Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
495 Cards in this Set
- Front
- Back
|
Which type of osteogenesis imperfecta is fatal in utero?
|
Type II
|
|
|
Rb and p53 tumor suppressors prevent which transition in the cell cycle?
|
Transition from G1 to S phase; defective cells are not allowed to undergo DNA synthesis
|
|
|
How are cilia structurally composed?
|
Nine microtubule doublets around two central microtubules
|
|
|
Desmin stains identify which type of cells
|
Muscle
|
|
|
What type of collagen is disrupted in Alport's syndrome?
|
Type IV collagen
|
|
|
What type of collagen is found in the nucleus pulposus, the jelly-like substance in the middle of the spinal disc?
|
Type II
|
|
|
Cilia, flagella, mitotic spindles, neurons and centrioles are all composed of which cytoskeletal element?
|
Microtubule
|
|
|
What drug that is used to treat gout acts on microtubules?
|
Colchicine
|
|
|
What type of collagen is found in the skin and fascia?
|
Type I
|
|
|
What type of collagen is found in the connective tissue of the uterus?
|
Type III
|
|
|
Are microtubules involved in fast or slow transport along the neuronal axons?
|
Slow axoplasmic transport
|
|
|
During which phase of the cell cycle can a cell enter G0?
|
G1
|
|
|
What is the incidence of osteogenesis imperfecta?
|
1:10,000
|
|
|
Approximately what percent of the plasma membrane is composed of phospholipids?
|
50.00%
|
|
|
What type of collagen is found in bone?
|
Type I
|
|
|
What is the function of fibrillin?
|
It acts as a scaffold for tropoelastin
|
|
|
What are the six steps of collagen synthesis in order?
|
Synthesis, hydroxylation, glycosylation, exocytosis, proteolytic processing, cross-linking
|
|
|
True or False: Proteoglycans get assembled from their component core proteins in the Golgi apparatus.
|
TRUE
|
|
|
A child seen in the emergency room is found to have multiple healing fractures of different ages. What disease should be ruled out before filing abuse charges against the parents?
|
Osteogenesis imperfecta
|
|
|
Name four cellular structures in which microtubules are found.
|
Cilia, flagella, mitotic spindle, centrioles
|
|
|
What type of inheritance does osteogenesis imperfecta show?
|
Autosomal dominant
|
|
|
Name four examples of labile cells
|
Labile cells (bone marrow, gut epithelium, skin, and hair follicles)
|
|
|
Which phase of the cell cycle is usually the shortest?
|
Mitosis
|
|
|
Neurons, skeletal and cardiac muscle, and red blood cells are examples of _____ (permanent/stable/labile) cells.
|
Permanent
|
|
|
A single-collagen α chain during collagen synthesis is referred to as what?
|
Preprocollagen
|
|
|
In patients with I-cell disease, the failure to add mannose-6-phosphate to proteins in the Golgi apparatus leads to what deficit?
|
There is no signal that targets lysosomal enzymes to the lysosome, resulting in exocytosis of the enzymes
|
|
|
What type of collagen is found in the basement membrane?
|
Type IV
|
|
|
A baby is born with multiple fractures and hearing loss. What finding is expected during the ophthalmologic examination?
|
Blue sclerae
|
|
|
Where does collagen synthesis occur in the cell?
|
In the rough endoplasmic reticulum
|
|
|
A triple helix that is composed of three collagen α chains with the terminal regions cleaved off is referred to as what?
|
Tropocollagen
|
|
|
What effect does the inhibition of the Na+-;K+ adenosine triphosphatase by digoxin have on cardiac contractility?
|
It increases cardiac contractility by increasing intracellular calcium concentration
|
|
|
Vimentin, desmin, cytokeratin, glial fibrillary acid proteins, and neurofilaments are all examples of which type of cytoskeletal element?
|
Intermediate filaments
|
|
|
What type of collagen is found in teeth?
|
Type I, which is found in dentin
|
|
|
What is the histologic term for rough endoplasmic reticulum in neurons? What substances are synthesized there?
|
Nissl bodies, which are the site of enzyme (such as ChAT) and neuropeptide synthesis
|
|
|
Clathrin is a protein that transports vesicles from the trans face of the Golgi apparatus to where?
|
Clathrin directs from trans-golgi to lysosomes and from plasma membrane to endosome
|
|
|
What is the basic pathophysiologic defect in patients with I-cell disease?
|
The failure of the addition of mannose-6-phosphate to lysosomal proteins and the resulting pathological exocytosis of enzymes
|
|
|
Microtubules are formed from what two protein building blocks?
|
α-Tubulin and β-tubulin
|
|
|
A triple helix composed of three collagen α chains that has not yet been cleaved is referred to as what?
|
Procollagen
|
|
|
What organ (other than the kidneys and the ears) can be affected in Alport's syndrome
|
This disease may result in ocular lesions
|
|
|
What is the effect on melting temperature if the content of cholesterol in the plasma membrane is increased?
|
The melting temperature increases
|
|
|
What is the typical inheritance pattern of Alport's syndrome?
|
X-linked recessive
|
|
|
Is tropocollagen formed intracellularly or extracellularly?
|
Extracellularly
|
|
|
List three places to which the Golgi apparatus sends proteins and lipids.
|
The plasma membrane, lysosomes, and secretory vesicles
|
|
|
What is the name of the enzyme that covalently cross-links lysine residues to hydroxylysine residues?
|
Lysyl oxidase
|
|
|
What are the symptoms seen in Chédiak-Higashi syndrome?
|
Pyogenic infections, partial albinism, and peripheral neuropathy
|
|
|
Hepatocytes and lymphocytes are examples of _____ (permanent/stable/labile) cells .
|
Stable
|
|
|
You are seeing a man who has progressive deafness and renal failure. The other males in his family show the same symptoms; what is the likely diagnosis?
|
Alport's syndrome, which is typified by progressive hereditary nephritis and deafness
|
|
|
An -OH group is added to _____ and _____ after translation of the collagen α chain.
|
Proline; lysine
|
|
|
What protein is responsible for anterograde transport on the microtubule?
|
Kinesin
|
|
|
What protein is responsible for retrograde transport on the microtubule?
|
Dynein
|
|
|
What syndrome results from a defect in the dynein arm of cilia?
|
Kartagener's syndrome
|
|
|
What syndrome results from a microtubule polymerization defect that leads to impaired lysosomal emptying and poor phagocytosis
|
Chediak-Higashi syndrome
|
|
|
The conversion of preprocollagen to procollagen requires what process?
|
Glycosylation
|
|
|
What protein causes the movement of the cilia?
|
Axonemal dynein is an adenosine triphosphatase that causes bending of the cilium
|
|
|
List the four main phases of mitosis in order
|
Prophase, metaphase, anaphase, and telophase
|
|
|
Neurofilament stains identify which type of cells?
|
Neurons
|
|
|
Permanent and stable cells are typically in which phase of the cell cycle?
|
G0
|
|
|
Which two cytoskeletal elements are necessary for muscle contraction and cytokinesis?
|
Actin and myosin
|
|
|
Many staggered tropocollagen molecules with covalent lysine-hydroxylysine cross-links are referred to as _____ _____.
|
Collagen fibrils
|
|
|
What is the role of coat protein I in vesicular trafficking?
|
Retrograde movement from the Golgi apparatus to the endoplasmic reticulum
|
|
|
True or False? Microtubule filaments grow rapidly but collapse slowly.
|
False; they grow slowly and collapse quickly
|
|
|
When does DNA synthesis occur in the cell cycle?
|
After G1 and before G2 in the cell cycle
|
|
|
The dental imperfections seen in osteogenesis imperfecta is due to lack of _____ in the teeth?
|
Dentin
|
|
|
Na+-K+ adenosine triphosphatase exchanges how many sodium and potassium ions in each cycle?
|
Three sodium ions out and two potassium ions in per cycle
|
|
|
What is the most abundant type of collagen
|
Type I
|
|
|
Which vitamin is required for the hydroxylation of proline and lysine in collagen?
|
Vitamin C
|
|
|
List the three components of interphase.
|
G1, S phase, and G2
|
|
|
What anticancer drug used to treat breast cancers stabilizes microtubules?
|
Paclitaxel
|
|
|
When does mitosis occur in the cell cycle?
|
Mitosis occurs after G2 and before G1 in the cell cycle
|
|
|
What are the main functions of the rough endoplasmic reticulum?
|
The synthesis of secretory (exported) proteins and the addition of N-linked oligosaccharides to proteins
|
|
|
A young woman with blue sclerae also has hearing loss. What is the pathophysiology of her hearing loss?
|
Abnormal bones of the middle ear
|
|
|
How many adenosine triphosphates are consumed in one cycle of the Na/K pump?
|
One
|
|
|
Elastin is rich in which two amino acids? Are they glycosylated or nonglycosylated?
