Chapter 2

What links sister chromatids together? A) histones B) chromatins C) centromeres D) dyneins E) actins

During what phase of cell division do two new nuclear envelopes begin to redevelop? A) prophase B) interphase C) telophase D) anaphase E) metaphase

During what phase of cell division do chromosomes align along the midline? A) prophase B) interphase C) telophase D) anaphase E) metaphase

Which of the following is NOT a phase of mitosis? A) meiosis B) prophase C) metaphase D) telophase E) anaphase

During what phase of the cell cycle does rapid protein synthesis occur as the cell grows to double its size. A) G0 B) G1 C) G2 D) S E) mitosis

During what phase of the cell cycle does cellular replication of DNA occur? A) G0 B) G1 C) G2 D) S E) mitosis

During what phase of the cell cycle is the cell carrying out its normal activity and NOT involved directly in cell division? A) G0 B) G1 C) G2 D) S E) mitosis

What are Okazaki fragments? A) sections of RNA prior to splicing B) termination codons C) initiation factors D) sections of DNA formed during replication E) proteins that target other cell proteins for degradation

During replication, which strand of the new DNA is synthesized from the 5' to 3' strand of original DNA? A) beginning strand B) ending strand C) leading strand D) lagging strand E) trailing strand

What is/are the beadlike structure(s) of chromosomes within the nucleus between periods of cell division? A) Histones B) Chromatin C) Chromophore D) Chromatid E) Promoter

What enzyme catalyzes the reaction whereby nucleotides are added to the polynucleotide chain during replication? A) RNA polymerase B) helicase C) DNA polymerase D) histone E) chromatin

Ubiquitin tags proteins for what purpose? A) protect from degradation by proteasomes B) mark for degradation by proteasomes C) for synthesis to continue on the rough endoplasmic reticulum D) for the protein to be secreted by exocytosis E) for the protein to enter the nucleus and alter transcription

What functions as a marker to direct proteins to proteasomes that degrade proteins? A) Protease B) Polymerase C) AUG D) Ubiquitin E) The A site

What organelle packages proteins into secretory vesicles? A) rough endoplasmic reticulum B) smooth endoplasmic reticulum C) Golgi apparatus D) lysosomes E) peroxisomes

When proteins are synthesized by ribosomes on the rough endoplasmic reticulum, where does the translation begin? A) cytosol B) rough endoplasmic reticulum C) smooth endoplasmic reticulum D) nucleus E) Golgi apparatus

Which of the following is NOT a possible destination for proteins synthesized on ribosomes free in the cytosol? A) remains in cytosol B) peroxisome C) mitochondrion D) nucleus E) secreted from the cell

Protein enters the Golgi apparatus ________. A) directly from the smooth endoplasmic reticulum B) from a transport vesicle that enters the trans face of the Golgi apparatus C) from a transport vesicle that enters the cis face of the Golgi apparatus D) after leaving the rough endoplasmic reticulum E) through a diffusive process

Which of the following processes is NOT a post-translational modification that occurs in the endoplasmic reticulum or Golgi apparatus to make proteins functional? A) the removal of the leader sequence B) the cleavage of excess amino acids C) the addition of carbohydrates D) the addition of more amino acids E) the addition of lipids

The leader sequence of a protein that has just been translated functions to ________. A) end translation of a protein B) determine the destination of the protein C) initiate degradation of an incomplete protein D) stimulate translation of a protein E) keep the protein in the cytosol

Which of the following is NOT a function of the initiation factors associated with translation of protein from mRNA? A) They bind to the CAP group at the 5' end. B) They form a complex with small ribosomal subunits. C) They form a complex with charged tRNA. D) They align the first tRNA with the P site on a ribosome. E) They trigger binding of the small ribosomal subunit to AUG.

