Histology NBME Review Flashcards
The intercellular passage of ions from the luminal surface of the intestines to the lamina propria is prevented by the presence of …
Desmosomes Belt desmosomes Hemidesmosomes Gap junctions Tight Junctions/Zonulae Occludens
Tight Junctions
Emphysema is characterized by overdistention & destruction of which of the following structures?
Trachea Bronchi Bronchioles Terminal bronchioles Alveolar ducts
Aveolar ducts- duct that carries into alveoli
A diurnally secreted biogenic amine synthesized in pinealocytes is?
Dopamine Epinephrine norepinephrine Melatonin serotonin
Pinealocytes are in pineal glad -MELATONIN- induce sleepiness
In the renal cortex, the labyrinth of capillaries that carry resorbed glucose out of the kidney arises directly from? Afferent arterioles Arcuate arteries Capsular plexus Efferent arterioles Intralobular arteries
EFFERENT ARTERIOLES directly connects to capillaries
The proliferation of uterine endometrium depends on? Cortisol Estrogen Luteinizing hormone Progesterone Prolactin
Proliferation is the follicular phase which secretes ESTROGEN luteal phase is progesterone
Which of the following cell types are found exclusively in the basal compartment of seminiferous tubules? Primary spermatocytes Secondary spermatocytes Spermatids Spermatogonia Spermatozoa
SPERMATOGONIA are exclusively found in basal. The rest are found in luminal compartment
A suitable marker for determining that cells have differentiated into epidermal epithelial tissue is expression of? Desmin Keratin Vimentin Histone H variant
Epithelial tissue to do with intermediate filaments. KERATIN or cytokeratin
A patient ingests an overdose of barbiturates. Which of the following will show greatest increase in hepatocytes 2 days later? Centrioles Glycogen Golgi cisternae Lysosomes Smooth endoplasmic reticulum
Processing of drugs happens in the liver by SMOOTH ENDOPLASMIC RETICULUM
During the final stage of secretory glycoprotein formation, before exocytosis, glycoproteins are found in the? Cisternae of rough endoplasmic reticulum Cis golgic complex Trans golgi complex Lysosomes Polysomes in the cystosol TR
TRANS GOLGI COMPLEX
Nucleus-> RER -> Golgi complex -> plasma membrane
Modifications occur at the golgi complex. Cis phase, medial phase, trans phase (L-R as proteins go throguh golgi)
The synthesis of rRNA is associated most specifically with which of the following cell structures? Kinetochores Nucleus envelope Nucleolus Ribosomes Rough endoplasmic reticulum
NUCLEOLUS - Where ribosomal subunits initially are
They may give a drawn picture and ask to identify the are. Nucleoulus is the dense region in the center of the nucleus
Beating of cilia is mediated by? Dynein arms Microfilaments Nexin links Reversible assembly-disassembly of microtubules Triplet microtubule units
DYENIN ARMS- associated with microtubules
Cilia associated with epithelial cells in trachea (9+2 dyenin arms)
A 26-yr. old woman with irregular menstrual cycles undergoes diagnostic endometrial biopsy. Histologic examination of the specimen shows long straight endometrial glands with narrow lumens that are embedded in a thick stratum functionale of the endometrium. These changes are most considered with which of the following findings?
Decreasing serum estrogen concentration stimulation release if luteinizing hormone releasing hormone from the hypothalamus
Diminishes activity of granulosa lutein cells in the ovary
Increasing secretion of pituitary FSH correlated with decreasing secretion of pituitary luteinizing hormone
Presence of a primary oocyte still encoded within the cumulus oophorous undergoing maturation prior to ovulation
Rapidly increasing viscosity and pH of vaginal secretions
DIMINISHES ACTIVITY OF GRANULOSA LUTEIN CELLS IN THE OVARY
Associated with proliferative phase. Estrogen is increasing because of proliferation of granulosa cells along with FSH
The blood brain barrier excluded which of the following molecules from the brain parenchyma? Albumin Choline Estrogen glucose tyrosine
ALBUMIN- cannot pass because of size
A substance of low molecular weight is injected into a cell. A short time later, the substance can be identified in the injected cell and in an adjacent cell. There is also evidence that the two cells are electrically coupled. EM is most likely to disclose which of the following structural specializations between these 2 cells? Chemical synapses Desmosomes (maculae adherents) Gap junctions Tight junctions (zonulae occludentes)
GAP JUNCTIONS- or connexons-> connexin protein (transmembrane protein)
Fenestrated capillaries are found in which of the following sites? Central nervous system lung Muscle Thymus Thyroid gland
THYROID GLANDS
Blood barrier in CNS (blood brain), lung, muscle, thymus (blood thymic barrier)
Which of the following differentiates capillaries in the brain from those in the gut?
