Bms 300 Final Review Quiz
- 1.
Signaling of GnRH to gonadotropes is an example of which of the following:
- A.
Autocrine signaling
- B.
Paracrine signaling
- C.
Neutral signaling
- D.
Endocrine signaling
- E.
Neuroendocrine signaling
Correct Answer
D. Endocrine signalingExplanation
The signaling of GnRH to gonadotropes is an example of endocrine signaling. Endocrine signaling involves the release of hormones into the bloodstream, which then travel to target cells or tissues located at a distance from the source of the hormone. In this case, GnRH is released by the hypothalamus and travels through the bloodstream to the pituitary gland, where it stimulates the release of gonadotropins (FSH and LH) that regulate the function of the gonads.Rate this question:
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- 2.
Which of the following is not released by cells in the anterior pituitary?
- A.
Luteinizing hormone (LH)
- B.
Thyroid stimulating hormone (TSH)
- C.
Oxytocin (OT)
- D.
Growth hormone (GH)
- E.
All of the above are released by cells in the anterior pituitary
Correct Answer
C. Oxytocin (OT)Explanation
Oxytocin (OT) is secreted from the posterior pituitary
The anterior pituitary secretes (LH) (FSH) (Thyroid stimulating hormone TSH) (GH) (ACTH) (Prl)Rate this question:
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- 3.
Intracellular receptors require which of the following domains?
- A.
Transactivation domain, DNA binding domain, hormone binding domain
- B.
Translation domain, DNA binding domain, hormone binding domain
- C.
Transactivation domain, mitochondrial binding domain, hormone binding domain
- D.
Transactivation domain, DNA binding domain, mitochondrial binding domain
- E.
Membrane binding domain, translation domain, nuclear binding domain
Correct Answer
A. Transactivation domain, DNA binding domain, hormone binding domainExplanation
It could not be translation because that is mRNA -> amino acids
It does not bind eo the mitochondria and it must be able to bind to DNARate this question:
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- 4.
The insulin receptor is a type of cell surface receptor that is activated by phosphorylation after ligand binding. Specifically, the amino acid that is activated by a ______ is _______.
- A.
Kinase; tyrosine
- B.
Phosphatase; tyrosine
- C.
Kinase; insulin
- D.
Phosphatase; insulin
- E.
None of the above
Correct Answer
A. Kinase; tyrosineExplanation
Kinase adds PO4 which activates an amino acid
Phosphatase removes PO4 which inactivates the amino acid
Insulin is not an amino acidRate this question:
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- 5.
Which of the following combinations or statements is INCORRECT?
- A.
GnRH binds cell surface receptors on gonadotropes for release of gonadotropins, which bind cell surface receptors on the gonads
- B.
Estradiol binds primarily to cell surface receptors
- C.
Transcription of protein hormones occurs in the nucleus
- D.
The Pre-prohormone sequence for GnRH is necessary for "signaling" or "localization" information to direct transport
- E.
Intracellular receptors bind small, lipid soluble hormones and can be found in the cytoplasm or nucleus of a cell
Correct Answer
B. Estradiol binds primarily to cell surface receptorsExplanation
Estradiol is a steroid hormone which is lipid soluble and binds to intracellular receptorsRate this question:
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- 6.
Which of the following hormones is incorrectly paired with its site of action?
- A.
LH: ovaries, testes
- B.
Parathyroid hormone: bone
- C.
Aldosterone: kidney
- D.
Anti-diurectic hormone (ADH/vasopressin):kidney
- E.
Adrenocorticotropic hormone (ACTH): adrenal medulla
Correct Answer
E. Adrenocorticotropic hormone (ACTH): adrenal medullaExplanation
The correct answer is adrenocorticotropic hormone (ACTH): adrenal medulla. ACTH is actually produced by the anterior pituitary gland and acts on the adrenal cortex, not the adrenal medulla. The adrenal medulla is primarily responsible for producing and releasing epinephrine and norepinephrine, which are regulated by the sympathetic nervous system. ACTH, on the other hand, stimulates the adrenal cortex to produce and release cortisol, which is involved in regulating metabolism, immune response, and stress response.Rate this question:
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- 7.
Which of the following is NOT a second messenger used as a method of signal amplification for the cell surface receptors with 7 transmembrane domains, termed G-protein coupled receptors (GPCRs)?