|
Proline and lysine; nonglycosylated
|
|
|
What happens to cell cycling when there is a mutation in a tumor suppressor such as Rb or p53?
|
There is unrestrained growth in the cell, and thus an increased likelihood to develop a malignancy
|
|
|
Vimentin stains identify which type of cells
|
Connective tissue
|
|
|
What type of protein-bound saccharides is modified in the Golgi apparatus?
|
N-oligosaccharides (on asparagine)
|
|
|
Approximately what percent of the plasma membrane is composed of cholesterol?
|
50.00%
|
|
|
Give two examples of cells that are rich in smooth endoplasmic reticulum.
|
Liver hepatocytes and steroid-hormone-producing cells of the adrenal cortex
|
|
|
What is the common etiology of the blue sclerae and multiple fractures seen in osteogenesis imperfecta?
|
Both symptoms are due to a loss of normal functioning type I collagen; the blue sclerae result from decreased connective tissue over the choroid in the eye, whereas multiple fractures result from decreased collagen in the bone matrix
|
|
|
What type of collagen is found in the vitreous body, the clear gel that fills the space between the lens and the retina?
|
Type II
|
|
|
The Golgi apparatus functions as the distribution center for what?
|
Synthesized proteins and lipids
|
|
|
Does the formation of tropocollagen from the cleavage of procollagen increase or decrease its solubility?
|
Decreases; tropocollagen is insoluble.
|
|
|
What is the effect of high cholesterol content on the fluidity of a cell membrane?
|
Fluidity is decreased
|
|
|
Where does ouabain bind to the Na+-K+ adenosine triphosphatase?
|
At the K+ binding site
|
|
|
What form of collagen is exocytosed from the cell into the extracellular space?
|
Procollagen
|
|
|
A child presents with coarse facial features, clouded corneas, restricted joint movement, and high plasma levels of lysosomal enzymes. What could this patient have?
|
I-cell disease
|
|
|
Which phase of the cell cycle is shortened in rapidly dividing cells?
|
G1
|
|
|
_____ (Permanent/stable/labile) cells enter G1 from G0 when stimulated.
|
Stable
|
|
|
_____ (Permanent/stable/labile) cells remain in G0 and regenerate from stem cells.
|
Permanent
|
|
|
Ehlers-Danlos syndrome is associated with what defects of the vasculature of the brain
|
Berry aneurysms
|
|
|
Which diagnosis should you consider in a male with infertility, bronchiectasis and recurrent sinusitis?
|
Kartagener's syndrome
|
|
|
Name two types of cells that are rich in rough endoplasmic reticulum.
|
Goblet cells (secrete mucus) and plasma cells (secrete antibodies)
|
|
|
During wound healing, type ____ collagen is laid down first as part of granulation tissue. Then, type ____ collagen is produced as part of late wound healing.
|
III; I
|
|
|
_____ (Free/Attached) ribosomes synthesize cytosolic and organellar proteins, whereas _____ (free/attached) ribosomes synthesize secretory proteins.
|
Free; attached
|
|
|
How are serine and threonine residues modified in the golgi?
|
O-oligosaccharides are added
|
|
|
What is a stretchy protein found within lungs, large arteries, elastic ligaments, vocal cords and ligamenta flava (which connect the vertebrae)?
|
Elastin
|
|
|
What is the relationship between cyclin-dependent kinases and cyclins?
|
Cyclins are regulatory proteins that are translated and activate cyclin-dependent kinases at appropriate times in the cell cycle
|
|
|
Which two anticancer drugs alter the polymerization of microtubules?
|
Vincristine and vinblastine
|
|
|
Excess elastase activity can result in what lung disorder?
|
Emphysema: α1-antitrypsin inhibits elastase, which degrades elastin; therefore, a lack of α1-antitrypsin can leads to the loss of elastin in the lungs, thereby resulting in emphysema
|
|
|
What enzyme is inhibited by α1-antitrypsin
|
α1-Antitrypsin inhibits elastase, which degrades elastin
|
|
|
Glial fibrillary acid protein stains identify which type of cells?
|
Neuroglia
|
|
|
What type of collagen is found in blood vessels?
|
Type III
|
|
|
Cytokeratin stains identify which type of cells
|
Epithelial cells
|
|
|
What type of collagen is most frequently affected in Ehlers-Danlos syndrome?
|
Type III collagen (reticulin)
|
|
|
True or False? All types of Ehlers-Danlos syndrome are transmitted through an autosomal recessive inheritance pattern.
|
False; Ehlers-Danlos syndrome shows variable inheritance, depending on the type
|
|
|
What antifungal agent targets microtubules
|
Griseofulvin
|
|
|
British sailors in the 17th century come to you due to an inability to hydroxylate proline and lysine residues for collagen synthesis. What disease do they have, and why do you prescribe limes?
|
Scurvy, and the limes will supply them with the vitamin C they are deficient in during their long voyage (and earn them the nickname, "limeys")
|
|
|
What is another name for type III collagen
|
Reticulin (reticular means net-like)
|
|
|
What type of collagen predominates in fetal tissue?
|
Type III
|
|
|
How are tyrosine residues modified in the Golgi?
|
Sulfation
|
|
|
List two functions of the smooth endoplasmic reticulum.
|
Steroid synthesis and the detoxification of drugs and poisons
|
|
|
What antihelminthic drugs target microtubules?
|
Mebendazole and thiabendazole
|
|
|
What type of collagen is found in hyaline cartilage?
|
Type II
|
|
|
True or False? Kartagener's syndrome causes only male infertility.
|
False; Kartagener's syndrome causes infertility in both sexes
|
|
|
Osteogenesis imperfecta is a defect in what process?
|
Type I collagen synthesis
|
|
|
Why might patients with Ehlers-Danlos syndrome have an increased risk of organ rupture?
|
Poor type III collagen synthesis results in weak connective tissue
|
|
|
The golgi adds which marker to proteins to target them to lysosomes?
|
Mannose-6-phosphate
|
|
|
How does inhibition of Na+-K+ exchange result in increased cardiac contractility?
|
There is indirect inhibition of Na+-Ca2+ exchange, which results in increased intracellular Ca2+ concentration
|
|
|
Microvilli and adhering junctions are composed of which two cytoskeletal elements?
|
Actin and myosin
|
|
|
What disease results in an inability to form procollagen from pro α chains?
|
Osteogenesis imperfecta
|
|
|
Which amino acids predominate in collagen
|
Glycine, proline, hydroxyproline, and hydroxylysine
|
|
|
What is the underlying cellular malfunction that leads to Kartagener's syndrome?
|
Immotile cilia as a result of a dynein arm defect
|
|
|
What is the role of coat protein II in vesicular trafficking?
|
Anterograde transport of rough endoplasmic reticulum to the cis-Golgi
|
|
|
Marfan's syndrome is caused by a defect in what protein?
|
Fibrillin
|
|
|
How are proteoglycans modified in the Golgi
|
Sulfation
|
|
|
A 22-year-old female presents with history of recurrent pneumonia. Subsequent chest x-ray reveals dextrocardia. What is the most likely diagnosis involving these two findings?
|
Kartagener's syndrome
|
|
|
Ehlers-Danlos syndrome is a defect of what process?
|
Collagen synthesis
|
|
|
What is the name of the process by which clathrin transports vesicles from outside the cell to inside the cell through fusion of the two lipid-based membranes?
|
Receptor-mediated endocytosis
|
|
|
A patient presents with hyperextensible skin, easy bruising, and hypermobile joints. What is the most likely diagnosis?
|
Ehlers-Danlos syndrome
|
|
|
What type of collagen is found on the articular surface of joints?
|
Type II
|
|
|
What type of collagen is found in the cornea
|
Type I
|
|
|
_____ (Permanent/stable/labile) cells never go to G0 and divide rapidly with a short G1.
|
Labile
|
|
|
What is the relationship between Alport's syndrome and Goodpasture's syndrome?
|
Both are diseases of type IV collagen (Alport's is genetic; Goodpasture's is autoimmune)
|
|
|
What pharmacologic agent blocks the transport of acetylcholine into the presynaptic vesicles in nerve terminals?
|
Vesamicol
|
|
|
What is the mode of inheritance of hemochromatosis?
|
Autosomal recessive
|
|
|
Neurofibromatosis type 1 (von Recklinghausen's disease) is associated with a mutation on which chromosome?
|
Chromosome 17 (remember: there are 17 letters in "von Recklinghausen")
|
|
|
What is the mode of inheritance of hereditary spherocytosis?
|
Autosomal dominant
|
|
|
What is the mode of inheritance in a family in which a disease is transmitted only through the mother and all children (both boys and girls) are affected?
|
Mitochondrial inheritance
|
|
|
A patient has an extreme friendliness towards strangers and cheerful disposition, with noted mental retardation and cardiovascular disease; what is the diagnosis?
