Histology Block 2 PQ
A 2-year-old child is taken to her physician because of yellowish discoloration of the sclera and the skin that has aggravated the past 2 months, fatigue, shortness of breath, dizziness and light headedness. Patient history revealed that her mother, aunt, and brother have a history of hereditary spherocytosis, a condition where erythrocytes are sphere-shaped rather than bi-concave disk shaped. What cellular structure normally maintains the bi-concave shape of erythrocytes? Iron binding Heme Subunit A. A, B, O Antigen Surface Glycoproteins B. Nuclear Transmembrane Proteins C. Cytoskeletal Proteins D. Globin Polypeptide Subunits
C. Cytoskeletal Proteins
In an experimental subject, the stratum corneum is progressively removed using adhesive tape. Which of the following is most likely to occur at the site of stripping? A. Increased accumulation of keratohylin granules B. Increased accumulation of keratin C. Increased water loss D. Decreased blood flow E. Decreased diffusion of lipids F. Decreased melanin production
C. Increased water loss SC, most apical, is stratified squamous keratinized (dead) epithelium cells responsible for water barrier.
A 27-year old female has experienced sudden onset and unexplained weight gain with fat deposits throughout her body, most notably in her face giving rise to a more rounded appearance. She also complains of abnormal thirst and urination, loss of libido and amenorrhea (absence of menstruation) and growth of extra facial hair. Radiologic examination revealed a mass in her pituitary gland, as well as adrenal gland hyperplasia (enlargement). Given the combination of symptoms experienced by the patient, which of the following pituitary cell types is most likely affected? Thyrotrophs Mammotrophs Gonadotrophs Pituicytes Corticotrophs
Corticotrophs
A 7-year old girl has an infection. A complete blood count reveals increased numbers of the white blood cell type shown in the image. Which of the following conditions is most consistent with this laboratory result? A. Parasitic Infection B. Viral Infection C. Allergic Reaction D. Bacterial Infection E. Chronic Inflammation
D. Bacterial Infection
The fovea centralis of the retina is important in ocular function because: A. It is the area of highest visual acuity B. It is the area where the optic nerve leaves the eye C. It represents the anterior limit of the visual retina D. It plays a role in the drainage of the aqueous humor E. It anchors the lens to the ciliary body
A. It is the area of highest visual acuity
A concerned mother brings in her 5 month old son for examination because she has redvently noticed lots of bruises on his legs and arms and cannot figure out where they are coming from. Blood work revealed low blood platelet count (thrombocytopenia) but normal levels of all other clothing factors. After months of examination her son is diagnosed with an autoimmune disorder that affects bone marrow cells. Which of the following bone marrow cells is most likely affected? A. Megakaryocytes B. Myeloblasts C. Promyelocytes D. Proerythroblasts E. Basophilic Erythrocytes
A. Megakaryocytes
Many conditions affecting WBC can be diagnosed by examining peripheral blood smear counts. During blood cell counts and differentials, WBCs are counted manually in specially designed chambers or with automated machines. The absolute number of each type of WBC can be calculated if the differential and the total number of leukocytes per volume unit are known. Which of the following blood cells is the most abundant type of leukocytes? A. Neutrophils B. Monocytes C. Eosinophils D. Erythrocytes E. Thrombocytes
A. Neutrophils
11. Which of the following findings would be associated with BPPV symptoms? A. Otoliths bending crista stereocilia during angular movements of the head B. Otoliths bending macula stereocilia during linear movements of the head C. Otoliths at the macula of the saccule D. Otoliths within the membranous sacs of the vestibule E. Otoliths bending macula stereocilia during tilting of the head
A. Otoliths bending crista stereocilia during angular movements of the head
A 32 year old female is diagnosed with a pituitary adenoma, a tumor arising from the secretory cells of the adenohypophysis. Given the location of the tumor, symptoms of such a condition vary widely depending on the type of cells and hormones involved. All of the following are possible symptoms resulting from overproduction of hormones within the adenohypophysis EXCEPT: A. Painful labor-like contractions of the uterus in females. B. Changes in menstrual cycles in women and erectile dysfunction in men. C. Weight loss, anxiety, elevated heart rate, and BP changes D. Acromegaly (enlargement of extremities or limbs and thinking of the skull and jaw)
A. Painful labor-like contractions of the uterus in females.
In which stage of development in the erythrocyte linage is the presence of hemoglobin first visible with the light microscope? A. Polychromatophilic erythroblast. B. Normoblast. C. Basophilic erythroblast. D. Reticulocyte. E. Eosinophilic Myelocyte.
