Warm-Up: Find the 6 differences between the two pictures.
Source: The answers are Answers: Fish gill, tree stump, cats foot, dogs mouth, birds beak, dogs ear Source: Objective SWBAT explain why variations in nitrogenous base sequences aid in the distinctiveness of an individual. Copyright 2013 Crosscutting Concepts, LLC. All Rights Reserved. Agenda DNA Paper Model OJ Simpson Documentary Genes
Identifying Characteristics of DNA Extract Your Own DNA Exit Slip Copyright 2013 Crosscutting Concepts, LLC. All Rights Reserved. DNA Paper Model OJ Simpson Documentary Analysis Questions
Where does OJ claim that he was when the murder was committed? What was some evidence that was found at the crime scene? What did the forensic evidence show with Ron Goldman? What did the detective find when they arrived at OJ Simpsons house? Why was OJ Simpson the prime suspect? What did detectives notice when OJ Simpson arrived back from Chicago? Genes Cellular Blueprints
A gene is a series of nucleotides that codes for a certain polypeptide (protein).Each gene has at least Promoter region Initiation or start site Coding region Termination site Eukaryotic genes can be as large as 100,000 base pairs. Introns are non-coding regions, usually spliced out of created proteins Exons are coding regions Copyright 2013 Crosscutting Concepts, LLC. All Rights Reserved. Chromosomes DNA Packaging
DNA is not floating loose inside the nucleus most of the time it is wrapped tightly around special proteins called histones in structures called chromosomes. There are two special chromosomes known as X and Y which determine the sex of an individual. Almost all individuals have two of these chromosomes. An XX combination is a female An XY combination is a male A YY combination is impossible All other chromosomes those which do not determine sex are known as autosomes. Copyright 2013 Crosscutting Concepts, LLC. All Rights Reserved. Chromosomes DNA Packaging
Almost all human cells are diploid each of our 23 chromosomes come in pairs.One half of each pair comes from the mothers haploid egg (containing only one copy of each chromosome); the other half comes from the fathers haploid sperm. The two chromosomes in each pair are called homologous chromosomes because they each carry similar genes controlling the same inherited characteristics. The prefix homo means same or similar what other scientific terms use it? Copyright 2013 Crosscutting Concepts, LLC. All Rights Reserved. Copyright 2013 Crosscutting Concepts, LLC. All Rights Reserved.
Sexual Reproduction Two parents give rise to offspring that have unique combinations of genes inherited from the two parents. Each chromosome pair is distinct and different and contains different genes. Copyright 2013 Crosscutting Concepts, LLC. All Rights Reserved. The pair of alleles inherited from your parents is called a genotype.
Sexual Reproduction Each of the two members of a chromosome pair can have slight differences in the DNA sequences of the genes it contains. Different versions of the sequence in the same gene are called alleles. The pair of alleles inherited from your parents is called a genotype. Copyright 2013 Crosscutting Concepts, LLC. All Rights Reserved. Sexual Reproduction If an individual has inherited the same gene sequences from mom and dad, they are homozygous for those alleles.If they inherit different sequences, they are heterozygous. Which of these offspring squares are homozygous and which are heterozygous? Copyright 2013 Crosscutting Concepts, LLC. All Rights Reserved. Heterozygote: individual having two different alleles at a genetic location
Homozygote: individual having two copies of the same allele at a genetic location Copyright 2013 Crosscutting Concepts, LLC. All Rights Reserved. Everyones DNA has the same basic makeup
Its the sequence of the base pairs that makes us different! Therefore we can USE that sequence to identify a person! However, there are MILLIONS of base pairs, so scientists use a shorter method, they analyze repeating sequences (Tandem Repeating Sequences) OJ Simpson Documentary
7. What was a key discovery for police on Simpson? 8. What happened when there was a warrant for Simpsons arrest? 9. Why was the Bronco a key crime scene? 10. What evidence did police dismiss or ignore? 11. Why do some think that Simpson should have had more wounds/bruises? 12. Where did Simpson say the cuts came from? 13. What did the fingernail evidence suggest? Exit Slip October 7, 2014 1. Get out a mobile device or use one of the computers and go to m.socrative.com. You can also use one of the iPads that has the Socrative app. 2. When prompted, enter for the room number. QUESTION: How does the nitrogen base structure provide an identifying characteristic to DNA?