Absence of a basement membrane
Absence of endothelial cell membrane fenestrations
Absence of a saturable transport mechanism for glucose
Presence of multiple endothelial cell nuclei
Presence of valves in the lumen
ABSENCE OF ENDOTHELIAL CELL MEMBRANE FENESTRATIONS
Blood brain barrier in the brain so close contact with epithelial cells with continuous basal membrane
In contrast to extrafusal muscle fibers, infrafusal fibers contain? A bands Motor nerve endings Sarcolemma Satellite cells Stretch-sensitive nerve endings
STRETCH-SENSITIVE NERVE ENDINGS
Muscle spindles- sensory receptors associated with skeletal muscle fibers which detect tension
The diagram represents the cytosolic surface of a normal erythrocyte PM Various proteins associated with the membrane are lettered A-E. A point mutation in which labeled protein results in spherocytosis
The rope shaped item is spectrin- A LETTER
Spectrin gives normal architecture to red blood cells - cytoskeletal protein
Cells will accumulate in which of the following phases of the cell cycle if they are cultivated in the presence of a chemical agent that is capable of blocking the cell cycle immediately after DNA synthesis has been completed? Metaphase of mitosis Anaphase of mitosis G1 S G2
G2 PHASE- is immediately after DNA synthesis
A tumor stained with a panel of monoclonal antibodies directed against various classes of intermediate filaments. The tumor stained positively with antiglial fibrillary acidic protein (anti-GFAP), indicating its derivation from? Astrocytes Endothelial cells of the brain Microglial precursors Oligodendrocytes Stromal fibroblasts of brain meninges
Anti-GFAP is an intermediate filament associated with ASTROCYTE
They may flip the question and ask what is the IF associated with astrocyte
To demonstrate graft versus host rejection to her students, an immunologist grafts the skin of a black male mouse onto an albino female mouse. The graft is rejected. Which of the following cell types present in the skin adjacent to the graft migrate into the graft to initiate an immunological response? Keratinocytes Langerhans’ cells Lymphocytes Melanocytes Merkel cells
LYMPHOCYTES are the T CELLS responsible for graft rejection
The dense spherical granules in this micrograph of a mammalian heart are likely sites for storage of?AcetylcholineAtrial natriuretic peptideCa2+ ATPaseGalactosyltransferaseGlobular actin
Refer to picture with lobule shaped with lots of dots- cardia cell
ATRIAL NATRIURETIC PEPTIDE- decreases blood pressure
The diagram is of the olfactory epithelium. The structures label X are?absorptive cellsGoblet cellsMitral cellsOlfactory receptors cellsSupporting cells
OLFACTORY RECEPTOR CELLS- the one with an X
Has pseudostratified epithelial cells- columnar cells, basal cells, olfactory epithelium
For the oocyte, meiosis is completed at the time of which of the following events? Extrusion of the first polar body Midcyle peak serum luteinizing hormone Peak serum follicle-stimulating hormone Peak serum inhibin Sperm entry into the secondary oocyte
SPERM ENTRY INTO THE SECONDARY OOCYTE- during this process there is completely of second meiotic division
Meiosis is complete in oocyte. Completion happens during fertilization.
Drugs, including alcohol, increase the number of detoxifying enzymes in the liver by extensive proliferation of which of the following cellular components? Golgi complex Lysosomes Mitochondria Rough endoplasmic reticulum smooth endoplasmic reticulum
SMOOTH ENDOPLASMIC RETICULUM
Which lettered structure on the diagram of muscle is most active during generation of energy necessary for contractions?