|
Williams syndrome
|
|
|
At the paravertebral ganglia, the neurotransmitter _____ acts on _____ receptors to mediate sympathetic nervous system function.
|
Acetylcholine; nicotinic acetylcholine
|
|
|
Which types of receptors are activated by norepinephrine?
|
α1- and α2-; β1-receptors (with lower affinity)
|
|
|
Isoproterenol is an agonist for which receptors?
|
β1- and β2-receptors equally
|
|
|
To what class of G-proteins are D2-receptors linked?
|
i
|
|
|
What are the signs of Angelman's syndrome
|
Mental retardation, seizures, ataxia, and inappropriate laughter (happy puppet syndrome)
|
|
|
What role does dopamine have in treating shock?
|
Increases blood pressure while maintaining renal perfusion
|
|
|
True or False? 22q11 Syndromes are associated with hypercalcemia.
|
False; 22q11 syndromes are associated with hypocalcemia due to parathyroid aplasia
|
|
|
How does the use of β-blockers affect the progression of congestive heart failure?
|
Slows progression of heart failure; β-blockers reduce cardiac output but have proven benefit in congestive heart failure
|
|
|
Patients with Williams syndrome typically have _____ (coarse/masked/elfin) facies.
|
Elfin
|
|
|
Why should β-blockers be used with caution in diabetic patients?
|
β-Blockers should be used with caution in diabetic patients because they can block initial warning signs of hypoglycemia such as increased heart rate and diaphoresis
|
|
|
The symptoms of organophosphate poisoning are caused by the inhibition of what enzyme
|
Acetylcholinesterase
|
|
|
What neurotransmitter receptor mediates parasympathetic tone in the smooth muscle
|
Muscarinic acetylcholine receptors (specifically, M3)
|
|
|
The two types of chromosomal inversions are called _______ and _____inversions.
|
Pericentric and paracentric
|
|
|
In refractory cases, how can you cure hereditary spherocytosis?
|
A splenectomy is curative
|
|
|
How is muscular dystrophy diagnosed?
|
Biopsy of skeletal muscle and elevated creatine phosphokinase
|
|
|
Phospholipase C catalyzes the cleavage of membrane lipids into what molecules?
|
Inositol trisphosphate3 and diacylglycerol
|
|
|
What effect does the activation of α2-receptors in presynaptic sympathetic nerve terminals have on norepinephrine release?
|
It inhibits norepinephrine release
|
|
|
Metaproterenol, albuterol, salmeterol, and terbutaline are agonists for which receptors
|
β2-receptors > β1-receptors
|
|
|
What is the pattern of inheritance of Wiskott-Aldrich syndrome?
|
-linked recessive (remember: Be Wise, Fool's GOLD Heeds False Hope; Wiskott-Aldrich)
|
|
|
What are some effects of β-blocker toxicity
|
Bradycardia, atrioventricular block, congestive heart failure (reduced cardiac output), sedation, sleep alteration, impotence, exacerbation of asthma
|
|
|
True or False? A mother may pass a disease with a mitochondrial pattern of inheritance to both her sons and her daughters.
|
TRUE
|
|
|
What is the effect of atropine on the airway mucosa?
|
It decreases secretions
|
|
|
What is the pathophysiology of Duchenne's muscular dystrophy?
|
Dystrophin anchors muscle fibers in the membrane and lack of the protein leads to accelerated muscle breakdown
|
|
|
Define Lyonization
|
The random inactivation of one X chromosome in females
|
|
|
What final effector enzyme is activated by receptors that are coupled with Gs proteins
|
Protein kinase A
|
|
|
Ninety percent of cases of adult polycystic kidney disease are associated with a mutation in what gene?
|
APKD1, which is located on chromosome 16 (remember: 16 letters in "polycystic kidney")
|
|
|
What effect does neostigmine have on the central nervous system?
|
None; it does not penetrate the blood-brain barrier (remember: NEO CNS = NO CNS)
|
|
|
What are three effects of α2-selective blocker toxicity?
|
Sedation, increased serum cholesterol, increased appetite
|
|
|
What neurotransmitter mediates sympathetic tone in the renal vascular smooth muscle?
|
Dopamine
|
|
|
What disease is caused by microdeletions at 22q11 and involves defects of the thymus, the parathyroid, and the heart?
|
DiGeorge syndrome
|
|
|
What are the clinical features of trisomy 18
|
Mental retardation, rocker-bottom feet, micrognathia, low-set ears, clenched hands, prominent occiput, congenital heart disease
|
|
|
What is the significance of imprinting in genetic diseases?
|
A genetic disease has a different phenotype depending on whether the mutation is inherited from the mother or from the father
|
|
|
What is the mode of inheritance of familial hypercholesterolemia?
|
Autosomal dominant
|
|
|
What is the mechanism and clinical application for benztropine?
|
It is a muscarinic antagonist used to reduce symptoms of Parkinson's disease
|
|
|
What neurotransmitter receptor mediates parasympathetic tone in the cardiac muscle
|
Muscarinic acetylcholine receptors (specifically, M2)
|
|
|
To what class of G-proteins are α1-receptors linked?
|
q
|
|
|
What is the mechanism and clinical application for scopolamine?
|
It is a muscarinic antagonist used to treat motion sickness
|
|
|
You recently prescribed haloperidol to your patient to treat his schizophrenia, but he has since developed Parkinson's-like motor adverse effects. What drug could you add to his regimen to treat this?
|
Benztropine
|
|
|
Would you use phenoxybenzamine or phentolamine before removal of a pheochromocytoma? Why?
|
Phenoxybenzamine, because it is irreversible. Phentolamine is reversible, so the high levels of catecholamines released during surgery would overcome the α-block
|
|
|
What two direct agonist cholinomimetic drugs can be used to treat glaucoma?
|
Carbachol and pilocarpine
|
|
|
True or False? Phenylephrine can be used to treat nasal congestion.
|
TRUE
|
|
|
True or False? The Hardy-Weinberg law assumes that there are no mutations at the locus being studied.
|
TRUE
|
|
|
What is the pattern of inheritance of ocular albinism?
|
-linked recessive (remember: Be Wise, Fool's GOLD Heeds False Hope; Ocular albinism)
|
|
|
What is the mechanism of β-blockers in the treatment of glaucoma?
|
They reduce the secretion of aqueous humor, reducing intraocular pressure
|
|
|
What effect does D1-receptor activation have on renal vasculature?
|
It relaxes renal vascular smooth muscle
|
|
|
By what mechanism does ephedrine exert its sympathomimetic effect?
|
It stimulates the release of stored catecholamines
|
|
|
What toxin inhibits the calcium-induced release of acetylcholine from the cholinergic nerve terminals?
|
Botulinum
|
|
|
What is the effect of increased inositol triphosphate on the intracellular concentration of calcium?
|
It increases the intracellular calcium concentration
|
|
|
You are performing an autopsy on a man who had Huntington's disease; what would you find on inspection of the brain?
|
Huntington's disease is associated with atrophy of the caudate
|
|
|
What is the pattern of inheritance of hemophilia A and B?
|
-linked recessive (remember: Be Wise, Fool's GOLD Heeds False Hope; Hemophilia A)
|
|
|
True or False? Marfan's syndrome is associated with hyperflexible joints.
|
TRUE
|
|
|
What are the signs of Prader-Willi syndrome
|
Mental retardation, obesity, hypogonadism, and hypotonia
|
|
|
Which trisomy is the most common: 13, 18, or 21? What is the least common?
|
21 (1:700); 13 (1:15,000)
|
|
|
In what muscle group does weakness normally begin in patients with Duchenne's muscular dystrophy?
|
The pelvic girdle muscles
|
|
|
True or False? Preganglionic sympathetic axons synapse on neurons in the peripheral ganglia.
|
False; preganglionic sympathetic axons synapse on neurons in the paravertebral ganglia
|
|
|
Why is it important to give pralidoxime as well as atropine in organophosphate poisoning
|
Because organophosphates are irreversible inhibitors of acetylcholinesterase and pralidoxime helps to regenerate functional acetylcholinesterase
|
|
|
Neurofibromatosis type 2 is a result of a mutation in the gene _____ found on chromosome _____.
|
NF2, 22 (remember: Type 2 = 22)
|
|
|
What effect does M2-receptor activation have on cardiac function?
|
It decreases heart rate and contractility
|
|
|
What is the prognosis for a patient with familial adenomatous polyposis?
|
Adenomatous polyps will progress to colon cancer unless they are resected
|
|
|
Does a Robertsonian translocation always result in a loss of genetic material?
|
A balanced translocation retains all genetic material and will not have any abnormal phenotype; if the translocation is unbalanced, genetic material is lost and abnormalities result
|
|
|
What type of acetylcholine receptors does hexamethonium antagonize?