A. Polychromatophilic erythroblast.
Which of the following histological observations would be abnormal and a sign of a possible clinical condition, select all that apply: A. Presence of melanocytes in stratum spinosum B. Presence of melanocytes in stratum Basale C. Absence of melanocytes in stratum spinosum D. Absence of melanocytes in stratum Basale E. Presence of pigmentation in keratinocytes in stratum Basale F. Absence of pigmentation in melanocytes in stratum Basale G. Absence of pigmentation in keratinocytes of the stratum Basale H. Absence of pigmentation in melanocytes of the stratum Basale
A. Presence of melanocytes in stratum spinosum D. Absence of melanocytes in stratum Basale F. Absence of pigmentation in melanocytes in stratum Basale G. Absence of pigmentation in keratinocytes of the stratum Basale
Which of the following structures within the eye contain pigment granules? A. RPE B. Cornea C. Sclera D. Choroid E. Ciliary Body F. Outer plexiform layer G. Iris H. Fovea I. Dilator Pupillae
A. RPE D. Choroid E. Ciliary Body G. Iris I. Dilator Pupillae Choroid, ciliary body, iris are all part of the middle pigmented and vascularized layer with CT. Think of them as 1 unit when thinking about what layer. Dilator Pupillae, a muscle, composed of myoepithelial (contractile) cells that are pigmented! Outer layer that is semi continuous with inner layer.
A 23 year old male is diagnosed with hyper hydrosis, a condition characterized by excessive sweating in hands. Excessive secretion by which of the following glands is most likely responsible for this patient's sweaty palm of hands and soles of feet? A. Sodium chloride rich sweat from eccrine glands B. Pheromone rich sweat from sebaceous glands C. Hypotonic water rich sweat from apocrine glands D. Oil rich sweat from eccrine glands E. Protein rich from sebaceous glands
A. Sodium chloride rich sweat from eccrine glands
In your infectious disease sub-internship, you see a patient who has been experiencing fevers and fatigue. His white cell count comes back and you see that his neutrophil levels are elevated. What type of diagnosis do you suspect? A. Viral infection B. Bacterial infection C. Cancer D. Allergic reaction E. Parasitic infection
B. Bacterial infection
A 45 year old male experiencing severe headaches visits his local hospital where radiological exams revealed a tumor in the pars Distalis of his pituitary gland, but no infiltration or impingement of the pars Nervosa. Given the location of the tumor, symptoms of such a condition vary widely depending on the types of cells involved. Secretion of following hormones could be affected, EXCEPT: A. Antidiuretic hormone B. Thyroid stimulating hormone C. Luteinizing hormone D. Growth hormone E. Adrenocotropic hormone
A. Antidiuretic hormone
A 35 year old man comes to the physician because of pain and swelling of his right arm where he scraped it on a tree branch 2 days ago. His temperature is 38.3ºC (101ºF). Examination of the right forearm shows welling around a fluctuant lesion at the site of trauma, and upon perforation of the skin a thick yellowish pus exudate can be observed likely due to a bacterial infection. Which of the following cell types is most likely elevated in his peripheral blood? A. Band Neutrophils B. Megakaryocytes C. Basophilic Metamyelocytes D. Normoblasts E. Myeloblasts
A. Band Neutrophils Options B-E do not leave the bone marrow ever. Their daughter cells leave. But band neutrophils (immature cell) can leave BM to mediate bacterial infections.