Post-transcriptional processing adds a(n) ________ to the 3' end of the mRNA molecule. A) poly A tail B) exon C) CAP D) intron E) poly C tail

Post-transcriptional processing adds a(n) ________ to the 5' end of the mRNA molecule. A) poly A tail B) exon C) CAP D) intron E) poly C tail

What is special about the P site of a ribosome? A) It contains the enzyme that catalyzes formation of a peptide bond. B) It has the binding site for mRNA. C) It holds the tRNA with the most recent amino acid that has been added to the polypeptide chain. D) It holds the tRNA with the next amino acid to be added to the polypeptide chain. E) It causes the ribosome to attach to the endoplasmic reticulum.

Following is a list of steps for initiating translation. Put them in the correct order. 1. Binding of initiator tRNA to mRNA 2. Binding of large ribosomal subunit to mRNA 3. Binding of small ribosomal subunit to mRNA 4. Binding of tRNA with 2nd amino acid to the A site 5. Formation of covalent bond between methionine and second amino acid A) 1, 2, 3, 4, 5 B) 1, 3, 2, 4, 5 C) 2, 3, 1, 4, 5 D) 3, 2, 1, 4, 5 E) 3, 1, 2, 4, 5

What is the base sequence of the tRNA molecule that recognizes the complementary mRNA molecule? A) anticodon B) codon C) initiator codon D) P site E) A site

The promoter sequence of the gene is recognized by ________ , which initiates transcription. A) DNA polymerase B) RNA polymerase C) tRNA polymerase D) helicase E) methioninase

A codon is ________. A) a series of three nucleotides found in mRNA that codes for an amino acid B) the sequence of amino acids within a protein C) a monosaccharide linked to a disaccharide D) a phosphate group attached to a base E) a membrane-bound protein that binds hormones

Where does RNA polymerase bind to initiate transcription? A) hormone response element B) initiation factor C) promoter sequence D) leader sequence E) P subunit of the ribosome

Which of the following statements about the genetic code is FALSE? A) mRNA is read 3 bases at a time, which are called codons. B) Each codon is specific for only one amino acid. C) Each amino acid is coded for by only one codon. D) There are 3 termination codons that do not code for amino acids. E) There is one initiator codon that codes for an amino acid.

A mRNA codon is complementary to the DNA ________. A) leader sequence B) promoter sequence C) triplet D) gene E) anticodon

What causes DNA to uncoil during transcription? A) binding of tRNA to the initiator codon B) binding of RNA polymerase to the promoter sequence C) binding of DNA polymerase to the leader sequence D) binding of helicase to the DNA E) binding of ubiquitin to the DN

Which of the following protects mRNA from degradation in the cytosol? A) introns B) exons C) poly A tail D) RNA CAP E) ubiquitin

What is the portion of DNA that codes for a particular protein called? A) nucleotide B) gene C) triplet D) codon E) promoter sequence

During transcription, ________. A) DNA is synthesized from DNA in the nucleus B) RNA is synthesized from DNA in the nucleus C) RNA is synthesized from DNA in the cytoplasm D) protein is synthesized from RNA in the nucleus E) protein is synthesized from RNA in the cytoplasm

RNA polymerase binds to a ________ to initiate the process of ________. A) leader sequence : translation B) leader sequence : transcription C) gene : translation D) promoter sequence : transcription E) triplet : translation

The strand of DNA that gets transcribed to mRNA is called the ________. A) intron strand B) exon strand C) ribophorin D) sense strand E) promoter sequence

Which of the following statements about the genetic code is true? A) A single gene contains only those nucleotides that code for a single protein. B) Termination codons do not code for amino acids. C) The tRNA anticodon is complementary to the mRNA codon, and therefore is ALWAYS identical to the DNA triplet word. D) The promoter sequence is found on the antisense strand of DNA. E) A single codon may code for more than one amino acid.