|
Nicotinic acetylcholine receptors
|
|
|
What is the significance of a dominant negative mutation?
|
A nonfunctional altered protein that also prevents the normal gene product from functioning
|
|
|
What is the mode of inheritance for neurofibromatosis type 2?
|
Autosomal dominant
|
|
|
What is the pattern of inheritance of fragile X syndrome?
|
-linked recessive (remember: Be Wise, Fool's GOLD Heeds False Hope; Fragile X)
|
|
|
In general, are autosomal dominant or autosomal-recessive disorders more severe
|
Autosomal recessive
|
|
|
In chromosomal inversions, _____ (pericentric/paracentric) inversion involves the centromere and proceeds through meiosis
|
Pericentric
|
|
|
How is Prader-Willi syndrome inherited?
|
It is inherited via the deactivation of paternal copies of genes on chromosome 15
|
|
|
A patient has café-au-lait spots, Lisch nodules, scoliosis, neural tumors, and pheochromocytoma. What is the most likely diagnosis?
|
Neurofibromatosis type 1 (von Recklinghausen's disease)
|
|
|
Amphetamine, ephedrine, and cocaine are (direct/indirect) sympathomimetics.
|
Indirect
|
|
|
How do acrosomal chromosomes align to create a Robertsonian translocation?
|
The long arms match up and fuse at the centromere, losing the short arms of the chromosomes
|
|
|
Cystic fibrosis results from a defect in which gene? Which chromosome? Which ion channel
|
CFTR; 7; chloride
|
|
|
True or False? Atropine toxicity can cause fecal incontinence.
|
False; atropine toxicity causes constipation, not fecal incontinence
|
|
|
What makes chromosomes 13, 14, 15, 21, and 22 candidates for Robertsonian translocations
|
They are acrosomal chromosomes, which means that the centromere is located near one end rather than in the middle
|
|
|
What is the pattern of inheritance of Duchenne's muscular dystrophy?
|
-linked recessive (remember: Be Wise, Fool's GOLD Heeds False Hope; Duchene)
|
|
|
What is the major function of β2-receptor activation on the respiratory system?
|
Bronchodilation
|
|
|
What is meant by linkage disequilibrium?
|
Measured in a population, it is the tendency for certain alleles at two linked loci to occur together more often than expected by chance
|
|
|
Where are M1-receptors located?
|
The central nervous system
|
|
|
What is the mechanism of action of bethanechol?
|
Bethanechol is a direct cholinergic agonist resistant to acetylcholinesterase that works on receptors in the bowel and bladder
|
|
|
What is the likelihood of a 20-year-old woman having a baby with Down syndrome? A 45-year-old woman?
|
1:1500; 1:25
|
|
|
Which two adverse effects of atropine are more common in elderly patients?
|
Urinary retention and acute angle closure glaucoma
|
|
|
Which β-blocker is the shortest acting?
|
Esmolol
|
|
|
Approximately what percentage of individuals with von Hippel-Lindau disease will develop bilateral renal cell carcinomas?
|
50.00%
|
|
|
The defect that leads to Huntington's disease is found on chromosome ____.
|
4 (remember: Hunting 4 food)
|
|
|
What β-blocker is frequently used to treat glaucoma?
|
Timolol
|
|
|
Patients with cystic fibrosis characteristically have mucus plugs that disturb the function of which three organs?
|
The pancreas, the lungs, and the liver
|
|
|
What triplet is expanded in fragile X syndrome and what is the result of this repeat?
|
CGG; abnormal methylation of the FMR1 gene
|
|
|
What is the prognosis for a patient with trisomy 18?
|
Death within the first year of life
|
|
|
In Hardy-Weinberg population genetics, what do "p" and "q" represent?
|
Alleles of a gene
|
|
|
What is the clinical application and mechanism of action of phenoxybenzamine?
|
Phenoxybenzamine is a nonselective α-blocker that is used to treat pheochromocytoma
|
|
|
What is the pattern of inheritance of glucose-6-phosphate dehydrogenase deficiency?
|
-linked recessive (remember: Be Wise, Fool's GOLD Heeds False Hope; Glucose-6-phosphate dehydrogenase)
|
|
|
Name five β1-selective antagonists.
|
Acebutolol, Betaxolol, Esmolol, Atenolol, Metoprolol (remember: A BEAM of β1-blockers)
|
|
|
In Leber's hereditary optic neuropathy, vision loss is _____ (central/peripheral).
|
Central
|
|
|
True or False? Hunter's syndrome has the same pattern of inheritance as Hurler's syndrome.
|
False; Hunter's syndrome has X-linked recessive inheritance, whereas Hurler's syndrome has autosomal-recessive inheritance
|
|
|
What is the other name for trisomy 18?
|
Edwards' syndrome (remember: Election age = 18)
|
|
|
A patient has multiple telangiectasias, skin discolorations, and notes recurrent epistaxis; what other physical finding might be expected?
|
This constellation of symptoms is typical of hereditary hemorrhagic telangiectasia; can also see arteriovenous malformations
|
|
|
What is the most common lethal genetic disease among Caucasians?
|
Cystic fibrosis
|
|
|
A newborn has microphthalmia, microcephaly, cleft lip, cleft palate, and polydactyly. What is the most likely diagnosis?
|
Patau's syndrome (trisomy 13)
|
|
|
What is the mechanism and clinical application for pirenzepine?
|
It is a muscarinic antagonist used to treat peptic ulcers
|
|
|
What is the clinical indication for use of echothiophate?
|
The treatment of glaucoma
|
|
|
Do patients with dominant or recessive diseases generally present at a younger age
|
Autosomal-recessive diseases
|
|
|
Huntington's disease has a _____ repeat, while Friedreich's ataxia is a repeat of _____ nucleotides.
|
CAG; GAA
|
|
|
Describe the clinical manifestations of hereditary spherocytosis.
|
Symptoms associated with anemia such as fatigue, shortness of breath, pallor, and dark urine
|
|
|
What is the mode of inheritance of most mucopolysaccharidoses?
|
Autosomal recessive
|
|
|
What is the mode of inheritance of albinism
|
Autosomal recessive
|
|
|
What are two nonselective α- and β-antagonists?
|
Carvedilol, labetalol
|
|
|
According to the mnemonic DUMBBELSS, what four major physiologic processes are blocked by atropine?
|
Diarrhea, Urination, Miosis, Bronchospasm, Bradycardia, Excitation of skeletal muscle, Lacrimation, Sweating, and Salivation
|
|
|
What is the pattern of inheritance of Bruton's agammaglobulinemia?
|
-linked recessive (remember: Be Wise, Fool's GOLD Heeds False Hope; Bruton's agammaglobulinemia)
|
|
|
What are the major functions of β1-receptor activation?
|
It increases heart rate and contractility, increases renin release from the kidneys, and increases lipolysis of adipose tissue
|
|
|
A 50-year-old man has hematuria, hypertension, and progressive renal failure. His kidneys are both massively dilated as a result of multiple large cysts. What is the most likely diagnosis?
|
Autosomal-dominant polycystic kidney disease
|
|
|
What is the pattern of inheritance of Lesch-Nyhan syndrome?
|
-linked recessive (remember: Be Wise, Fool's GOLD Heeds False Hope; Lesch-Nyhan)
|
|
|
What are the major functions of α2-receptor activation?
|
It decreases sympathetic outflow and decreases insulin release
|
|
|
Dopamine is _____ (ionotropic/not ionotropic) and _____ (chronotropic/not chronotropic), while dobutamine is _____ (ionotropic/not ionotropic) and _____ (chronotropic/not chronotropic).
|
Ionotropic; chronotropic; ionotropic; not chronotropic
|
|
|
What is a methacholine challenge test?
|
A test in which methacholine is inhaled to stimulate muscarinic receptors and induce bronchoconstriction to diagnose asthma
|
|
|
What are the four assumptions of the Hardy-Weinberg equation?
|
No mutation occurring at the locus; no selection for any of the genotypes at the locus; completely random mating; no migration
|
|
|
True or False? Slower heart rate is a sign of atropine toxicity.
|
False; heart rate would be increased
|
|
|
What effect does hexamethonium have on heart rate?
|
It can prevent bradycardia in response to increased blood pressure when pressors are given
|
|
|
What organ other than skeletal muscle is affected in Duchenne's muscular dystrophy
|
Heart
|
|
|
Most sphingolipidoses are inherited in a(n) _____-_____ pattern, except for _____ _____.
|
Autosomal-recessive, Fabry's disease
|
|
|
Pralidoxime is used as an antidote for what kind of poisoning? By what mechanism does it accomplish this?
|
Organophosphate/cholinesterase inhibitor poisoning; it regenerates active acetylcholinesterase
|
|
|
What is the clinical application and mechanism of action of phentolamine?