An 82 year old woman has degenerative retinal disease involving the foveal-macular area of the left eye. She is the most likely to have lesions of optic nerve fibers leading to loss of vision in which of the following visual fields? A. Central B. Inferonasal C. Inferotemporal D. Peripheral E. Supranasal
A. Central Fovea centralis with CONES -> loss of colored vision. She would have a hard time reading books and seeing other detailed objects
A 60 year old man with a history of smoking presents with chest pain and mild fever. The patient is subsequently diagnosed with lung cancer. Which of the following best describe the capillary in the alveoli of the lungs? A. Continuous endothelial cells with continuous basal lamina. B. Discontinuous endothelial cells with discontinuous basal lamina C. Endothelial cells with fewest rations covered by diaphragms D. Fenestarted endothelial cells with continuous basal lamina E. Sinusoid also capillary with discontinuous basal lamina
A. Continuous endothelial cells with continuous basal lamina.
A 67 year old man visits the outpatient clinic with complaints of deteriorating vision. A form of glaucoma is diagnosed in which the aqueous humor is not drained properly, likely due to narrowing of the Canal of Schlemm. Which region of the eye should you examine to analyze the integrity of this canal? A. Corneoscleral junction near the limbus region B. Ciliary processes near the lens equatorial region C. Sclera near the fovea centralis region D. Choroid near the blood vessels at the optic disc E. Corneal stroma near the anterior aqueous chamber
A. Corneoscleral junction near the limbus region
The lens is a transparent, biconvex structure in the eye that, along with the cornea, helps to refract light to be focused on the retina. Which of the following accurately describes the structural basis for the lens' transparency? A. Covered by stratified squamous epithelium B. Contains elongated anuclear cells filled with crystallins C. Has dense regular CT tissue capsule D. Highly organized Bowman's membrane E. Contains abundant BV
B. Contains elongated anuclear cells filled with crystallins
Organize the layers of the pericardium and heart in the correct order from outermost (facing body cavity) to innermost (facing heart chambers) A. Myocardium, visceral pericardium, fibrous pericardium, parietal pericardium B. Fibrous pericardium, parietal pericardium, visceral pericardium, myocardium C. Fibrous pericardium, visceral pericardium, parietal pericardium, myocardium D. Myocardium, parietal pericardium, visceral pericardium, fibrous pericardium E. Parietal pericardium, visceral pericardium, fibrous pericardium, myocardium
B. Fibrous pericardium, parietal pericardium, visceral pericardium, myocardium
A 5 year old boy is a seen by a dermatologist after experiencing a series of unexplained blisters and scars that often become infected. A diagnosis of bullous pemphigoid, a genetic skin condition that results from inadequate adhesion at the dermoepidermal junction was made after examination. Abnormalities in which of the following structures would most likely be associated with bullous pemphigoid A. Desmosomes of cells at the stratum Spinosum B. Hemidesmosomes of cells at the stratum Basale C. Keratin only in granules of cells at the stratum granulosum D. Lysosomes of Langerhan's cells at the stratum Spinosum E. Pigment granules of melanocytes in the stratum Basale
B. Hemidesmosomes of cells at the stratum Basale *Want hemidesmosomes to attach to BM to resists the pull. Stratum Basale is between epidermis and dermis so this is the layer that is affected, has hemidesmosomes. Hemidesmosomes attach intracellularly to keratin which is an intermediate filament.
Physiologists are studying the bio molecular mechanisms underlying cardiac muscle contraction. They have been analyzing muscle fibers obtained from knockout mice to determine how different cellular substances influence muscle contraction. Cardiomyocytes obtained from a specifically mouse embryo fail to contract following stimulation of cells at the opposite end of a chain. No abnormalities in cytoskeletal fibers are observed. A deficiency of which of the following would best explain this finding? A. Gap Junctions B. Desmosomes C. Adherens Junctions D. Tight Junctions E. Hemidesmosomes
A. Gap Junctions anytime two cells are communicating and they are not neurons - they are using GAP JNS
Which of the following accurately describe composition and structure of the Tunica Adventitia? A. Contains numerous elastic laminae for proper recoil during diastole. B. Houses vasa vasorum which supply nearby SMC. C. Contains the outermost layer of endothelium surrounding the entire vessel wall. D. Consists primary of SMC that secrete Type 1 collagen fibers. E. Becomes gradually thicker as arteries branch into smaller arterioles.
