Biology Cp Study Guide (dna, Rna, & Protein Synthesis) Answer Key

Biology CP Study Guide (DNA, RNA, & Protein Synthesis) Name _____________________________________________

Date _____________

The Structure of DNA: 1. DNA contains instructions for… Proteins 2. Chromosomes are made of… DNA 3. The shape of a DNA molecule is called (hint – another name for twisted ladder)… Double Helix 4. The backbone (nucleotide) of DNA is made of three parts… Sugar, Phosphate, Nitrogen Bases 5. The bases are made of (hint – starts with N)… Nitrogen 6. DNA has four different bases. They are called… Adenine, Thymine, Guanine, Cytosine 7. Some bases have a 1-ring structure; we refer to these as (hint – starts with a Py) Pyrimidines Some bases have a 2-ring structure; we refer to these as (hint – starts with a Pu) Purines 8. Which two bases have a 2-ring structure? (Adenine & Guanine, or Thymine & Cytosine?) Which two bases have a 1-ring structure? (Adenine & Guanine, or Thymine & Cytosine?) 9. What kinds of bonds are formed between the bases in DNA? Are they strong or weak bonds? Hydrogen Bonds; Weak – allows for DNA Replication 10. Which bases are complimentary (always join together)? A  T C  G 11. How many meters of DNA does each cell contain? ~ 2m DNA Replication: 1. Are the bonds between the sugars and phosphates strong or weak? Why do you think that is important? Strong; DNA will not fall apart 2. What is the definition of replication? Process by which DNA unwinds and makes copies of itself

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3. What is the enzyme that is responsible for DNA replication? DNA Polymerase 4. What is the first step that occurs in replication? (Not On Test) 5. What happens after the DNA strand is unzipped? (Not On Test) 6. How many copies are DNA are present after replication? (Two complete Identical Copies) 7. What is the final job of DNA Polymerase at the end of replication? Proofreading DNA Technology: 1. The procedure in which DNA is pulled out/extracted from cells is called… Spooling 2. Enzymes that cut DNA at specific sequences are called… Restriction Enzymes 3. DNA can be separated based on ________ & ________. Size and Charge 4. The process in which DNA is separated in a gel with an electric current running through it is called… Electrophoresis 5. Negative DNA moves toward the ____________ end in Electrophoresis. Positive 6. Which moves faster and farther? (Smaller or Bigger fragments of DNA) Smaller fragments 7. DNA can be copied through a process called….(Hint- initials are PCR) Polymerase Chain Reaction 8. What is the definition of a clone? Member of a Group of Genetically Identical Cells 9. How are organisms cloned? Body cell merges with an egg cell

From Genes to Proteins (Protein Synthesis): 1. What are three ways DNA differs from RNA? (Hint – make a table) TABLE SHOWN ON NEXT PAGE

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DNA and RNA differ in 3ways RNA

DNA



SingleSingle-stranded



DoubleDouble-stranded



Ribose (sugar)



Deoxiribose(suga Deoxiribose(sugar)



Uracil (base)  bonds to Adenine Adenine



Thymine (base (base)  bonds to Adenine Adenine

2. What happens in Transcription? (DNA info is transferred to…) RNA 3. What is the enzyme involved in Transcription? RNA Polymerase 4. What happens in the 1st step of Transcription? (Not on test) 5. What happens in the 2nd step of Transcription? (Not on test) 6. What happens in the 3rd step of Transcription? (Not on test) 7. What is the name of the base that RNA has that takes the place of Thymine? Uracil 8. What are the 3 types of RNA called? mRNA, tRNA, rRNA 9. mRNA has information in 3-nucleotide sequences called… Codons 10. In Translation, RNA is coded for… Amino Acids 11. Where does Translation take place? Ribosomes (in Cytoplasm) 12. tRNA molecules have two parts: an Amino Acid and… Antocodons 3

13. rRNA molecules are made of 1 mRNA molecules and 2… tRNA molecules 14. What is the organelle in which protein synthesis takes place (Hint – think about what rRNA stands for…) Ribosomes 15. Know the 7 steps in Translation: (LOOK AT PAGE 210 & 211) 1- mRNA start codon starts the process at the P site. 2- the next tRNA bonds to the next codon at the A site. 3- A & P are holding 2 tRNA’s…a peptide bond is formed between 2 amino acids. 4- tRNA detaches from P-site, leaves behind amino acid, leaves Ribosome. 5- tRNA at A-site moves to the P-site. Now a new codon is ready at the A-site for another tRNA. 6- tRNA detaches from P-site, leaves behind amino acid, leaves ribosome. 7- (Steps 2 – 6 repeat until a stop codon is reached). Ex. UAG, UAA, UGA.  A new protein is then released into the cell. 16. What kinds of bonds are formed between amino acids? Peptide

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