- A.
Cyclic AMP (cAMP)
- B.
Diaclgylcerol (DAG)
- C.
Calcium (Ca2+)
- D.
Inositol trisphosphate (IP3)
- E.
All of the above are 2nd messengers
Correct Answer
E. All of the above are 2nd messengersExplanation
G protein coupled receptors (GPCRs) act via G protein complex to activate enzymes, 7 transmembrane domains, and release second messengers (four listed above) for signal amplificationRate this question:
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- 8.
Which of the following hormones signal through cell surface receptors? Pick the most appropriate combination of hormones.
- A.
All GI hormones, pancreatic hormones, hypothalamic releasing hormones, and testosterone
- B.
Calcitonin, Parathyroid hormone (PTH), and ALL GI hormones, pancreatic hormones, and hypothalamic releasing hormones
- C.
Estrogen, Calcitonin, Parathyroid hormone (PTH), and ALL GI hormones
- D.
ALL GI hormones, pancreatic hormones, hypothalamic releasing hormones, and phospholipase
- E.
NONE of the above
Correct Answer
B. Calcitonin, Parathyroid hormone (PTH), and ALL GI hormones, pancreatic hormones, and hypothalamic releasing hormonesExplanation
Testosterone and works through intracellular receptors
Phospolipase is an enzymeRate this question:
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- 9.
Which of the following statements regarding steroid hormones is TRUE?
- A.
All steroid hormones are derived from cholesterol, a 25 carbon structure
- B.
ALL steroid hormones undergo side chain cleavage in the Golgi apparatus
- C.
Enzymatic modification of pregnenalone in each tissue is the rate limiting step of steroid production
- D.
Pregnenalone is the 27 carbon intermediary produced by lateral chain cleavage
- E.
ALL of the above statements are FALSE
Correct Answer
E. ALL of the above statements are FALSEExplanation
Steroid hormones are derived from cholesterol, a 27 carbon structure
Side chain cleavage takes place in the mitochondria
Pregnenalone is a 21 carbon intermediaryRate this question:
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- 10.
Which of the following statements regarding amino acid derived hormones is TRUE?
- A.
Epinephrine is closely related to Thryoxin (T4) as they are both derived from a Tryptophane amino acid.
- B.
Epinephrine, a catecholamine, is made in the adrenal cortex.
- C.
Iodination of and modification of tyrosine occurs in the thyroid gland for production of T3 and T4
- D.
T3 is produced in the Parathyroid gland and the oaddition of the last iodine occurs in the thyroid gland to produce T4
- E.
ALL of the above statements are FALSE
Correct Answer
C. Iodination of and modification of tyrosine occurs in the thyroid gland for production of T3 and T4Explanation
Epinephrine is derived from Tyrosine in the Adrenal medullaRate this question:
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- 11.
RNA polymerase functions as part of _____ to produce ______.
- A.
Translation, protein
- B.
Replication, DNA
- C.
Transcription, RNA
- D.
Translation, RNA
- E.
Transcription, protein
Correct Answer
C. Transcription, RNAExplanation
RNA is not produced from translation
Transcription does not produce protein, but produces RNA
Translation produced Amino Acid chains firstRate this question:
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- 12.
In the anterior pituitary, hormones are translated (in) on:
- A.
The nucleus
- B.
The Golgi apparatus
- C.
Smooth endoplasmic reticulum
- D.
Rough endoplasmic reticulum
- E.
Free ribosomes
Correct Answer
D. Rough endoplasmic reticulumExplanation
In the anterior pituitary, hormones are translated on the rough endoplasmic reticulum. The rough endoplasmic reticulum is responsible for protein synthesis and has ribosomes attached to its surface. These ribosomes translate the genetic information from mRNA into proteins, including hormones. Therefore, the rough endoplasmic reticulum is the site where hormones are synthesized in the anterior pituitary.Rate this question:
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- 13.
Transcription factors bind to _______ to promote _______:
- A.
DNA, DNA synthesis
- B.
RNA, RNA synthesis
- C.
RNA, protein synthesis
- D.
DNA, transcription
- E.