|
Phentolamine is a nonselective α-blocker that is used to treat pheochromocytoma
|
|
|
What is another name for neurofibromatosis type 1?
|
von Recklinghausen's disease
|
|
|
What is the effect of V2-receptor activation? Where are they located?
|
It increases water permeability and reabsorption in the collecting tubules of the kidney
|
|
|
How many syndromes are considered "multiple endocrine neoplasias"?
|
Three, known as MEN I, MEN II, and MEN III
|
|
|
Variable expression of mitochondrial diseases can be accounted for by what phenomenon
|
Heteroplasmy
|
|
|
In chromosomal inversions, _____ (pericentric/paracentric) inversion does not involve the centromere and does not proceed through meiosis.
|
Paracentric
|
|
|
The deletion of the short arm of chromosome 5 leads to what disease?
|
Cri-du-chat syndrome
|
|
|
To what class of G-proteins are V2-receptors linked?
|
s
|
|
|
The symptoms of parathion poisoning are caused by the inhibition of what enzyme?
|
Acetylcholinesterase
|
|
|
What is the effect of atropine on gastrointestinal motility?
|
It decreases motility
|
|
|
What are three clinical applications of ephedrine?
|
To treat nasal congestion, urinary incontinence, and hypotension
|
|
|
Name 5 findings associated with 22q11 deletion syndromes.
|
Cleft palate, Abnormal facies, Thymic aplasia, Cardiac defects, Hypocalcemia (remember: CATCH-22)
|
|
|
True or False? An unbalanced Robertsonian translocation may cause a chromosomal imbalance, but rarely miscarriage or stillbirth
|
False; unbalanced translocations may result in miscarriage, stillbirth, or chromosomal imbalance such as Down or Patau's syndrome
|
|
|
What is the mechanism and clinical application for propantheline?
|
It is a muscarinic antagonist used to treat peptic ulcers
|
|
|
A patient with a history of Graves' disease (hyperthyroidism) presents with chest pain. Her resting heart rate is 128 beats per minute, her blood pressure is 120/80 mmHg, and her respiratory rate is 18 breaths per minute. You order thyroid-stimulating hormone and thyroxine tests. What class of drugs would address her cardiac problems while you await the lab results?
|
ß-Blockers, such as propranolol, will reduce heart rate and consequently reduce angina
|
|
|
To what class of G-proteins are D1-receptors linked?
|
s
|
|
|
What is the mode of inheritance of Huntington's disease?
|
Autosomal dominant
|
|
|
What would you expect to see on urinalysis in a patient with hypophosphatemic rickets?
|
You would expect an increased urine phosphate level since there is proximal tubule phosphate loss
|
|
|
True or False? Newborns with trisomy 13 and newborns with trisomy 18 have similar expected life spans.
|
True; infants with both of these conditions are expected to die before the age of 1 year
|
|
|
What are the clinical manifestations of cri-du-chat syndrome?
|
Microcephaly, moderate to severe mental retardation, high-pitched crying/mewing, epicanthal folds, cardiac abnormalities
|
|
|
Name five nonselective β-blockers.
|
Propranolol, timolol, nadolol, pindolol, and labetalol
|
|
|
True or False? Increased body temperature is a sign of atropine toxicity.
|
True (ie, "hot as a hare")
|
|
|
Which types of receptors are activated by epinephrine?
|
α1-, α2-, β1-, and β2-receptors
|
|
|
Which muscarinic antagonist can be used to reduce urgency in patients with mild cystitis
|
Oxybutynin (also glycopyrrolate)
|
|
|
Dopamine is an agonist for which receptors
|
β1- and β2-receptors
|
|
|
What is the mode of inheritance of sickle cell disease?
|
Autosomal recessive
|
|
|
What aspect of the dystrophin gene makes it particularly susceptible to mutation?
|
The dystrophin gene (DMD) is the largest known human gene, which allows a high rate of spontaneous mutations
|
|
|
What are the clinical manifestations of trisomy 13?
|
Severe mental retardation, rocker-bottom feet, microphthalmia, microcephaly, cleft lip/palate, holoprosencephaly, polydactyly, congenital heart disease
|
|
|
What is the mode of inheritance of Marfan's syndrome?
|
Autosomal dominant
|
|
|
What is the mechanism of β-blockers in the treatment of supraventricular tachycardia?
|
They decrease atrioventricular conduction velocity
|
|
|
Is the effect of isoproterenol on β-receptors greater than, equal to, or less than its effect on α-receptors?
|
Greater than
|
|
|
To what class of G-proteins are H2-receptors linked?
|
s
|
|
|
What are three effects of α1-selective blocker toxicity?
|
Orthostatic hypotension (first dose only), dizziness, headache
|
|
|
Why does norepinephrine administration result in reflex bradycardia?
|
Norepinephrine raises blood pressure, causing a vagal response that leads to reflex bradycardia via increased parasympathetic input to the heart
|
|
|
What is true of genetic diseases with variable expression?
|
The nature and severity of the phenotype varies from one individual to another with the same disease
|
|
|
What effect does β2-receptor activation have on glucagon release?
|
It increases glucagon release
|
|
|
By what mechanism does cocaine exert its sympathomimetic effect?
|
It inhibits catecholamine uptake in the nerve terminal
|
|
|
What are the dermatologic findings in neurofibromatosis type 1?
|
Café au lait spots and axillary freckling
|
|
|
What is the pattern of inheritance of Fabry's disease?
|
-linked recessive (remember: Be Wise, Fool's GOLD Heeds False Hope; Fabry's)
|
|
|
What disease is caused by a microdeletion of the long arm of chromosome 7?
|
Williams syndrome
|
|
|
True or False? X-linked recessive diseases are commonly more severe in males than in females.
|
TRUE
|
|
|
The life expectancy for patients with trisomy 21 is _____ (<1 year/20-40 years/45-50 years).
|
45-50 years
|
|
|
What effect does the activation of angiotensin II receptors in presynaptic sympathetic nerve terminals have on norepinephrine release?
|
It stimulates norepinephrine release
|
|
|
Name 5 endocrine organs that develop tumors in the multiple endocrine neoplasia syndromes.
|
Pancreas, pituitary, parathyroid, thyroid, and adrenal medulla
|
|
|
To what class of G-proteins are M1-receptors linked?
|
q
|
|
|
What enzyme is inhibited directly downstream of Gi-coupled receptors?
|
Adenyl cyclase
|
|
|
To what class of G-proteins are β1-receptors linked?
|
s
|
|
|
From which regions of the central nervous system do sympathetic nerves originate?
|
Thoracic and lumbar regions
|
|
|
Adenyl cyclase catalyzes the conversion of adenosine triphosphate into what molecule
|
cAMP
|
|
|
In spite of their mental retardation, in which cognitive area are patients with Williams syndrome typically advanced?
|
Patients with Williams syndrome typically have well-developed verbal skills
|
|
|
What final effector enzyme is inhibited by receptors that are coupled with Gi proteins
|
Protein kinase A
|
|
|
What pharmacologic agent blocks the conversion of tyrosine to DOPA?
|
Metyrosine
|
|
|
What antidote can be given to a patient who presents with diarrhea, urinary incontinence, miosis, bronchospasm, bradycardia, lacrimation, sweating, and salivation?
|
Atropine and pralidoxime
|
|
|
What is the mode of inheritance in a family in which 50% of sons are affected and there is no male-to-male transmission?
|
X-linked recessive
|
|
|
How is Angelman syndrome inherited?
|
Via the deactivation of the maternal copies of genes on chromosome 15; via chromosomal deletion, faulty imprinting, or uniparental disomy
|
|
|
Describe the clinical manifestations of achondroplasia.
|
Patient has dwarfism with short limbs but a normally sized head and trunk
|
|
|
What type of atrial septal defect is most common in patients with Down syndrome?
|
Septum-primum type
|
|
|
To which class of antiarrhythmic agents do β-blockers belong?
|
Class II; drugs that slow atrioventricular conduction
|
|
|
What five types of receptors are coupled with Gq proteins?
|
α1, M1, M3, H1, and V1
|
|
|
True or False? Pilocarpine is susceptible to acetylcholinesterase.
|
False; pilocarpine is resistant to acetylcholinesterase
|
|
|
What is the pattern of inheritance of Leber's hereditary optic neuropathy?
|
Mitochondrial inheritance
|
|
|
A patient has inherited a mutation in a tumor suppressor gene. Mutation of the remaining (previously normal) copy of the tumor suppressor gene represents a loss of _____, which may lead to the development of cancer
|
Heterozygosity; the patient was previously a heterozygote for lost tumor suppressor gene and both genes must be lost for oncogenesis
|
|
|
A patient has bilateral acoustic neuroma, optic pathway gliomas, and juvenile cataracts. What is the most likely diagnosis?
