130 likes | 215 Vues
All about DNA. Structure, Building Blocks, and Replication. DNA Structure-Review. REVIEW! Which type of organic molecule is DNA? NUCLEIC ACID!! DNA stands for DEOXYRIBONUCLEIC ACID Building Blocks of Nucleic Acids = NUCLEOTIDES Or subunits. DNA Structure- Nucleotides.
E N D
All about DNA Structure, Building Blocks, and Replication
DNA Structure-Review • REVIEW! • Which type of organic molecule is DNA? • NUCLEIC ACID!! • DNA stands for DEOXYRIBONUCLEIC ACID • Building Blocks of Nucleic Acids = • NUCLEOTIDES • Or subunits
DNA Structure- Nucleotides • Each nucleotide is made of 3 parts: • Sugar (Deoxyribose) • Phosphate • 1 of 4 Nitrogenous Bases: • A = adenine • T = thymine • C = cytosine • G = guanine • So which part of a nucleotide changes?? • THE NITROGEN BASE!!!!! • So how many different nucleotides are there for DNA? • Four (4)
DNA Shape and Form • DNA IS DOUBLE STRANDED • STRANDS TWIST TO FORM DOUBLE- HELIX • NITROGEN BASES BIND TOGETHER TO MAKE TWO STRANDS • Aalways binds with T • Calways binds with G ****THIS IS CALLED THE BASE-PAIR RULE!**** • Now, on your notesheet, fill in the COMPLEMENTARY strand using the BASE-PAIR rule!
DNA Structure • Let’s Practice Again! • One strand of DNA has the sequence you see. What is the complimentary strand’s sequence???
Replication: The Video Clip http://www.youtube.com/watch?v=z685FFqmrpo
DNA Replication (Copying) CLICK HERE FOR DEMO • When does DNA need to be copied???? • BEFORE any CELL DIVISION! • DNA acts as a PATTERN or TEMPLATE to make copies of itself! • Steps of DNA Replication: • First, two (2) strands are “unzipped” by enzymes • Second, other enzymes bring new subunits (nucleotides) to these separated strands • Each strand acts as a template to build a new DNA molecule • Third, you end up with 2NEW identical double helices CLICK HERE FOR DEMO #2
DNA Replication Diagram Parent Strands New complimentary strands Free Floating Nucleotides
Replication Practice- Step 1 “Unzip” Enzymes UNZIP
Replication Practice- Step 2 Add Subunits using Base-Pair Rule
THE DNA RAP!!!! • http://www.youtube.com/watch?v=d1UPf7lXeO8