Skeletal muscle fiber- referring to mitochondria
LETTER C= MITOCHONDRIA
The most abundant type of cell within the fovea of the retina centralis? Bipolar Cone Ganglion Horizontal Rod
CONE- most abundant
In the eye
The cell type most responsible for recognition and rejection of foreign tissue in organ transplants? B lymphocyte T lymphocyte Macrophage Natural killer cell Neutrophil
T LYMPHOCYTES
Axons are characterized by the absence of which of the following organelles? Intermediate filaments Microtubules Mitochondria Rough endoplasmic reticulum Vesicles
ROUGH ENDOPLASMIC RETICULUM
An a 11yr old girl has severed her ulnar nerve. Which of the following cell types is important in promoting axonal regrowth? Epinerulial cells Fibroblasts Oligodendrocytes Perineurial cells Schwann cells
SCHWANN CELLS- process of nerve regeneration- promoting axonal growth
A recessive genetic mutation, white belly spot and tall (bst) is associated in mice with a failure of neural crest cells to migrate into the area of the umbilicus & the distal tail. The skin in these regions on infected mice lacks a population of cells that are devoid of desmosomes & keratin fibrils. Which of the following cell populations is most likely to be affected? Keratinocytes Langerhans’ cells Lymphocytes Melanocytes Merkel’s cell
MELANOCYTES- white belly spot because of failure of migration
A core of helical F-actin filaments provides the skeletal framework for? Ciliary axonemes Desmosomes Microvilli Nuclear laminae Nucleosomes
MICROVILLI- actin filaments are associated with these
The chart represents the changing amounts of RNA and hemoglobin in the erythroblast during erythrocyte formation. Which point best characterizes the condition found in the basophilic erythroblast? Point W Point X Point Y Point Z
POINT W
The vibrations of a tuning fork are most likely detected by? Bare nerve endings Golgi tendon organs Merkel’s cell receptors Muscle spindles Pacinian corpuscles
PACINIAN CORPUSCLES
Taste buds on the anterior 2/3 of the tongue are innervated by processes of cells in which the following ganglia? Geniculate Otic Pterygopalatine Submandibular Trigeminal
GENICULATE
The arrows in the photomicrograph indicate structures that are directly regulated by secretions? Chief cells of the parathyroid Chromaffin cells of the adrenal medulla Follicular cells of the Thyroid Glomerulosa cells of the adrenal cortex Pituicytes of the Neurohypophysis
CHEIF CELLS OF THE PARATHYROID- secretes parathyroid hormones
Photo will be in color- bone matrix is long gray region with circle center
Cells of which of the following hypothalamic nuclei secrete oxytocin into circulation? Mammillary Supreachiasmatic Supraoptic Tuberal Ventromedial
SUPRAOPTIC- secreted from hypothalmus (paraventricular (oxytocin) and supraotic (antiduaratic hormones mostly and small amounts of oxytocin)- secreted into pars nervosa
Which of the following cell types is most characteristic of terminal bronchioles? Basal Brush Ciliated Clara Mucous (goblet)
CLARA CELLS
Terminal bronchioles are simple layer of epithelial- not pseudostratified so no respiratory epithelium- mucous cells are only in bronchi
Brioncioles have clara cells or club cells
A 12yr old girl with chronic asthma is coughing up large amounts of mucus. Which of the following respiratory structure are the most likely source of mucus? Alveolar ducts Alveolar sacs Respiratory bronchioles Terminal bronchioles Tertiary bronchi
TERTIARY BRONCHI- goblet cells are found in the bronchi- excess mucous are secreted
Which of the following staining methods will clearly show abundant secretions of mucus in the bronchial epithelium? Hematoxylin and eosin Osmium tetroxide Periodic acid- Schiff (PAS) Sudan black Wrights stain
PERIODIC ACID-SCHIFF (PAS)
Which labeled structure in the photomicrograph of respiratory tissue shows the most proximal regions where respiration occurs?
E REGION- refers to proximal region of respiratory zone- alveolar duct, alveolar s, and alveoli- can identify individual alveoli