Unit 6 Guided Notes: 1 DNA Replication, Transcription, and Translation

A Gene is a Segment of DNA When a ___________________ is expressed, DNA is transcribed to produce RNA and RNA is then translated to produce ___________________________________. Genotype and Phenotype

• _____________________________________________________ 1. Genetic Composition of an Organism 2. Represents the __________________________________________ Properties 3. ________________ ___________________________________________

• ____________________________________________________ 1. The Expression of the Genes 2. What You See DNA

1. Double Stranded ______________________ 2. Subunits: __________________________ 3. Each subunit:

A. ________________________________________ B. ___________________________ group C. ___________________________ base

4. _________________ _________________ between Nitrogenous Base Pairs (rungs of a ladder) 5. Adenine-Thymine (_____ - _____) and Guanine-Cytosine (_____-_____) DNA codes for Proteins (and sometimes RNA)

• The sequence of _______________________________ in DNA codes for proteins!!!! – Order of ____________________ ______________________ – Central to cell function and life

• Tells the cell what to do, what to produce, and when to do it!!! DNA Between Organisms

DNA similarity between humans and chimps: ______________________________ DNA similarity between humans and mice: _________________________ DNA similarity between humans and bananas: ____________________

BETWEEN YOU AND ME? DNA within an Organism

• With few exceptions, _________ cells of an organism have the __________ __________ and ____________ number of chromosomes but _____________ in expression of genes

– Example: Skin cells have the same DNA as your brain cells. • ________________ organisms begin as undifferentiated masses of cells!

– Variation in gene expression and gene activity determines the – ______________________ of cells and ultimately their ______________________

Specialization • During differentiation, only _____________________ parts of the __________________ are activated (switches

on and off)

• The parts of the DNA that are activated determine the function and specialized structure of the cell

• ______________________ (like hormones) can act as switches to turn genes on or off in a cell

Unit 6 Guided Notes: 2 DNA Replication, Transcription, and Translation

Differentiation • Because all cells contain the same __________________ in a organism, all cells initially have the

_________________________ to become any type of cell

• But, once a cell differentiates, the process ____________________ reverse – The cell is _______________ in its cell cycle!

Stem Cells • _________________________________________________________________________________________________________________

_____________________________________________________________________________________ Types of Stem Cells

• ______________________________ – Not yet differentiated into various cells types

• ______________________________ – Differentiated into niches to produce specific types of cells

Stem Cell Niches in Humans (Adult Stem Cells!)

• _____________________ stem cell niche: neurons, nerve cells • ____________________ stem cell niche: osteocytes (bone cells) for growth and repair • Blood stem cell niche: ___________ _____________ ________________, white blood cells, platelets (controls

bleeding) • ________________________ stem cell niche: produces satellite cells which differentiate into muscle cells • ___________________ stem cell niche: ____________ and ______________

DNA Cell Structure Cell Function

Unit 6 Guided Notes: 3 DNA Replication, Transcription, and Translation

Cell Differentiation in Plants

Phloem: sugar two ways! Xylem: water up! Central Dogma of Biology Biological information only travels in one direction ___________ ___________ _________________________ Remember… Cells respond to their environment by producing different types and amounts of _____________________________. How? The process of _________________________ ____________________________. 3 parts: ____________________________ ____________________________ ____________________________ Replication

• The duplication of DNA which occurs during the S phase of ____________________. • 1 Strand 2 Complementary Strands • DNA Polymerase

– _________________________________ that lays down new strand of DNA using the old strand as a template.

DNA Replication

One of the strands of the ________________________ DNA molecule is from the _______________________________ DNA molecule. Daughter cells have an exact copy of parental DNA.