B. Houses vasa vasorum which supply nearby SMC. Tunica Adventitia blends with surrounding CT, hard to distinguish cut off. The SMC cells farthest from lumen need nutrients bc the ones closest to IEL and lumen take the nutrients first. Vaso vasorum = vessels of the vessels
Neuroendocrine signaling cascades that regulate cortisol secretion primarily involve coordinated activity amongst: A. Hypothalamus, parathyroid, adrenal B. Hypothalamus, pituitary, adrenal C. Liver, pituitary, adrenal D. Pituitary, adrenal, parathyroid
B. Hypothalamus, pituitary, adrenal
A friend of yours returns home following a summer vacation at the beach. You notice that her skin has become darker. Which of the following biological processes accounts for this change in skin coloration? A. Increased number of granular keratinocytes B. Increased production of melanin C. Increased thickness of the stratum corneum D. Migration of melanocytes into the stratum corneum
B. Increased production of melanin
Which of the following cell types secretes substances that prevent blood coagulation and increase the permeability of small BV to allow movement of cells from the blood into adjacent CT? A. Endothelial cells B. Mast cells C. Eosinophils D. Fibroblasts E. Thrombocytes F. Neutrophils
B. Mast cells
Pheochromocytomas are tumors that usually lead to hyper secretion of catecholamines. Which region of the adrenal gland is involved in production of catecholamines? A. Capsular CT B. Medulla C. Zona fasciculata D. Zona glomerulosa E. Zona reticularis
B. Medulla
Which part of the retina of the eye lacks photoreceptors? A. Suspensory ligaments B. Optic disc C. Ciliary body D. Macula dense E. Fovea centralis
B. Optic disc
Treatment with a cochlear implant (replacing the structures within the cochlear ducts) successfully restored near-normal hearing. Damage to which of the following structures would most likely explain the patient's symptoms? A. Crista Ampullaris hair cells B. Organ of Corti hair cells C. Cochlear nerve fibers in the modiolus D. Ossicles in the middle ear E. Macular of the utricle hair cells
B. Organ of Corti hair cells
Which of the following structures transforms vibration of teh ossicles into waves of fluid in the cochlea? A. Ampullae B. Oval window C. Round window D. Tympanic membrane E. Utricle
B. Oval window
Which of the following best describe the functions of the retinal pigment epithelium? Select all that apply. A. Synapse with photoreceptors during light detection B. Phagocytose membranous disks C. Modify retinol/retinal for recycling D. Contain choiroidal capillaries to supply rods and cones E. Absorb light via melanin granules F. Form Decemet's membrane G. Protect retinal via blood-retina barrier
B. Phagocytose membranous disks C. Modify retinol/retinal for recycling E. Absorb light via melanin granules G. Protect retinal via blood-retina barrier
A 62 year old man is brought to the office due to recurrent headaches and vomiting. Neurological examination suggests and intracranial mass located in the dorsal midbrain. These types of tumors typically arise from the pineal gland; it is therefore possible for this patient to experience circadian rhythm abnormalities. Which of the following best describes normal regulation of circadian rhythms? A. Darkness stimulates melanin production B. Sunlight inhibits pinealocyte secretion C. Darkness stimulates pituicyte secretion D. Sunlight stimulates melatonin production E. Darkness inhibits pinealocyte secretion
B. Sunlight inhibits pinealocyte secretion P is from pituitary gland and pinealocyte is from pineal gland. Melatonin comes from pineal gland! Take melatonin at night, melatonin is active at night.
