Unformatted text preview: The Integumentary System The Integumentary System
More Than Skin Deep Cell Cycle TAKS TAKS
• TAKS Objective 2 – The student will demonstrate an understanding of living systems and the environment. TEKS TEKS
• The student knows the structures and functions of nucleic acids in the mechanisms of genetics. The student is expected to (A)describe components of deoxyribonucleic acid (DNA); and illustrate how information fro specifying traits of an organism is carried in the DNA; (B)explain replication, transcription, and translation using models of DNA and ribonucleic acid Engage Engage
• Humans shed their •
entire epidermis every 15 to 30 days. Bloodhounds detect this upon tracking Explore 1: Cell Cycle Research Explore 1: Cell Cycle Research
• Student will complete a cell cycle diagram with detailed description of cellular activity in each of the cell cycle phases. Cell Cycle Cell Cycle Explain: Cell Cycle Explain: Cell Cycle
• All cells constantly replace themselves by a process called mitosis, which is a small section of the cell cycle. • New skin cells push the older generation of cells toward the surface of the skin, where they are finally shed as a flakelike, lifeless, residue What are the two main phases of the cell cycle? Cell Cycle
includes Interphase M phase (Mitosis) is divided into is divided into G1 phase S phase G2 phase Prophase Metaphase Anaphase Telophase The Cell Cycle? Cell cycle - changes a cell goes through during its life span. contains 2 main steps.
1.Interphase (LONGEST phase of the cell cycle and has three parts) G1 (Everyday Cellular Activity) S (DNA Synthesis) G2 (Other Organelles Replicated) 2. M-Phase or Mitotic Phase (Shortest phase) Mitosis (Nuclear Division) Cytokinesis (Cytoplasm Division) Explore 2: S Phase Berry Full of DNA Lab Photo 51 Scientific contributions to the discovery of the DNA structure. Review: Interphase (G1)
1 • What is the main purpose of a cell that is in G1? Section 12-1 Explain: DNA
Adenine Guanine Pyrimidines
Cytosine Thymine Phosphate group Deoxyribose Section 12-1 Structure of DNA
Nucleotide Hydrogen bonds Sugar-phosphate backbone
Adenine (A) Thymine (T) Cytosine (C) Guanine (G) DNA Deoxyribose Sugar Base Pairs A-T G-C Phosphate What is a Nucleotide?
The basic building block of nucleic acids containing a sugar, base, and a phosphate.
P B S
S = Deoxyribose Sugar or Ribose Sugar B = Adenine, Guanine, Cytosine, Thymine or Uracil P = Phosphate Sugar Bases (Nitrogenous Bases) These chemicals are often called nitrogenous bases because of the high content of nitrogen (N) atoms Purines Pyrimidines 1) Cytosine (C) 2) Thymine (T) 3) Uracil (U) Phosphate Nucleotide The Sugar and the Phosphate make up the backbone of the structure The bases make up the rungs of the ladder Different Types of Nucleotides in DNA
| P P Deoxy---Cytosine Deoxy----Guanine
| | P P Many Nucleotides Together Parts of DNA and RNA Have a Sugar/Phosphate Backbone Bases make up the steps of the ladder A-T---DNA A-U---RNA G-C---DNA & RNA DNA Structure QuickTime™ and a Cinepak decompressor are needed to see this picture. Practice On your paper, complete the missing DNA strand by adding the complementary bases.
ATCGTTGCCATC TAGCAACGGTAG DNA Replication A Closer Look
» » » » DNA before replication: 1 double helix » double » DNA after replication: 2 identical helixes Section 12-2 DNA Replication
New strand Original strand DNA polymerase Growth
DNA polymerase Growth Replication fork Replication fork Nitrogenous bases New strand Original strand Getting Ready Step 1 Unwinding and Unzipping Unwind and Unzip Helicase Enzyme Step 2 Separates Polymerase Enzyme Step 3 Picking up Complementary Bases Separation and Adding Bases 5’----3’ Step 4 Rewind Two New DNA Molecules
• Each DNA Molecule with a Parent and Daughter Strand Interphase (G2)
2 Elaborate: DNA Jewelry ...
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