Protein, DNA replication
Correct Answer
D. DNA, transcriptionExplanation
Transcription factors are proteins that bind to specific DNA sequences, known as promoter regions, to promote the process of transcription. Transcription is the synthesis of RNA molecules from DNA templates. Therefore, the correct answer is DNA, transcription, as transcription factors bind to DNA to promote the transcription process.Rate this question:
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- 14.
Following a bad cut in the skin, a scar will often form. A scar is formed by connective tissue cells, which in this case are likely ______ from the _______.
- A.
Epithelial cells, stratum corneum
- B.
Chondrocytes, dermis
- C.
Fibrocytes, dermis
- D.
Epithelial cells, stratum basale
- E.
Fibrocytes, stratum basale
Correct Answer
C. Fibrocytes, dermisExplanation
Chondrocytes are the primary cell of cartilageRate this question:
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- 15.
Two solutions are separated by a membrane that contains only channels permeable to water (aquaporins). The solution in the left-hand compartment contains 50 millimolar NaCl, which dissociates completely, and the right hand compartment contains 100 millimolar urea which is a small, charged molecule that does not dissociate. Which of the following statements is correct?
- A.
Water will not flow because osmotic forces are balanced
- B.
Water will flow from right to left because the osmotic concentration of the NaCl is higher
- C.
Water will flow from left to right because the osmotic concentration of the urea is higher
- D.
Urea will diffuse from right to left
- E.
A and d are correct
Correct Answer
A. Water will not flow because osmotic forces are balancedExplanation
In this scenario, water will not flow because the osmotic forces are balanced. Osmosis occurs when there is a difference in solute concentration across a semipermeable membrane, causing water to move from an area of lower solute concentration to an area of higher solute concentration. However, in this case, the left-hand compartment has a higher solute concentration (50 millimolar NaCl) compared to the right-hand compartment (100 millimolar urea). Since urea is a small, charged molecule that does not dissociate, it does not contribute to the osmotic pressure. Therefore, the osmotic forces are balanced and water will not flow.Rate this question:
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- 16.
During the synthesis of kinesin, _____ catalyzes the formation of _____.
- A.
Messenger RNA, peptide bonds
- B.
Transfer RNA, ionic bonds
- C.
Ribosomal RNA, peptide bonds
- D.
Transfer RNA, peptide bonds
- E.
Ribosomal RNA, hydrogen bonds
Correct Answer
C. Ribosomal RNA, peptide bondsExplanation
During the synthesis of kinesin, ribosomal RNA catalyzes the formation of peptide bonds. Ribosomal RNA is a component of the ribosome, which is the cellular machinery responsible for protein synthesis. It acts as a catalyst, bringing together the amino acids carried by transfer RNA molecules and facilitating the formation of peptide bonds between them. This process ultimately leads to the synthesis of kinesin, a motor protein involved in cellular transport.Rate this question:
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- 17.
Kinesin is a(n) ________ that moves _______ along ______.
- A.
Kinase, vesicles, microtubles
- B.
ATPase, microtubules, actin
- C.
Kinase, vesicles, actin
- D.
ATPase, vesicles, actin
- E.
ATPase, vesicles, microtubules
Correct Answer
E. ATPase, vesicles, microtubulesExplanation
Kinesin is an ATPase that moves vesicles along microtubules.Rate this question:
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- 18.
Keratin, which is found in keratinocytes is a(n):
- A.
Actin complex
- B.
Motor protein
- C.
ATPase
- D.
Intermediate filament protein
- E.
Microtubule binding protein
Correct Answer
D. Intermediate filament proteinExplanation
Keratin is a type of protein that is found in keratinocytes, which are cells that produce keratin. Keratin is known to be an intermediate filament protein, meaning it is a structural protein that provides strength and stability to cells. It forms a network of filaments within cells, contributing to the structure and integrity of various tissues, such as the skin, hair, and nails. Therefore, the correct answer is intermediate filament protein.Rate this question:
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- 19.
Which of the following proteins would be expected to contain a signal peptide?
- A.
A.) actin
- B.
B.) tubulin
- C.
C.) lysosomal proteins
- D.
D.) a calcium channel
- E.