|
Neurofibromatosis type 2
|
|
|
True or False? All patients who inherit the gene in tuberous sclerosis will display very similar signs and symptoms.
|
False; although autosomal dominant, this disease has incomplete penetrance and a variable presentation
|
|
|
What three types of receptors are coupled with Gi proteins?
|
a2, M2, and D2
|
|
|
A 4-year-old boy with Duchenne's muscular dystrophy has hypertrophied calf muscles; what is the expected strength in his legs?
|
This is actually pseudohypertrophy due to fibrofatty replacement of the muscle and you would expect muscle weakness
|
|
|
True or False? Fragile X syndrome is associated with chromosomal breakage.
|
TRUE
|
|
|
A patient has a flat facial profile, prominent epicanthal folds, and a simian crease. This patient also has mental retardation. What is the most likely diagnosis?
|
Down syndrome
|
|
|
What is the clinical application of bethanechol?
|
Treatment of postoperative and neurogenic ileus and urinary retention (remember: Beth Anne, call (bethanechol) me if you want to activate your Bowels and Bladder)
|
|
|
Why is pyridostigmine used to treat myasthenia gravis?
|
It increases the amount of acetylcholine in the neuromuscular synapse, thereby increasing muscle strength
|
|
|
The defect that leads to familial adenomatous polyposis is found in the ____ gene.
|
APC (remember, it stands for Adenomatosis Polyposis Coli)
|
|
|
A patient with cystic fibrosis is at increased risk for the deficiency of what four vitamins
|
Vitamins A, D, E, and K, all of which are fat soluble
|
|
|
What is the name of the phenomenon whereby a genetic disease has an earlier onset or worsening severity in each subsequent generation?
|
Anticipation
|
|
|
Which two pathogens are the most likely to cause recurrent pulmonary infections in a patient with cystic fibrosis?
|
Pseudomonas species and Staphylococcus aureus
|
|
|
What are the clinical applications of epinephrine?
|
Anaphylaxis, open-angle glaucoma, asthma, hypotension
|
|
|
True or False? 22q11 Syndromes are associated with B cell deficiency.
|
False; 22q11 syndromes are associated with T lymphocyte deficiency due to thymic aplasia
|
|
|
A newborn is diagnosed with Down syndrome. He has a heart murmur on examination. What is the most likely cause?
|
Atrial septal defect
|
|
|
What is the mode of inheritance of the thalassemias?
|
Autosomal recessive
|
|
|
What would a genetic analysis of a patient with Huntington's disease demonstrate on chromosome 4?
|
Trinucleotide repeats of (CAG)n in the Huntingtin gene
|
|
|
How does a chromosomal inversion modify the affected chromosome?
|
It reverses one segment of the chromosome end-to-end
|
|
|
In patients with familial hypercholesterolemia, heterozygotes can be expected to have a cholesterol level around ____ mg/dL, and homozygotes can be expected to have a cholesterol level around ____ mg/dL.
|
300; 700
|
|
|
Name a disease whose pathogenesis involves loss of heterozygosity.
|
Retinoblastoma
|
|
|
What is the advantage of using a heat-stable DNA polymerase?
|
The polymerase is not denatured by heating and can be reused for multiple cycles of polymerase chain reaction
|
|
|
A middle-aged woman had a myocardial infarction 20 years ago, and has tendon xanthomas on her Achilles tendon. What is the most likely diagnosis?
|
Familial hypercholesterolemia
|
|
|
A male patient with cystic fibrosis asks you whether he will be able to have children; what is your response?
|
Unfortunately, males with cystic fibrosis are infertile due to bilateral absence of the vas deferens
|
|
|
What is a cardiac manifestation of tuberous sclerosis?
|
Cardiac rhabdomyoma
|
|
|
What is the mode of inheritance if a disease is present in many generations and affects both males and females in roughly equal proportions?
|
Autosomal dominant
|
|
|
True or False? In the microarray biology technique, DNA or RNA probes are hybridized to the chip.
|
True; either DNA or RNA probes may be used
|
|
|
Patau's syndrome is also known as trisomy _____.
|
13 (remember: Puberty = 13)
|
|
|
Describe the technique of a Southern blot
|
DNA is run on an electrophoresis gel and transferred to a filter; the DNA on the filter is denatured and exposed to a labeled DNA probe, and then the double-stranded DNA is visualized when the filter is exposed to film
|
|
|
Is the loss of the dystrophin gene in Duchenne's muscular dystrophy the result of frameshift, missense, nonsense, or silent mutations?
|
Frameshift mutation
|
|
|
Cri-du-chat syndrome is caused by a deletion of the _____ arm of chromosome ____.
|
Short; 5
|
|
|
The defect that leads to familial adenomatous polyposis is found on chromosome ____.
|
5 (remember: 5 letters in "polyp")
|
|
|
What is the mode of inheritance of α1 antitrypsin deficiency?
|
Autosomal recessive
|
|
|
Autosomal-dominant polycystic kidney disease is associated with what cardiac pathology
|
Mitral valve prolapse
|
|
|
What is the heterozygote prevalence in a population that is in Hardy-Weinberg equilibrium?
|
2pq
|
|
|
Achondroplasia is the result of a defect in the _____ receptor.
|
Fibroblast growth factor 3
|
|
|
Why do patients with hereditary spherocytosis have elevated mean corpuscular hemoglobin concentration?
|
Red blood cells have less surface area and volume and therefore more concentrated hemoglobin
|
|
|
What parental attributes are associated with achondroplasia?
|
Advanced paternal age
|
|
|
What information would an enzyme-linked immunosorbent assay using a test antibody coupled to a color-generating enzyme give you?
|
It would tell you whether a certain antigen is present in the patient's blood
|
|
|
Regarding model systems, genes can be manipulated at specific development points using an inducible Cre-lox system with what type of promoter?
|
Antibiotic-controlled promoter
|
|
|
Recurrent pulmonary infections in patients with cystic fibrosis result in what pulmonary pathology?
|
Bronchiectasis
|
|
|
Duchenne's muscular dystrophy is caused by a deletion of what gene?
|
The dystrophin gene (remember: Duchenne's = Deleted Dystrophin)
|
|
|
Ninety-five percent of cases of Down syndrome are caused by the _____ of homologous chromosomes during the cell division process of _____.
|
Nondisjunction; meiosis
|
|
|
What is the mode of inheritance of phenylketonuria?
|
Autosomal recessive
|
|
|
What type of genetic material is created by exposing mRNA to reverse transcriptase?
|
cDNA, which lacks introns
|
|
|
True or False? A father with an X-linked dominant disease will pass the disease to all of his daughters but none of his sons.
|
TRUE
|
|
|
What is the most common chromosomal disorder?
|
Down syndrome
|
|
|
What is the inheritance pattern of multiple endocrine neoplasias?
|
These syndromes are inherited in an autosomal dominant fashion
|
|
|
The tendency for certain alleles to be inherited together more often than is expected by chance is called what?
|
Linkage disequilibrium
|
|
|
What is another term for the pigmented iris hamartomas associated with neurofibromatosis?
|
Lisch nodules
|
|
|
Down syndrome is also known as trisomy _____.
|
21 (remember: Drinking age = 21)
|
|
|
Describe the technique of an enzyme-linked immunosorbent assay
|
A test antigen that is labeled with a color-generating enzyme can be used to determine the presence of a specific antibody; if the antibody is present, the solution will have an intense color reaction
|
|
|
A baby has low-set ears, micrognathia, a prominent occiput, rocker bottom feet, and clenched hands. What is the most likely diagnosis?
|
Edwards' syndrome (trisomy 18)
|
|
|
A genetic disease that shows _____ _____ will have mutations at different loci that produce the same phenotype.
|
Locus heterogeneity
|
|
|
At what age do Becker's and Duchenne's muscular dystrophy present?
|
Before the age of 5 years
|
|
|
Where is the gene located in Prader-Willi syndrome? In Angelman's syndrome?
|
Both syndromes are due to inactivation or deletion of genes on chromosome 15
|
|
|
What term describes the situation in which cells in the body have a different genetic makeup?
|
Mosaicism
|
|
|
A mother with achondroplasia is pregnant; assuming that the father does not have this condition, what is the likelihood that her child will also have the disease?
|
50%; achondroplasia is an autosomal-dominant disease
|
|
|
What is the mode of inheritance if a gene is present in a single generation and 25% of the offspring from the same two parents have the disease?
|
Autosomal recessive
|
|
|
What three nonrenal pathologies are associated with autosomal-dominant polycystic kidney disease?
|
Polycystic liver disease, berry aneurysm, and mitral valve prolapse
|
|
|
True or False: Albinism is an example of a genetic disease that demonstrates locus heterogeneity.
|
TRUE
|
|
|
Why is recurrent epistaxis a common finding in Osler-Weber-Rendu syndrome?
