Unit 6: Protein Synthesis Study Guide KEY – Flashcards
Unlock all answers in this set
Unlock answersquestion
1. Why is the nucleus called the control center of the cell?
answer
It manages all of the cell's activities= it "tells" the cell what to do
question
2. What are the similarities and differences between DNA and RNA?
answer
DNA: double stranded, DEOXYRIBOSE sugar, 4 bases (A,T,C,G) RNA: single stranded, RIBOSE sugar, 4 bases (URACIL not T, A, C, G)
question
3. What is a gene?
answer
a section of DNA that codes for a protein that determines a particular trait
question
4. What is a genome? .
answer
the complete set of DNA
question
5. What is DNA called the "blueprint of life"?
answer
It contains instructions for building an organism. It stores the GENETIC CODE for PROTEIN synthesis.
question
6. What is the structure of the DNA molecule?
answer
DOUBLE HELIX of many nucleotides; Backbone contains sugars and phosphates, while the rungs contain the base pairs.
question
7. What are the three components of a nucleotide?
answer
SUGAR, PHOSPHATE, BASE
question
8. What type of bond holds the two sides of the DNA ladder together?
answer
Hydrogen bonds
question
9. What two scientists were credited with the discovery of the DNA structure?
answer
James Watson & Francis Crick
question
10. What happens in the process of DNA replication? Where does it occur? .
answer
Copy of DNA is made in the NUCLEUS: DNA double helix unzips → Copy made from original strand by pairing up the bases → New DNA molecule formed
question
11. What are the two purposes for DNA replication?
answer
Cell Division & Cell Repair
question
12. How is DNA replication a semi-conservative process? .
answer
For each copy of DNA, it is "½ old" & "½ new". Half of the original DNA molecule is saved, or conserved in each new molecule of DNA.
question
13. What is the replicated strand of DNA? CGA TGC CAA GTT
answer
GCT ACG GTT CAA
question
14. What is the Central Dogma of Molecular Biology?
answer
DNA → RNA → protein >the major steps in the transfer of genetic information, from transcription of DNA to RNA to translation of the RNA to protein
question
15. What are the TWO stages in protein synthesis and where does each occur?
answer
1. TRANSCRIPTION → NUCLEUS 2. TRANSLATION → IN CYTOPLASM AT RIBOSOMES
question
16. Why does the DNA sequence that codes for a protein need to be copied onto RNA?
answer
DNA is too big to leave the nucleus. A copy of the gene is made onto mRNA since it is small and can leave the nucleus through the pore.
question
17. What are the steps of transcription? Where does it occur? .
answer
This occurs in the nucleus. ∙DNA partially unzips to expose gene sequence ∙G,U,A,C bases pair up with bases on template DNA ∙mRNA leaves nucleus through pore
question
18. What molecule is made during transcription?
answer
mRNA
question
19 (HONORS 3) What are the steps of translation?
answer
∙Ribosome binds to mRNA at START CODON ∙Codon from mRNA and anticodon from tRNA line up ∙Amino acid gets added to the elongating polypeptide chain ∙Ribosome continues reading until it hits the STOP CODON on the mRNA, then it releases the protein and the mRNA
question
20. How do the three kinds of RNA differ? mRNA, rRNA and tRNA
answer
∙mRNA carries genetic code from DNA to ribosomes ∙rRNA directs translation of mRNA; part of the ribosome ∙tRNA transfers amino acids to the ribosomes where proteins are synthesized THEY ALL MEET AT THE RIBOSOMES TO PARTICIPATE IN PROTEIN SYNTHESIS.
question
21. What are the similarities and differences between codons and anticodons? .
answer
BOTH consist of *3* bases. CODONS are only found on mRNA ONLY 1 ANTICODON is found on a single tRNA; correct amino acid is released when it matches to codon on mRNA
question
22. Every codon on a mRNA codes for _____ amino acid.
answer
Every codon on a mRNA codes for *1* amino acid.
question
23. What is a polypeptide chain of amino acids?
answer
PROTEIN
question
24. What type of bond holds the amino acids together in a protein?
answer
PEPTIDE BONDS
question
25a. For the DNA sequence, GAC CTA AGG TGC, that codes for a protein: What is the transcribed mRNA strand? .
answer
CUG GAU UCC ACG
question
25 b. For the DNA sequence, GAC CTA AGG TGC: What is the sequence of anticodons on the tRNA? .
answer
GAC CUA AGG UGC
question
25 c. For the DNA sequence, GAC CTA AGG TGC: How many amino acids will this protein have?
answer
4 Every CODON codes for 1 Amino Acid. Since there are 4 codons, the protein will have 4 amino acids. Every CODON is made up of 3 bases.
question
HONORS 1. During DNA replication, what enzymes play a key role and what do they do?
answer
HELICASE unwinds helix DNA POLYMERASE adds new nucleotides by matching bases, proofreads new strand DNA LIGASE seals up fragments
question
HONORS 2. What are exons and introns?
answer
EXONS CODE FOR AMINO ACIDS INTRONS DO NOT CONTAIN CODE BOTH found on RNA after transcription occurs. During splicing, introns are removed before mRNA leaves nucleus
question
HONORS 4. How does the ribosome know when to start and stop translation?
answer
During translation, when the ribosome reads the mRNA it begins protein elongation at the INITIATOR (start) CODON. When the ribosome reads the mRNA and it hits the TERMINATOR (Stop) CODON, the protein is complete and translation stops.