C and d are correct
Correct Answer
E. C and d are correctExplanation
Lysosomal proteins and a calcium channel would be expected to contain a signal peptide. Signal peptides are short amino acid sequences that target proteins to specific cellular compartments, such as the endoplasmic reticulum or the secretory pathway. Lysosomal proteins are targeted to the lysosomes, which are membrane-bound organelles involved in intracellular digestion. A calcium channel is a transmembrane protein that allows the passage of calcium ions across the cell membrane. Both of these proteins require signal peptides to facilitate their proper targeting and localization within the cell.Rate this question:
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- 20.
In comparison to eukaryotes, prokaryotes lack:
- A.
Endoplasmic reticulum
- B.
Ribosomes
- C.
DNA
- D.
RNA
- E.
Protein
Correct Answer
A. Endoplasmic reticulumExplanation
Prokaryotes lack endoplasmic reticulum, which is a membrane-bound organelle found in eukaryotic cells. The endoplasmic reticulum plays a crucial role in protein synthesis, lipid metabolism, and calcium storage. Prokaryotes, on the other hand, do not have a complex internal membrane system like the endoplasmic reticulum. Instead, they have a simpler structure with no membrane-bound organelles. Prokaryotes carry out protein synthesis using ribosomes, have DNA and RNA for genetic information, and produce proteins, but they do not possess an endoplasmic reticulum.Rate this question:
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- 21.
The signal peptide that emerges from the large ribosomal subunit:
- A.
Is composed of hydrophobic amino acids
- B.
Determines that the protein will be synthesized on rough endoplasmic reticulum
- C.
Binds to a signal recognition particle
- D.
Binds to the protein translocator in the endoplasmic reticulum
- E.
All of the above are correct
Correct Answer
E. All of the above are correctExplanation
The signal peptide that emerges from the large ribosomal subunit is composed of hydrophobic amino acids, which allows it to interact with the hydrophobic interior of the endoplasmic reticulum (ER) membrane. This interaction determines that the protein will be synthesized on the rough ER. Additionally, the signal peptide binds to a signal recognition particle (SRP), which helps to target the ribosome to the ER membrane. Once at the ER membrane, the signal peptide binds to the protein translocator, which facilitates the translocation of the growing polypeptide chain into the ER lumen. Therefore, all of the statements are correct.Rate this question:
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- 22.
The ______ comprise the hydrophilic region of biological membranes.
- A.
Phosphate head groups
- B.
Fatty acid side chains
- C.
Carbon to carbon bonds
- D.
Glycerol backbone
- E.
Ester bonds
Correct Answer
A. Phosphate head groupsExplanation
The phosphate head groups are the hydrophilic region of biological membranes. This is because phosphate groups are polar and have a negative charge, making them attracted to water molecules. In biological membranes, the hydrophilic phosphate head groups face towards the aqueous environment, while the hydrophobic fatty acid side chains face inward, creating a barrier that allows the membrane to regulate the passage of molecules. The carbon to carbon bonds, glycerol backbone, and ester bonds are all components of the phospholipids that make up the biological membranes, but they do not specifically comprise the hydrophilic region.Rate this question:
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- 23.
If a tumor is classified as a carcinoma, you can conclude that the tumor originated as a _______ cell.
- A.
Osteocyte
- B.
Epithelial cell
- C.
Chrondrocyte
- D.
Fibrocyte
- E.
A cell in the dermis
Correct Answer
B. Epithelial cellExplanation
If a tumor is classified as a carcinoma, it indicates that the tumor originated from epithelial cells. Carcinomas are a type of cancer that starts in the epithelial tissue, which is the tissue that lines the surfaces and cavities of organs and structures in the body. Epithelial cells are responsible for protecting and covering the body's surfaces, and they can be found in various organs such as the skin, lungs, and digestive system. Therefore, if a tumor is classified as a carcinoma, it implies that it started from epithelial cells.Rate this question:
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- 24.
The role of histones is to:
- A.
Bind to DNA and assist in folding DNA into a chromosome.
- B.
Permit mRNA molecules to fold properly after they are transcribed
- C.
Permit proteins to fold properly in endoplasmic reticulum
- D.
Bind to specific amino acids in the signal sequence
- E.
Escort mRNA molecules through nuclear pores
Correct Answer
A. Bind to DNA and assist in folding DNA into a chromosome.Explanation
Histones are proteins that play a crucial role in DNA packaging. They bind to DNA and help in folding it into a more compact structure called a chromosome. This folding is necessary to fit the long DNA molecule into the nucleus of a cell. By wrapping around the DNA, histones provide support and stability to the chromosome structure. They also play a role in regulating gene expression by controlling access to the DNA. Therefore, the correct answer is that histones bind to DNA and assist in folding it into a chromosome.Rate this question:
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- 25.
