DNA Replication and Protein Synthesis Review Lookabaugh Day 4 Review

DNA – Chemical that makes up your chromosomes “Deoxyribonucleic Acid” 1.Double stranded Helical ladder 2.Contains all genetic info Blueprint for whole body 3.In the nucleus 4.Made up of nucleotides Sugar: Deoxyribose sugar Phosphate group Nitrogen Bases- Adenine Thymine Cytosine Guanine

DNA Replication- DNA Replication- Happens in S phase(Interphase) when making a new cell Click blue link for Amoeba Sisters video Making a copy of DNA The complementary DNA to the following to TTG-GCA would be AAC-CGT. Enzymes cause this UNWINDING and UNZIPPING Remember make new DNA ALWAYS in 5’ to 3” direction. What does this mean?

RNA – 3 kinds(mRNA, tRNA and rRNA) Ribonucleic Acid 1.Single stranded 2.Made up of nucleotides 1.Sugar: Ribose 2.Phosphate group 3.Nitrogen Bases- 1.Adenine 2.Uracil 3.Cytosine 4.Guanine

What is DNA’s JOB? MAKE PROTEINS for the ORGANISM! SO….uses a process called PROTEIN SYNTHESIS This has 2 MAJOR PARTS DO YOU REMEMBER WHAT THEY ARE? ***Click on Blue link above and watch the video Review by the Amoeba Sisters

FIRST: Transcription –(SCRIBBLE down the code) DNA  mRNA rewriting DNA = TAT - CGA so RNA = AUA - GCU DNA is too large and wide to leave nucleus so a copy is made of just the section needed (mRNA)

STEP Two to make a Protein is “Translation” = decoding bases into language of proteins 1.mRNA leaves nucleus  finds a ribosome attached to ER 2.tRNA brings amino acids on tail to pair up with mRNA codon 3.tRNA’s will drop off amino acids and leave after they connect 4.When a STOP codon is detected on mRNA the protein(amino acid) strand will FALL off and get packaged by ER and Golgi for use where needed.

Protein Synthesis DNA is like the “whole instruction manual- BLUEPRINT”. RNA is like “the construction workers” reading the blueprint/instructions and then getting protein built.

Protein Synthesis mRNA has the 3 letter CODON which binds to the 3 base letters on tRNA which has the ANTICODON. There are 64 possible letter combos. Why do we only have 20 amino acids then?

Mutations changes in DNA sequence. caused by mutagens: radiation, chemicals or infectious agents. can also occur during replication, transcription or meiosis. benefit mutations are called adaptations. If occur in somatic cells (body cells) will not affect potential offspring. If occur in gamete cells (sex cells) can be passed on to offspring.

Mutations to DNA Point mutation – nitrogen base(A,T,C or G) in DNA sequence replaced with another. This may not affect the protein being made. Because of the WOBBLE EFFECT. (3 rd base) Frame shift mutations – nitrogen base(A,T,C or G) is mistakenly inserted or deleted from the DNA sequence. This almost always affects the protein being made.

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14 The diagram below shows models of nucleic acids. A segment of each model is highlighted. 13

15 14.Based on the model, which feature is a characteristic of DNA replication? A.The molecule makes chromatin fibers. B.The molecule is in the form of a triple helix. C.Sequence mutations occur in all DNA strands. D.Complementary bases pair together to form new DNA.

16 15.Which of the following would be produced if a messenger RNA strand is coded from the DNA sequence CCCGGAATT? A. CCCGGAAUU B. GGGCCTTAA C. AAATTCCGG D. GGGCCUUAA

16.Which amino acid sequence can be coded from the DNA sequence CAG TAG CGA? 17 A.Valine – Isoleucine – Glycine B.Valine – Aspartic Acid – Alanine C.Valine – Isoleucine – Alanine D.Valine – Phenylala nine – Alanine

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