Meiosis
In which round of meiosis cell division do homologous chromosomes separate?
A. I
B. II
C. III
D. IV
A. Homologous chromosomes separate during the first round of Meiosis.
Meiosis only goes through two rounds of cell division, Meiosis I and Meiosis II. In Meiosis II, sister chromatids separate.
In which direction does DNA polymerase add nucleotides on the lagging strand?
A. 5' to 3'
B. 3' to 5'
C. Multidirectional
D. None of the above
A. 5' to 3'
Where does eukaryotic transcription occur?
A. In the ribosome
B. In the cytoplasm
C. In the nucleus
D. None of the above
C. In the nucleus
What is the 3-nucleotide sequence that codes for a protein in mRNA called?
A. Anticodon
B. Codon
C. Ribosome
D. Intron
Name the tRNA binding sites on a ribosome.
APE.
The binding order is EPA. tRNA binds to the furthest site to the left that is open on a ribosome to accumulate an amino acid chain or a polypeptide.
In which phase of meiosis I does crossing over occur?
A. Telophase
B. Cytokinesis
C. Prophase
D. Metaphase
C. Prophase
Homologous chromosomes (Homologues) condense in prophase, form an overlap (chiasma) between them, and cross over before they align on the equatorial plate of the cell in metaphase I.
What two processes does DNA polymerase initiate to correct DNA replication errors?
Proofreading and Mismatch Repair
Proofreading occurs as DNA polymerase adds nucleotides. If there is an error the enzyme will go back to correct it before completing replication.
Mismatch repair occurs after Replication is completed and errors must be repaired in the DNA sequence.
What must be done before mRNA can leave the nucleus to continue with translation?
The mRNA must be made mature by splicing the introns out of the sequence and adding on a 5' cap (GTP) and a poly a-tail.
What does the codon AUG code for? *You may need the amino acid chart for this question.
AUG is a start codon that codes for Methionine.
The order of amino acids is determined by a ribosome, true or false?
A gene in DNA holds the instructions to make a polypeptide. The amino acids determine what order the amino acids will be made.
Which process increases genetic diversity in eukaryotes?
A. Conjugation
B. Crossing Over
C. Transformation
D. Oogenesis
B. Crossing Over
Crossing over can only happen in eukaryotes because prokaryotes do not carry condensed DNA (chromosomes). Independent Assortment increases diversity as well, which occurs in Metaphase I and II. An increase in genetic diversity in prokaryotes is caused by conjugation.
What are the two things telomeres help in regards to chromosomes and genetic material?
A. They are unnecessary, that is why they are referred to as junk DNA
B. They protect the end of chromosomes and code for proteins.
C. They keep the chromatin from condensing and aid in mismatch repair.
D. They keep the genetic code intact and protect the end of chromosomes.
D. They keep the genetic code intact and protect the end of chromosomes
What is the strand that is used to create mRNA and the strand that is not used in transcription called?
The strand that is used is the template strand. The strand that is not used is the coding strand or non-template strand. The non-template strand is the same sequence as the newly transcribed mRNA because it will match the template strand. The only difference is there will be a U in the place of a T.
Where does eukaryotic translation occur?
A. In the ribosome
B. In the nucleus
C. In the cytoplasm
D. In the codon
A. In the ribosome
Which type of replication is DNA replication?
A. Dispersive
B. Conservative
C. Semi-conservative
D. None of the above
C. Semi-conservative
Describe the process of conjugation between two prokaryotes.
A "donor" prokaryote cell will connect to another prokaryote cell through a conjugation bridge. It will copy its own DNA and send the copy to the other cell through the bridge making the second prokaryote cell the "recipient" prokaryote cell. The "recipient" cell incorporates new DNA into its chromosomes.
Describe the structure of DNA and its two strands.
DNA has a phosphate and sugar backbone and is made up of nucleotide bases held together by phosphodiester bonds. The nucleotides follow Chargaff's Rules of A pairs with T and G pairs with C. It has two strands that form a double helix and that run anti-parallel to each other.
Which enzyme transcribes the template strand and produces mRNA in transcription?
A. DNA polymerase
B. Ligase
C. RNA polymerase
D. Primase
C. RNA polymerase
On tRNA, what is carried on the top and bottom of the RNA?
The top: Amino acid
The bottom: Anticodon
What type of reproduction is meiosis?
Sexual reproduction.
Name the process of Meiosis I and II and briefly describe what happens in each phase.
Metaphase I: Homologues align on the equatorial plate via independent assortment.
Anaphase I: The homologues separate.
Telophase I: The Homologues begin separate into two cells forming a cleavage furrow.
Cytokinesis II: The homologues separate into two complete diploid daughter cells.
Prophase II: The sister chromatids condense.
Metaphase II: Sister chromatids align on the equatorial plate.
Anaphase II: Sister chromatids separate.
Telophase II: The sister chromatids begin to separate into four cells forming cleavage furrows.
Cytokinesis II: The sister chromatids separate completely into 4 haploid daughter cells.
Name each of the enzymes involved in replication with a short description of its function.
Helicase: Unwinds DNA strands
Topoisomerase: Keeps the DNA molecule from over-winding.
Single-Strand Binding Protein: Stabilizes unwound DNA so they do not close during replication.
Primase: Produces RNA primer which gives DNA polymerase a place to start adding nucleotides.
DNA polymerase III: Adds nucleotides by starting at the RNA Primer.
Endonuclease: Removes the RNA primers.
DNA polymerase I: Adds nucleotides to replace the removed primers.
DNA ligase: Catalyzes the phosphodiester bonds to link the Okazaki fragments in the lagging strand.
Explain what occurs in eukaryotic transcription.
The template strand from the DNA molecule is transcribed by RNA polymerase and an mRNA strand the same as the coding strand of DNA is created with uracil instead of thymine. mRNA gets processed into mature RNA by splicing out the introns and adding a 5' cap and a poly-a tail. The processed mRNA exits the nucleus.
Explain what occurs in eukaryotic translation.
The codons in the mRNA are translated by tRNA by the anticodon it carries while it is bonded to the mRNA binding site on the small subunit of the ribosome. That anticodon is complementary to the mRNA codon. It will code for a specific amino acid. That amino acid will be carried by the tRNA that will bind to either of the EPA binding sites on the ribosome. The binding site will release the amino acids in a chain that will form a polypeptide once it folds.
What complex in a pre-replicated DNA molecule begins the replication process.
The origin of replication.