What strand of mRNA would be transcribed from the following strand of DNA: AATG? A) TTUC B) TTAC C) UUGT D) UUAC E) GGUA

The initiator codon, that originates transcription, codes for the amino acid ________. A) proline B) methionine C) arginine D) leucine E) tyrosine

The initiator codon is composed of the sequence ________. A) CCG B) CCC C) UUG D) AUG E) AAC

Based upon the triplet nature of a codon and the presence of four possible bases, how many possible amino acids might be coded for by mRNA? A) 8 B) 16 C) 32 D) 64 E) 128

During translation, ________ is synthesized in the ________. A) DNA : nucleus B) RNA : nucleus C) protein : nucleus D) RNA : cytoplasm E) protein : cytoplasm

The process whereby a complementary mRNA is produced from a DNA template is called ________. A) translation B) post-translational modification C) transcytosis D) transcription E) transoperon

Which of the following does NOT describe a part of post-transcriptional processing? A) capping of the 5' end B) removal of the introns from the strand C) addition of a poly A tail at the 3' end D) formation of bonds between a phosphate group and a sugar E) splicing of nucleic acid fragments

Intercellular communication can occur through the binding of a chemical released from one cell to a specific ________ on another cell. A) receptor B) organelle C) nucleus D) clathrin-coated vesicle E) phagosome

What type of junction would you expect to find most commonly in the intestinal tract, where exchange across epithelium is common? A) tight junctions B) loose junctions C) gap junctions D) I junctions E) desmosomes

In some cases, signals originating within one cell can diffuse directly to a neighboring cell through ________. A) desmosomes B) cadherins C) gap junctions D) tight junctions E) occludins

________ are proteins that form channels between cells, allowing ions and small molecules to diffuse directly from one cell to the other. A) Connexins B) Cadherins C) Dyneins D) Occludins E) Tubulins

________ are proteins attached to intermediate filaments in regions where cells are exposed to mechanical stresses. A) Connexins B) Cadherins C) Dyneins D) Occludins E) Tubulins

________ are proteins that fuse adjacent cells together to form a nearly impermeable barrier. A) Connexins B) Cadherins C) Syneins D) Occludins E) Tubulins

The protein ________ is responsible for generating force as microtubular proteins slide past one another. A) tubulin B) dynein C) myosin D) actin E) keratin

Which microtubular proteins are responsible for the distribution of chromosomes during cell division? A) tubulin B) spindle fibers C) actin D) myosin E) keratin

Which of the following filaments is found in cilia and flagella? A) microfilaments only B) intermediate filaments only C) microtubules only D) microfilaments and microtubules E) microfilaments and intermediate filaments

Keratin is an example of which type of cytoskeletal protein? A) microfilaments B) intermediate filaments C) microtubules D) centrioles E) tight junctions

Which cytoskeletal proteins provide the structural support for microvilli? A) microfilaments B) intermediate filaments C) microtubules D) centrioles E) tight junctions

Which of the following is NOT a function of the cytoskeleton? A) cellular movement B) contraction C) mechanical support D) suspension of organelles E) cellular metabolism

Which of the organelles contains its own DNA? A) mitochondria B) lysosomes C) rough endoplasmic reticulum D) smooth endoplasmic reticulum E) Golgi apparatus

Which of the following statements about ribosomes is FALSE? A) Ribosomes contain protein. B) Ribosomes contain ribosomal RNA. C) Ribosomes are the site of protein synthesis. D) Ribosomes can be located free in the cytosol. E) Ribosomes can be located in the Golgi apparatus.

________ are membrane-bound organelles that contain enzymes like catalase, which catalyzes the breakdown of H2O2 to H2O and O2. A) Lysosomes B) Peroxisomes C) Ribosomes D) Mitochondria E) Vaults

________ are membrane-bound organelles containing enzymes that degrade cellular and extracellular debris. A) Lysosomes B) Mitochondria C) Peroxisomes D) Ribosomes E) Vaults

What organelle synthesizes most of the ATP used by cells? A) lysosomes B) peroxisomes C) ribosomes D) mitochondria E) Golgi apparatus

Which of the following statements is true? A) The compositions of the intracellular fluid and extracellular fluid are identical due to the free movement of molecules across the cell membrane. B) The nuclear envelope is continuous with the membrane of the endoplasmic reticulum. C) The Golgi apparatus contains the enzyme catalase to break down the hydrogen peroxide it produces when degrading oxygen-derived wastes. D) Proteins to be secreted from the cell are synthesized in the mitochondrial matrix. E) Ribosomes are composed of protein and lipid.