|
Malformed blood vessels in the nose can break and cause frequent nosebleeds
|
|
|
Describe the process and purpose of RNA inhibition.
|
The degradation of target mRNA reduces gene expression
|
|
|
What is the mode of inheritance of von Hippel-Lindau disease?
|
Autosomal dominant
|
|
|
What laboratory technique is represented with the acronym FISH??
|
Fluorescent In Situ Hybridization
|
|
|
What does fluorescent in situ hybridization allow researchers to do?
|
Directly visualize the location of a certain protein or gene on a molecular level through a fluorescent probe that binds to a site of interest
|
|
|
What pathology of the cardiovascular system is seen in Marfan's syndrome?
|
Cystic medial necrosis of the aorta, aortic incompetence, and dissecting aortic aneurysms
|
|
|
In polymerase chain reaction, premade _____ are used to anneal to specific DNA sequences that will then be amplified.
|
Primers
|
|
|
What is the diagnostic value of a karyotype
|
It can diagnose chromosomal imbalances
|
|
|
What results in the prenatal quad screen indicate possible Down syndrome?
|
α-fetoprotein, β-human chorionic gonadotropin, estriol, and inhibin A
|
|
|
A patient has hemangioblastomas of the retina and cerebellum, as well as bilateral renal cell carcinoma. What is the most likely diagnosis?
|
von Hippel-Lindau disease
|
|
|
True or False? Enzyme-linked immunosorbent assays test antigen-antibody reactivity.
|
TRUE
|
|
|
Patients with Down syndrome who are more than 35 years old have an increased risk of what neurodegenerative disease?
|
Alzheimer's disease
|
|
|
What are the three steps of DNA cloning in order?
|
Insertion of DNA fragments into bacterial plasmids, cleavage of DNA allowing for insertion, isolation of mRNA to be exposed to reverse transcriptase
|
|
|
An infant with failure to thrive also had meconium ileus as a newborn. What is the most likely diagnosis?
|
Cystic fibrosis
|
|
|
True or False? Neurofibromatosis type 2 is associated with skin findings that are similar to those of neurofibromatosis type 1.
|
False; neurofibromatosis type 2 is not associated with abnormal skin findings
|
|
|
True or False? A mother with an X-linked dominant disease may pass the disease to either her sons or her daughters.
|
TRUE
|
|
|
Describe the process of Sanger DNA sequencing.
|
Dideoxynucleotides halt DNA polymerization at each base, generating sequences of various lengths that encompass the entire original sequence so that the terminated fragments are electrophoresed and the original sequence can be deduced
|
|
|
What tissue can be used to perform a karyotype on a fetus?
|
You can sample either the amniotic fluid or the placental tissue
|
|
|
How does N-acetylcysteine free up mucous plugs?
|
It cleaves the disulfide bonds that connect mucous glycoproteins
|
|
|
Marfan's syndrome is associated with what ocular pathology?
|
Subluxation of the lenses
|
|
|
Is Becker's muscular dystrophy more or less severe than Duchenne's muscular dystrophy
|
Becker's muscular dystrophy is less severe and presents later in life
|
|
|
What is true of genetic diseases with incomplete penetrance?
|
Not all individuals with the mutant genotype will show the complete mutant phenotype
|
|
|
What is a Robertsonian translocation?
|
It is a nonreciprocal translocation of chromosome pairs, such that chromosomes carry genetic information in an uneven manner
|
|
|
Describe the technique of a Northern blot.
|
RNA is run on an electrophoresis gel and transferred to a filter; the RNA on the filter is exposed to a labeled DNA probe, and then the hybrid DNA-RNA molecule is visualized when the filter is exposed to film
|
|
|
Which cells are affected in Leber's hereditary optic neuropathy?
|
There is degeneration of retinal ganglion cells and their axons
|
|
|
What is meant by knock-out and knock-in mice?
|
Knock-out refers to the removal of a gene from a host genome and knock-in refers to the insertion of a gene into a host genome
|
|
|
What embryonic structures are altered in 22q11 syndromes?
|
These syndromes are due to aberrant development of the third and fourth branchial pouches
|
|
|
How can a microarray profile gene expression levels?
|
The microarray scanner can detect relative amounts of complementary binding to probes
|
|
|
What is the mode of inheritance of familial adenomatous polyposis?
|
Autosomal dominant
|
|
|
What are four tissues that can be used for chromosomal analysis?
|
Blood, bone marrow, amniotic fluid, and placental tissue
|
|
|
Which neurotransmitters are most affected by Huntington's disease?
|
Decreased levels of γ-aminobutyric acid and acetylcholine
|
|
|
What distinguishes cDNA from most nuclear DNA?
|
cDNA lacks introns
|
|
|
Which type of enzymes cleave DNA at 4- to 6-bp palindromic sequences in cloning?
|
Restriction enzymes
|
|
|
What disease is caused by microdeletions at 22q11 and involves defects of the palate, the face, and the heart?
|
Velocardiofacial syndrome
|
|
|
What is the mode of inheritance of autosomal-dominant polycystic kidney disease?
|
Autosomal dominant
|
|
|
How is cystic fibrosis diagnosed?
|
High concentrations of chloride ions in the sweat
|
|
|
Name three types of chromosome imbalances that can be seen on a karyotype.
|
Autosomal trisomies, microdeletions, and sex chromosome disorders
|
|
|
Most mucopolysaccharidoses are inherited in a(n) _____-_____ pattern, except for _____ _____.
|
Autosomal-recessive; Hunter's disease
|
|
|
Familial hypercholesterolemia is the result of a defect in what type of receptor?
|
Low-density lipoprotein receptor
|
|
|
Myotonic dystrophy is associated with a _____ (CTG/CGG) repeat, while fragile X syndrome has a _____ (CTG/CGG) repeat.
|
CTG; CGG (remember: myoTonic dystrophy = CTG, fraGile X = CGG)
|
|
|
True or False: A mother with an X-linked dominant disease may pass the disease only to her sons.
|
False; both her sons and her daughters may be affected
|
|
|
What does anticipation refer to in genetic disease?
|
Anticipation involves an increase in disease severity and an earlier age of onset in successive generations
|
|
|
What is the mode of inheritance of neurofibromatosis type 1?
|
Autosomal dominant
|
|
|
What renal findings might distinguish a patient with tuberous sclerosis from a patient with adult polycystic kidney disease ?
|
While both will have renal cysts, tuberous sclerosis is associated with renal angiomyolipomas
|
|
|
Among others, what connective tissue gene is deleted in Williams syndrome?
|
The elastin gene
|
|
|
Describe the technique of using a microarray to detect gene expression levels.
|
Thousands of nucleic acid sequences are arranged in grids on glass or silicon. DNA or RNA probes are hybridized to the chip, and a scanner detects the relative amounts of complementary binding
|
|
|
What enzyme is used in polymerase chain reaction to amplify DNA?
|
Heat-stable DNA polymerase
|
|
|
Targeted insertion or deletion of a gene into the genome of a mouse occurs through which step?
|
Homologous recombination
|
|
|
What are the two most common genetic causes of mental retardation?
|
Down syndrome and fragile X syndrome
|
|
|
A patient has hemolytic anemia, increased mean corpuscular hemoglobin concentration, and spheroid erythrocytes. What is the most likely diagnosis?
|
Hereditary spherocytosis
|
|
|
What physical signs are associated with Marfan's syndrome?
|
Marfan's syndrome is associated with a tall habitus and long, tapering fingers and toes
|
|
|
Describe the difference between enzyme-linked immunosorbent assay techniques used to detect antigens and antibodies.
|
A test antigen labeled with a color-generating enzyme can be used to determine the presence of a specific antibody; a test antibody labeled with a color-generating enzyme can be used to see if a certain antigen is present
|
|
|
How does the mnemonic "SNoW DRoP" help one remember which type of blot is used to detect DNA sequences, RNA sequences, or proteins?
|
Southern = DNA, Northern = RNA, Western = Protein
|
|
|
Following PCR, how can products be separated and analyzed?
|
Agarose gel electrophoresis
|
|
|
True or False? Hypophosphatemic rickets can be treated by vitamin D supplementation.
|
False; this disease is also known as vitamin D-resistant rickets
|
|
|
The prevalence of which type of genetic disease is indicated by q in males and q2 in females in Hardy-Weinberg genetics?
|
X-linked recessive diseases
|
|
|
What is the pathophysiology of von Hippel-Lindau disease?
|
A tumor suppressor is deleted, leading to constitutive expression of hypoxia-inducible factors and an overabundance of vascular growth factors
|
|
|
Which gene mutation causes multiple endocrine neoplasias 2A and 2B?
|
ret gene
|
|
|
What is the mode of inheritance of the glycogen storage diseases?