Integrins are examples of ________ proteins that connect epithelial cells to ______ in ______.
- A.
Cytoplasmic, keratin filaments, desmosomes
- B.
Transmembrane, one another, desmonsomes
- C.
Extracellular proteins, the basal lamina, hemidesmosomes
- D.
Transmembrane proteins, basal lamina
- E.
Cytoplasmic proteins, basal lamina, hemidesmosomes
Correct Answer
D. Transmembrane proteins, basal laminaExplanation
The integrins, protein plaque and karatin filaments work together to connect the epithelia to the basal lamina in HemidesmosomesRate this question:
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- 26.
Hydrogen bonding between the carbonyl oxygen of one amino acid and the hydrogen on the amine of a nearby amino acid (every 3.6 amino acid to be precise) is responsible for the _____ structure in proteins
- A.
A.) primary
- B.
B.) secondary
- C.
C.) tertiary
- D.
D.) alpha helical
- E.
B and d are correct
Correct Answer
E. B and d are correctExplanation
the alpha helical is one of two parts to the secondary protein structure.
The primary protein structure is the sequence of amino acids
The Teritiary structure is the three dimensional structure of proteinsRate this question:
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- 27.
The three-dimensional shape (tertiary structure) of a protein results largely from the interaction of the _______ with one another or with water.
- A.
Carboxycylic acid groups
- B.
Amine groups
- C.
Peptide bonds
- D.
R groups
- E.
Phosphodiester bond
Correct Answer
D. R groupsExplanation
The three-dimensional shape of a protein is determined by the interaction of its R groups. R groups, also known as side chains, are variable chemical groups attached to the amino acids that make up the protein. These R groups can be hydrophobic, hydrophilic, or charged, and their interactions with each other and with water molecules play a crucial role in folding the protein into its unique tertiary structure. The specific arrangement of R groups determines the protein's function and stability.Rate this question:
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- 28.
The ribose molecules in RNA are linked one to another by:
- A.
A. hydrogen bonds
- B.
B. peptide bonds
- C.
C. phosphodiester bonds
- D.
D. hydrophobic bonds
- E.
B and c are correct
Correct Answer
C. C. phosphodiester bondsExplanation
The ribose molecules in RNA are linked to one another by phosphodiester bonds. These bonds are formed between the phosphate group of one ribose molecule and the hydroxyl group of the adjacent ribose molecule. This linkage creates a sugar-phosphate backbone in RNA, which provides stability to the molecule and allows for the formation of the RNA strand. Hydrogen bonds are involved in base pairing in RNA, while peptide bonds are involved in linking amino acids in proteins. Therefore, the correct answer is c. phosphodiester bonds.Rate this question:
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- 29.
An experiment is performed in which the sequence of bases coding fot the signal peptide is deleted from an mRNA molecule. When this mRNA is expressed, the resulting protein would be expected to be found in the:
- A.
Lysosomes
- B.
Golgi apparatus
- C.
Endoplasmic reticulum
- D.
Cytoplasm
- E.
All except (cytoplasm) are true
Correct Answer
D. CytoplasmExplanation
The signal peptide is responsible for targeting the protein to the endoplasmic reticulum (ER) during protein synthesis. Without the signal peptide, the protein would not be able to enter the ER and therefore would not be processed in the Golgi apparatus or targeted to the lysosomes. Instead, it would remain in the cytoplasm. Therefore, the correct answer is cytoplasm.Rate this question:
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- 30.
Although we have not yet talked about muscle cells in the heart, these cells are connected to one another at sites called intercalated disks. The cell junctions that form junctions that anchor the cells to one another are
- A.
Tight junctions
- B.
Gap junctions
- C.
Hemidesmosomes
- D.
Desmosomes
- E.
Occluding junctions
Correct Answer
D. DesmosomesExplanation
tight junctions: occluding junction block off underlying tissu from lumen
gap junctions: the communicating junction
hemidesmosomes: connect epithelial to the basal laminaRate this question:
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- 31.
In compact bone,
- A.
