with A

28. More Types of Mutations Four types of rearrangement are deletion, duplication, inversion, & translocation

29. Frameshift Mutations Frameshift mutation  A mutation where a single base is added or deleted from DNA  This shifts the reading of codons by one base  This mutation would cause nearly every amino acid in the protein after the mutation to be changed

30. Why might mutations in DNA be a problem? Because DNA codes for all your bodies proteins and traits! Proteins will not form correctly!

31. DO NOW pages 9 & 10 Questions: #3,4,5,6,7

32. DO NOW pages 9 & 10 Questions: #10,13, 16, 17, 18, 19

33. From DNA to Proteins How does DNA code for all our traits and proteins (us)?

34. Genes ! The DNA (cookbook) contains the recipes (genes) for making proteins  Genes provide the instructions on how proteins should be assembled. Then – amino acid by amino acid– they assemble the protein  The sequence of amino acids determines the proteins shape and determines its function  Every cell has the same DNA, just different genes (parts of the DNA) are used! Nucleus  Chromosomes  Genes

35. What are some proteins & traits? – Enzymes, pigments, hemoglobin – Muscle & cartilage fibers – Make up part of the cell membrane – Cell receptors, hormones, membrane channels  There are about 35,000 genes in the human genome, so there are about 35,000 different proteins! 1.If DNA makes proteins, then how do cells communicate and know how to come together to make specific tissues and organs? 2.Do genes code for muscle size, good grades or if you’re going to be a star athlete? Cell Receptors & enzymes control molecule interactions and how cells come together! Nope… that’s all you.

36. RNA – Ribonucleic Acid DNA provides the instructions for protein synthesis and RNA does the actual work DNA & RNA difference: 1.Uracil replaces Thymine! a)“A” pairs with “U” b)“C” pairs with “G” 2.RNA is single stranded! 3.RNA has ribose sugar (RNA) instead of deoxyribose (DNA) DNARNA

37. DO NOW Note Packet – page 14 Complete the “Replication” Section

38. Types of RNA mRNA – (messenger RNA) is a copy of one gene that leaves the nucleus and goes to a ribosome tRNA – (transfer RNA) delivers the correct amino acid to the ribosome at the right time

39. Process of Making Proteins Protein Synthesis takes place in 2 steps: 1.Transcription 2.Translation

40. So, how are proteins made from the genes in our DNA?  Ribosomes Found outside the nucleus in the cytoplasm and are the sites for protein synthesis (building)  DNA never leaves the nucleus That’s weird! Then how do the instructions (DNA) leave the nucleus and get to the construction site (ribosome)? A Message!

41. 1. Transcription Is when the base sequence of a gene is copied making a single strand of mRNA in the nucleus  mRNA will leave the nucleus and enter the cell cytoplasm  mRNA will meet with a _________ where the instructions will be read (codon by codon  New base pairs: Ribosome A - U G - C

42. 1. Complete the complementary DNA strand 2. Make mRNA for this gene A – T – T – G – C – G – A – A – T – C – C – A Complimentary  DNA strand DNA strand  mRNA strand  DNA strand  A – T – T – G – C – G – A – A – T – C – C – A Complimentary  DNA strand RNA polymerase

43. 2. Translation Is when a ribosome reads the mRNA strand and makes a protein  mRNA carries the blueprint for the construction of a protein  tRNA delivers the proper amino acid to the proper site along the mRNA sequence.  Occurs in cytoplasm

44. 2. Translation Process:  Ribosomes read the mRNA strand THREE bases at a time  Each group of THREE bases in the mRNA strand are called codons  Codons code for specific amino acids What amino acid for these mRNA codons A A G U A U

45. 2. Translation  The ribosome will match a codon with the tRNA that has the correct anticodon  Every tRNA has a specific amino acid.  Specific DNA sequence + specific mRNA sequence = specific amino acid sequence  Specific amino acid sequence = specific shaped protein

47. Based on the mRNA sequence, you can figure out what the amino acid sequence will be! Find the missing Amino acids, mRNA codons and DNA triplets

48. mRNA codons code for specific amino acids

49. Why might mutations in DNA be a problem? Because DNA codes for all your bodies proteins and traits! Proteins will not form correctly!

50. How is the structure and function of the protein (polypeptide) determined? The shape (structure) & the function of the polypeptide (protein) is determined by the type of amino acids and the sequence the amino acids.

51. DO NOW The Genetic Code / Protein Synthesis worksheet http://www.pbs.org/wgbh/aso/tryit/dna/shockwave.html

52. DO NOW pages 9 & 10 Questions: #