|
Autosomal recessive
|
|
|
A newborn is diagnosed with Down syndrome. She is vomiting bilious material. What is the most likely cause?
|
Duodenal atresia
|
|
|
Autosomal-recessive patterns of inheritance are often found in diseases caused by defects in _____.
|
Enzymes; as opposed to dominant diseases, which are often caused by faulty structural genes
|
|
|
Autosomal-dominant patterns of inheritance are often found in diseases caused by defects in _____ genes.
|
Structural; as opposed to recessive diseases, which are often caused by faulty enzyme genes
|
|
|
What blot technique detects specific sequences of DNA?
|
Southern blot
|
|
|
In RNA inhibition, dsRNA is synthesized then transfected into human cells where it separates and promotes the degradation of which molecule?
|
Messenger RNA
|
|
|
Name four diseases that result from trinucleotide repeat expansion.
|
Huntington's disease, myotonic dystrophy, Friedreich's ataxia, Fragile X syndrome (remember: Try (trinucleotide) hunting for my fried eggs [X])
|
|
|
The defect that leads to von Hippel-Lindau disease is found on chromosome _____.
|
(remember: Von Hippel-Lindau = 3 words for chromosome 3)
|
|
|
Patients with Down syndrome have an increased risk of what type of leukemia?
|
Acute lymphocytic leukemia
|
|
|
A patient has adenoma sebaceum on his face, ash leaf spots on his trunk, mental retardation, and seizures. What the most likely diagnosis?
|
Tuberous sclerosis
|
|
|
What process compares chromosomes microscopically based on morphology, size, arm-length ratio, and banding pattern?
|
Karyotyping
|
|
|
What is an example of a genetic disease that displays anticipation?
|
Huntington's disease
|
|
|
True or False? 22q11 Syndromes are X-linked recessive and show anticipation.
|
False; 22q11 syndromes are due to microdeletions on chromosome 22 and have variable presentations
|
|
|
What is another name for Osler-Weber-Rendu syndrome?
|
Hereditary hemorrhagic telangiectasia
|
|
|
Why are female carriers of X-linked recessive disorders rarely affected?
|
There is random inactivation of X chromosomes in each cell, a process known as lyonization
|
|
|
What is the mechanism of phosphate wasting in hypophosphatemic rickets?
|
There is increased phosphate wasting at the proximal renal tubule
|
|
|
What percentage of sons of a carrier mother are expected to inherit an X-linked recessive disease?
|
50.00%
|
|
|
Define heteroplasmy.
|
The presence of both normal and mutated mitochondrial DNA, resulting in variable expression in mitochondrial inherited diseases
|
|
|
Describe the technique of a Western blot.
|
Sample protein is separated via gel electrophoresis and transferred to a filter; labeled antibody is used to bind the protein of interest
|
|
|
What is the purpose of using DNA polymerase chain reaction?
|
To amplify the number of copies of DNA fragments
|
|
|
What is the pattern of inheritance of Hunter's syndrome?
|
-linked recessive (remember: Be Wise, Fool's GOLD Heeds False Hope; Hunter's)
|
|
|
Microdeletions at chromosome 22q11 can present as a spectrum of diseases including which two recognized syndromes?
|
DiGeorge syndrome or velocardiofacial syndrome
|
|
|
A male patient has a long face, a large jaw, large ears, autism, and macroorchidism. What is the most likely diagnosis?
|
Fragile X syndrome (remember: Fragile X = eXtra large testes, jaw, ears)
|
|
|
What are the three steps of DNA polymerase chain reaction in order?
|
Denaturation, annealing, elongation
|
|
|
What word describes the phenomenon of a single gene having more than one effect on an individual's phenotype?
|
Pleiotropy
|
|
|
What neoplasms are associated with neurofibromatosis type 1?
|
Neural tumors, optic pathway gliomas, pheochromocytoma, and overall increased tumor susceptibility
|
|
|
A 4-year-old boy needs to use his upper extremities to push against his legs in order to stand up. What is the name of this maneuver?
|
Gower's maneuver; the action is necessary due to the weakness of the proximal muscles
|
|
|
What equation describes the disease prevalence in a population that is in Hardy-Weinberg equilibrium?
|
p2 + 2pq + q2 = 1; where q2 is the prevalence of an autosomal recessive disease
|
|
|
What property of Sanger DNA sequencing is crucial to the ability to determine a DNA sequence using electrophoresis?
|
A dideoxyribonucleotide must interrupt the sequence at every base in the sequence
|
|
|
True or False? The sensitivity and specificity of the enzyme-linked immunosorbent assay approaches 100%.
|
True; however, false-negative and false-positive results may still occur
|
|
|
A newborn has microcephaly and epicanthal folds and produces a high-pitched crying or mewing sound. What is the most likely diagnosis?
|
Cri-du-chat syndrome
|
|
|
What is the most common genetic mechanism leading to Down syndrome?
|
Meiotic nondisjunction
|
|
|
In cloning, what is the significance of inserting DNA to be replicated into plasmids also containing antibiotic-resistance genes and then growing the bacteria on media containing the antibiotic that bacteria is resistant to
|
This technique selects for replication of the plasmid containing genes for antibiotic resistance AND the DNA of interest
|
|
|
Fragile X syndrome is caused by a defect in which gene?
|
FMR1; the name of the gene stands for Familial Mental Retardation
|
|
|
How is DNA separated into two strands during polymerase chain reaction?
|
By heating
|
|
|
Treatment with what drug helps to loosen mucous plugs in patients with cystic fibrosis
|
N-acetylcysteine
|
|
|
In genetics, what does the term imprinting refer to?
|
When, at a single locus, one allele is inactivated by methylation (an inherited condition) and one allele is not (disease occurs as the result of the loss of the active allele)
|
|
|
What phase of mitosis are the chromosomes in when performing a karyotype?
|
Metaphase
|
|
|
Prader-Willi and Angelman syndromes are the result of which genetic process?
|
Genetic imprinting
|
|
|
A tall male patient enters the emergency room with the combination of a dissecting ascending aorta and acute mitral valve prolapse; what disorder might explain these findings?
|
Marfan's syndrome is associated with cystic medial necrosis of the aorta which may lead to a dissection, as well as a floppy mitral valve prone to prolapse
|
|
|
Compared to the general population, patients with tuberous sclerosis have an increased incidence of which brain tumor?
|
Astrocytoma
|
|
|
What is the role of restriction enzymes in DNA cloning?
|
Restriction enzymes cleave DNA at 4-6 base pair palindromic sequences, allowing for insertion of a fragment into a plasmid
|
|
|
What is the pattern of inheritance of hypophosphatemic rickets?
|
X-linked dominant
|
|
|
How is the size of a DNA fragment determined from an agarose gel?
|
A DNA ladder of known lengths is run alongside the polymerase chain reaction fragments
|
|
|
What is the mode of inheritance of tuberous sclerosis?
|
Autosomal dominant
|
|
|
How does an antibiotic-controlled promoter allow you to study genes in which the deletion of that particular gene leads to death of the embryo?
|
The gene can be manipulated at specific times during development
|
|
|
True or False? Oncogenes, in a manner similar to tumor-suppressor genes, must have a deletion/mutation in the complementary allele before cancer develops.
|
False; the mutation of a single oncogene can produce cancer
|
|
|
Adult polycystic kidney disease is inherited in an autosomal-_____ (dominant/recessive) pattern, whereas infantile polycystic kidney disease is associated with an autosomal-_____ (dominant/recessive) pattern.
|
Dominant; recessive
|
|
|
The vascular tumors of von Hippel-Lindau disease are commonly seen in which parts of the nervous system?
|
Retina, cerebellum, medulla
|
|
|
Marfan's syndrome is the result of a mutation in the _____ gene.
|
Fibrillin
|
|
|
True or False? Patients with autosomal-dominant disorders often present clinically after puberty.
|
True; in order for the diseases to remain in the population, affected people must have offspring
|
|
|
What allows fluorescence in situ hybridization analysis to detect deletions too small to visualize on karyotype?
|
The fluorescent probes used can bind small segments of DNA and illustrate the presence or absence of genetic material
|
|
|
Which would travel further on an agarose gel: a 10-kD or an 100-kD DNA fragment?
|
The 10-kD fragment; smaller molecules travel further
|
|
|
A 50-year-old patient develops depression, progressive dementia, and choreiform movements. What is the most likely diagnosis?
|
Huntington's disease; symptoms usually begin between 20 and 50 years of age
|
|
|
Which assay would allow you to detect single nucleotide polymorphisms?
|
Microarrays
|
|
|
What is the pattern of inheritance of cystic fibrosis?
|
Autosomal recessive
|
|
|
What is the advantage of a fluorescence in situ hybridization analysis over a karyotype
|
It allows researchers to identify anomalies at a molecular level, including deletions that are too small to see on a karyotype
|