Collagen fibers provide resistance to lateral shear forces
- B.
Hydroxyapatite (mostly calcium phosphate) provides resistance to compression forces
- C.
Osteons are organized in columns that run parallel to the long axis of the bone
- D.
An osteon contains a central canal occupied by a blood vessel
- E.
All of the above are correct
Correct Answer
E. All of the above are correctExplanation
The given correct answer is "all of the above are correct." This means that all of the statements mentioned in the question are true for compact bone. Collagen fibers do indeed provide resistance to lateral shear forces, hydroxyapatite (mostly calcium phosphate) provides resistance to compression forces, osteons are organized in columns that run parallel to the long axis of the bone, and an osteon contains a central canal occupied by a blood vessel.Rate this question:
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- 32.
Tunicamycin is a drug that prevents the early stages of protein glycosylation. Where would you expect this drug to have its major effect?
- A.
A.) In the nucleus
- B.
B.) In the ribosome
- C.
C.) In the cytoplasm
- D.
D.) In the endoplasmic reticulum
- E.
B and c are correct
Correct Answer
D. D.) In the endoplasmic reticulumExplanation
Glycosylation is adding sugar molecules to the protein and occurs in the Endoplasmic reticulumRate this question:
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- 33.
Elastin, which is found in connective tissue is an example of:
- A.
Cytoplasmic proteins
- B.
Transmembrane proteins
- C.
Lysosomal proteins
- D.
Secreted proteins
- E.
All of the above are correct
Correct Answer
D. Secreted proteinsExplanation
Elastin is not a secreted protein, so you know it cannot be all of the above.Rate this question:
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- 34.
In the capillaries in the brain, you would expect _______ between adjacent endothelial cells to prevent the movement most hydrophobic molecules from the blood into the brain
- A.
A. gap junctions
- B.
B. desmosomes
- C.
C. hemidesmosomes
- D.
D. tight junctions
- E.
C and d are correct
Correct Answer
D. D. tight junctionsExplanation
Tight junctions are the correct answer because they form a barrier between adjacent endothelial cells, preventing the movement of most hydrophobic molecules from the blood into the brain. Tight junctions create a seal between cells, preventing the leakage of substances between them. This is important in the brain capillaries to maintain the blood-brain barrier, which regulates the transport of molecules and protects the brain from potentially harmful substances. Gap junctions, desmosomes, and hemidesmosomes do not provide the same level of tight sealing and would not be effective in preventing the movement of hydrophobic molecules.Rate this question:
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- 35.
The rope-like extracellular protein that gives skin and fibrocartliage its tough resilient characteristics is:
- A.
Keratin
- B.
Microtubules
- C.
Actin
- D.
Collagen
- E.
Elastin
Correct Answer
D. CollagenExplanation
fibrocartliage is a cartliage and collagen is the major component of cartilageRate this question:
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- 36.
When pathogenic bacteria bind to macrophages, they enter the cell by _______, and travel in vesicles to the _______ where they are destroyed.
- A.
Exocytosis, nucleus
- B.
Exocytosis, lysosomes
- C.
Endocytosis, lysosomes
- D.
Exocytosis, mitochondria
- E.
Endocytosis, mitochondria
Correct Answer
C. Endocytosis, lysosomesExplanation
Pathogenic bacteria enter macrophages through the process of endocytosis. Once inside the cell, they are enclosed in vesicles and transported to the lysosomes. Lysosomes are organelles within the cell that contain enzymes capable of breaking down and destroying the bacteria, thus preventing infection. Exocytosis is the process by which materials are released from the cell, and it does not play a role in the destruction of bacteria within macrophages. Mitochondria are responsible for generating energy in the cell and are not directly involved in the destruction of pathogens.Rate this question:
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- 37.
Which of the following is covalently linked to an amino acid before it enters a ribosome?
- A.
TRNA (transfer RNA)
- B.
MRNA(messenger RNA)
- C.
RRNA (ribosomal RNA)
- D.
The protein transloactor
- E.