Unit 6 Guided Notes: 4 DNA Replication, Transcription, and Translation

DNA Structure

DNA Replication Step 1: Hydrogen bonds between complimentary nitrogen bases break _______________________________________, a specialized enzyme, unzips DNA Step 2: DNA strands ____________________ ________________________ from each other Step 3: DNA nucleotides in the cell match up with each side of the “unzipped” DNA Each “unzipped’ strands forms a _________________________________ for a new strand Step 4: Each “old’ strand forms a template for a “new” strand Two _________________________________ DNA molecules form ______________________________________________, a specialized enzyme, lays down new nucleotides to form new DNA molecules

thymine

adenine

cytosine

guanine

phosphate

deoxyribose sugar

DNA nucleotide

Deoxyribose sugar

phosphate

Nitrogenous base

(guanine)

RNA nucleotide

ribose sugar

phosphate

Nitrogenous base

(uracil)

Sugar / phosphate “strand” Nitrogenous base “rung”

Hydrogen bond

(H-bonds)

Unit 6 Guided Notes: 5 DNA Replication, Transcription, and Translation

Transcription • Occurs in the ____________________________________ • The process by which a molecule of DNA is copied into a ______________________________ strand of RNA. • 1 Strand DNA 2 Strands RNA • RNA Polymerase

– ______________________________ that transcribes DNA to RNA

– RNA grows in the 3’ to 5’ direction • Final product

– Messenger RNA (mRNA) – mRNA leaves the nucleus and moves onto the ___________________________________

DNA RNA

NO T in RNA!!! U REPLACES T

Words: Coding strand, template strand, mRNA

• Deoxyribonucleic acid

• Sugar: ____________________________

• Nitrogen bases: A, T, G, C

• Double-stranded

• Self-replicating

• Ribonucleic acid

• Sugar: ____________________

• Nitrogen bases: A, U, G, C

• No T (A bonds with U)

• Single strand

• Made only when needed

using DNA as a template

Unit 6 Guided Notes: 6 DNA Replication, Transcription, and Translation

RNA Transcription Step 1: _________________________________ ________________________ between complimentary bases break DNA “unzips” Step 2: DNA strands pull ___________________ from each other Step 3: RNA _________________________________ in the cell match up with only one side of the “unzipped” DNA Each “unzipped’ strands forms a ______________________________ for a mRNA strand Step 4: RNA nucleotides continue to match up with “unzipped” DNA until the message is completely transcribed Step 4: mRNA strand breaks off from the DNA strand Step 5: mRNA strand leaves the nucleus for the ______________________________ in the cytoplasm Step 6: Once the mRNA leaves, the DNA “zips” back together

Unit 6 Guided Notes: 7 DNA Replication, Transcription, and Translation

DNA Replication, Transcription, and Translation OVERALL GOAL: PROTEIN SYNTHESIS

PROTEINS CAN BE: ________________________________________ (forming a part of the cell materials) ________________________________________ (hormones, enzymes, or chemicals involved in cell chemistry)

Translation

• The process in which the information in the nucleotide base sequence of __________________________________ is used to dictate the amino acid sequence of a ________________________.

• 1 Strand RNA Amino Acid Chain Protein – Amino acids are linked by _______________________ _______________________ to form polypeptides – Polypeptide chains form protein molecules

• ___________________________________ = Transfer RNA

RNA and Protein Synthesis

• RNA is a _________________________ Stranded Nucleic Acid • RNA Acts as a ______________________________ between DNA and Ribosomes • Process Takes Amino Acids and Forms Proteins

Why is it Necessary?

• DNA / ________________________ • Ribosomes / ____________________________ • Need a Messenger

Definitions

• ___________________________________ 1. Three-base segment of _______________________ that specify amino acids. 2. Sense Codons 3. Nonsense Codons

• ____________________________________ 1. Three-base segment of _____________________ that dock with a codon. 2. Docking results in deposition of amino acid.

Unit 6 Guided Notes: 8 DNA Replication, Transcription, and Translation

Protein Synthesis • Proteins are coded directly from the mRNA with 3 bases (one codon) for each amino acid. What’s

up with that?

mRNA Codon Charts

• To read: – First letter, second letter,

third letter of codon of mRNA tells you the amino acid

Translate: mRNA: AUG GUG CAC AAU CAA UUU Protein Synthesis: Replication, Transcription, Translation

Words: Ribosome, Amino Acid, mRNA, Anti-Codon, Transcription, Codon, Translation, Protein (polypeptide chain), tRNA