In the liver, detoxifying enzymes are localized in what organelle? A) lysosomes B) peroxisomes C) smooth endoplasmic reticulum D) Golgi apparatus E) mitochondria

Which of the following is an INCORRECT description of the function of the organelle? A) ATP synthesis occurs in the mitochondria. B) Peptide hormone synthesis occurs in the rough endoplasmic reticulum. C) Breakdown of phagocytosed debris occurs in the peroxisomes. D) Packaging of secretory products into vesicles occurs in the Golgi apparatus. E) Calcium is stored in the smooth endoplasmic reticulum.

Which of the following organelles is specialized for lipid and steroid synthesis? A) rough endoplasmic reticulum B) smooth endoplasmic reticulum C) mitochondria D) lysosomes E) peroxisomes

Which of the following is NOT a property of smooth endoplasmic reticulum? A) steroid hormone synthesis B) stores calcium C) in liver cells, it contains detoxifying enzymes D) forms transport vesicles to move proteins to the Golgi apparatus E) contains the enzyme catalase

What organelle packages and directs proteins to their proper destination? A) ribosomes B) smooth endoplasmic reticulum C) rough endoplasmic reticulum D) Golgi apparatus E) lysosomes

Where are triglycerides synthesized? A) cytosol B) mitochondria C) rough endoplasmic reticulum D) smooth endoplasmic reticulum E) Golgi apparatus

The ________ is the site where lipids, triglycerides, and steroids are synthesized, as well as where calcium is stored within the cell. A) rough endoplasmic reticulum B) smooth endoplasmic reticulum C) mitochondria D) lysosome E) nucleolus

Continuous with the outer portion of the nuclear pore, this membrane-bound structure functions in the synthesis of secretory proteins, integral membrane proteins, or proteins bound for other organelles. A) rough endoplasmic reticulum B) smooth endoplasmic reticulum C) mitochondria D) lysosome E) nucleolus

Lipophobic molecules that are to be released by cells are stored in membrane-bound structures called ________. A) secretory vesicles B) inclusions C) the Golgi apparatus D) excretory vesicles E) the endoplasmic reticulum

Where inside a cell is glycogen stored? A) mitochondria B) lysosomes C) cytosol D) Golgi apparatus E) smooth endoplasmic reticulum

Where is the genetic code stored? A) brain B) heart C) nucleus D) Golgi apparatus E) cytoplasm

The ________ is the site of ribosomal RNA production. A) nucleus B) nucleolus C) mitochondria D) cytosol E) lysosome

The layer of carbohydrates on the external surface of a cell is called what? A) inclusion B) glycocalyx C) glycogen D) glycolipid E) desmosome

Which of the following is NOT an amphipathic molecule? A) phospholipid B) integral membrane protein C) glycolipid D) glucose E) connexon

Which of the following is an amphipathic molecule? A) peripheral membrane protein B) integral membrane protein C) glycogen D) glucose E) triglyceride

Which of the following is NOT an integral membrane protein? A) carrier proteins for mediated transport B) connexons C) channels for ion diffusion across membranes D) occludins E) actin

Which of the following components of the plasma membrane forms ion channels? A) phospholipids B) cholesterol C) carbohydrates D) integral membrane proteins E) peripheral membrane proteins

Which of the following is NOT found in plasma membranes? A) proteins B) eicosanoids C) cholesterol D) carbohydrates E) phospholipids

The presence of ________ in the plasma membrane can increase the fluidity of the membrane. A) cholesterol B) integral membrane proteins C) peripheral membrane proteins D) glycoprotein E) phospholipids

________ is composed of nucleotide polymers with the phosphate of one nucleotide bound to the ribose sugar of another. A) Ribonucleic acid B) Deoxyribonucleic acid C) Guanosine monophosphate D) Adenosine diphosphate E) Flavin adenine dinucleotide