The start codon
Correct Answer
A. TRNA (transfer RNA)Explanation
tRNA (transfer RNA) is covalently linked to an amino acid before it enters a ribosome. tRNA molecules have specific binding sites for both amino acids and mRNA. Each tRNA molecule carries a specific amino acid and brings it to the ribosome during protein synthesis. The amino acid is covalently attached to the tRNA molecule through an ester bond, forming an aminoacyl-tRNA. This process is catalyzed by an enzyme called aminoacyl-tRNA synthetase. Once the tRNA with the attached amino acid enters the ribosome, the amino acid is added to the growing polypeptide chain according to the information encoded in the mRNA.Rate this question:
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- 38.
Which of the following BEST describes the difference between exocrine and endocrine
- A.
Exocrine refers to secretion of a substance into the bloodstream
- B.
Endocrine refers to secretion of a neurotransmitter
- C.
Exocrine refers to secretion of a substance into a duct
- D.
Endocrine refers to secretion of a substance into a duct
- E.
Exocrine refers to secretion of a neurotransmitter
Correct Answer
C. Exocrine refers to secretion of a substance into a ductExplanation
Duct systems are exterior systems, exposed to the environment outside of the body. Blood is completely cut off from the outside environment and is therefore an endocrine systemRate this question:
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- 39.
In compact bone, the connective tissue cell type found in concentric rings of the osteon is the:
- A.
Chrondrocyte
- B.
Fibrocyte
- C.
Osteocyte
- D.
Hemotopoietic cell of the spongy bone
- E.
All of the above are correct
Correct Answer
C. OsteocyteExplanation
Chrondrocyte is the cell of the cartilage
fibrocyte is the cell of the dermis is connective tissue properRate this question:
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- 40.
All three types of RNA exit the nucleus through:
- A.
Nuclear pores
- B.
The rough endoplasmic reticulum
- C.
Ribosomes
- D.
The lipid bilayer
- E.
Lysosomes
Correct Answer
A. Nuclear poresExplanation
RNA molecules are synthesized in the nucleus of a cell. In order to perform their functions, they need to exit the nucleus and travel to the cytoplasm where ribosomes are located. The nuclear pores are large protein complexes that act as gateways, allowing molecules to pass in and out of the nucleus. Since RNA molecules need to exit the nucleus, they pass through these nuclear pores to reach the cytoplasm. Therefore, the correct answer is "nuclear pores".Rate this question:
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- 41.
In the peripheral nervous system, the neuronal dendrites and cell bodies are clustered in:
- A.
Nerves
- B.
Ganglia
- C.
Nuclei
- D.
Tracts
- E.
Efferents
Correct Answer
B. GangliaExplanation
In the peripheral nervous system, the neuronal dendrites and cell bodies are clustered in ganglia. Ganglia are small clusters of nerve cells located outside the central nervous system. They serve as relay points for transmitting signals between different parts of the body and the central nervous system. Ganglia play a crucial role in coordinating and regulating various bodily functions, such as sensory perception, motor control, and autonomic functions.Rate this question:
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- 42.
In the central nervous system, which of the following cell types would be expected to have the most active glutamate and K+ uptake mechanisms?
- A.
Astrocytes
- B.
Neurons
- C.
Microglia
- D.
Oligodendrocytes
- E.
Schwann cells
Correct Answer
A. AstrocytesExplanation
Astrocytes are known to have the most active glutamate and K+ uptake mechanisms among the given cell types in the central nervous system. Glutamate is a neurotransmitter that is released by neurons and needs to be cleared from the synaptic cleft to prevent overexcitation. Astrocytes play a crucial role in this process by taking up excess glutamate. Additionally, astrocytes also regulate the extracellular potassium levels by actively taking up potassium ions. Therefore, astrocytes are responsible for maintaining the balance of neurotransmitters and ions in the central nervous system.Rate this question:
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- 43.
Neurons with their cell bodies in the precentral gyrus have their conductile regions in the:
- A.
Ventral horn of the spinal cord
- B.
Spinothalamic tract
- C.
Intermedolateral gray column of the spinal cord
- D.
Dorsal horn of the spinal cord
- E.
Lateral corticospinal tract
Correct Answer
E. Lateral corticospinal tractExplanation
precentral gyrus refers to the portion of the brain before the central sulcus where cell bodies and dendrites of the motor cortex are located.
The first portion of the word is the position of the neuronal cell body (input region) [cortico in this case] the second portion of the word is the position of the output region [spinal in this case]Rate this question:
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- 44.
In lower motor neurons, kinesin and tubulin would be synthesized on ______ in the _________.
- A.
Rough endoplasmic reticulum, axon
- B.
Free ribosomes, cell body
- C.
Rough endoplasmic reticulum, cell body
- D.
Smooth endoplasmic reticulum, axon
- E.
Free ribosomes, axon
Correct Answer
B. Free ribosomes, cell bodyExplanation
In the Nervous system, all protein synthesis occurs in free ribosomes. Ribosomes are located in the cell body only.Rate this question:
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- 45.
The ligand-gated channels activated by a somatic efferent would be found in the:
- A.
A. intermediolateral gray column
- B.
B. skeletal muscle
- C.
C. ventral horn of the spinal cord
- D.
D. sympathetic chain ganglia
- E.
A and d are correct
Correct Answer
B. B. skeletal muscleExplanation
somatic efferent is the voluntary muscle initiation. The ligan-gated channels are always located in the input region (dendrite)Rate this question:
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- 46.
The resting membrane potential results primarily from which of the following channels being open?
- A.
Voltage-gated Ca2+ channel
- B.
Voltage-gated Na+ channel
- C.
Voltage-gated K+ channel
- D.
K+ leak channel
- E.
Both voltage-gated Na+ channel and Voltage-gated K+ channel
Correct Answer
D. K+ leak channelExplanation
The resting membrane potential is the electrical charge difference across the cell membrane when the cell is at rest. This potential is primarily determined by the movement of potassium ions (K+) across the membrane. K+ leak channels allow K+ ions to move out of the cell, contributing to the negative charge inside the cell and the positive charge outside. Therefore, the correct answer is the K+ leak channel.Rate this question:
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- 47.
The movement of membrane proteins in axons occurs in _______ on _______ as fast axoplasmic transport.
- A.
The cytoplasm, rough endoplasmic reticulum
- B.
Vesicles, actin filaments
- C.
The cytoplasm, microtubules
- D.
Vesicles, microtubules
- E.
Vesicles, cytoplasmic proteins
Correct Answer
D. Vesicles, microtubulesExplanation
In axons, the movement of membrane proteins occurs through the transportation of vesicles along microtubules. Microtubules are long, hollow tubes made up of protein subunits called tubulins, which provide a track for the movement of vesicles. Vesicles are small, membrane-bound sacs that transport molecules within the cell. This process is known as fast axoplasmic transport and is essential for the proper functioning and maintenance of axons.Rate this question:
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- 48.
Like myosin in muscle movement, kinesin, which drives fast axoplasmic transport is a(n):
- A.
ATPase
- B.
GTP binding protein
- C.
Ca2+ binding protein
- D.
Kinase
- E.
All of the above are correct
Correct Answer
A. ATPaseExplanation
Kinesin is a motor protein that plays a crucial role in fast axoplasmic transport, which is the movement of cellular components along axons. Like myosin, kinesin also requires energy to function, and this energy is obtained from ATP hydrolysis. Therefore, kinesin is an ATPase, making the answer "ATPase" correct.Rate this question:
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- 49.
In skeletal muscle, you would expect to find ligand-gated ionotropic channels:
- A.
In the sarcoplasmic reticulum
- B.
In the T-tubule membrane
- C.
Confined to the sarcolemma at the neuromuscular synapse
- D.
Along the entire length of the muscle fiber
- E.
In the sarcoplasmic reticulum and along the entire length of the muscle fiber
Correct Answer
C. Confined to the sarcolemma at the neuromuscular synapseExplanation
the Sarcolemma is the plasma membrane of muscle tissueRate this question:
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- 50.
Protein synthesis for primary sensory afferent neurons that carry information about proprioception and fine (discriminative touch) would take place in the:
- A.
Dorsal horn of the spinal cord.
- B.
Thalmus.
- C.
Dorsal column nuclei in the brain stem.
- D.
Cerebral cortex
- E.
Dorsal root ganglion
Correct Answer
E. Dorsal root ganglionExplanation
Protein synthesis occurs on free ribosomes in the nervous system. Ribosomes are located in the cell bodies only. Proprioception and fine touch is the somatosensory and afferent is the ascending neurons. The cell bodies of primary sensory afferent neuros are located in the dorsal root ganglionRate this question:
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Mar 18, 2023Quiz Edited by
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Dec 14, 2010Quiz Created by
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