Thick and thin skin may be distinguished in the following ways: A. Thin skin possesses a stratum granulosum but thick skin does not B. Thin skin possesses hair follicles but thick skin does not C. Thin skin is located on the palms and soles, thick skin is on the remainder of the body D. Thin skin possesses ridges and grooves but thick skin does not E. Thick skin has fewer sweat glands than thin skin
B. Thin skin possesses hair follicles but thick skin does not
A few minutes after allowing his girlfriend's pet rat (Bob) and mouse (Susie) to crawl on his arm, Mike develops raised, red, itchy skin. Which blood cell would have caused a reaction at this site?
Basophil, trying to mediate inflammatory reaction.
A group of medical residents are studying the organization and secretory mechanisms of adenocarcinmoas, cancerous tumors arising from exocrine gland cells. Which of the following statements accurately describe exocrine glands? A. Cells secrete compounds from their basal surface directly to blood vessels. B. Cells secrete proteins primarily via apocrine mechanism C. Cells secrete compounds into ducts that connect to an apical surface D. Consist of groups of specialized secretory CT cells E. Exist only as simple tubular arrangements of cells
C. Cells secrete compounds into ducts that connect to an apical surface
A 64 year old man comes to the ED due to loss of vision in the right eye that occurred suddenly several hours ago. Ophthalmoscopic examination reveals the patient's symptoms are due to detachment between the two retinal layers. The stuctures of the outer fibrous and middle vascular layers of the reye wall do not exhibit any abnormalities. Which of the following structures is derived from the retina and would most likely be affected in this patient? A. Iris connective tissue B. Anterior lens epithelium C. Ciliary epithelium D. Corneal epithelium E. Choroid blood vessels
C. Ciliary epithelium Retina is the inner layer of the wall of the eye, derived from neuroepithelium. Two separate epithelial layers that can detach. Anterior lens and corneal epithelium covers lens and are are derived from ectoderm, not neuroepithelium so not part of the retina. Choroid BV is another CT in the middle vascular layer.
A 20-year-old female visits her physician complaining of recurring but brief episodes of unexplained vertigo and intense dizziness usually when she turns over or sits up in bed. Lately even walking has been triggering these symptoms, causing her to lose her balance. Her physician performs a series of maneuvers to confirm his suspected diagnosis of benign paroxysmal positional vertigo (BPPV), a condition caused by otoliths becoming dislodged from their normal location. Which of the following findings would be associated with BPPV symptoms? Otoliths bending crista stereocilia during angular movements of the head Otoliths at the macula of the saccule Otoliths within the membranous sacs of the vestibule Otoliths bending macula stereocilia during tilting of the head Otoliths bending macula stereocilia during linear movements of the head
Otoliths bending crista stereocilia during angular movements of the head
A 32-year old woman visits her physician due to a month of nasal discharge, coughing and sore throat. She is diagnosed with a subtype of blood cancer resulting in uncontrolled production of abnormal agranulocytes. Erythrocyte and granulocyte counts are within normal limits and their bone marrow precursors appear normal as well. Which of the following is the most likely consequence of this patient's condition? Inadequate response against viral infections Inadequate vasodilation and blood coagulation Normal levels of blood monocytes Inadequate response against parasitic infections Decreased blood reticulocytes
Inadequate response against viral infections
A 47-year-old male is diagnosed with hyperparathyroidism due to parathyroid chief cell overstimulation and insensitivity to feedback regulation. As a result of his condition, this patient will most likely experience which of the following? Increased bone density Decreased osteoclast activity Decreased intestinal calcium reabsorption Increased blood calcium Decreased secretion of calcitonin
Increased blood calcium
A 53-year-old female is diagnosed with hyperparathyroidism due to parathyroid chief cell hyperplasia, with subsequent rise in blood levels of parathyroid hormone (PTH). Which of the following best describes the effects of increased PTH secretion on blood calcium and bone resorption? Increased blood calcium levels and increased osteoclast activity Decreased blood calcium levels and increased osteoclast activity Increased blood calcium levels and decreased osteoclast activity Decreased blood calcium levels and increased bone density Increased blood calcium levels and increased bone density
Increased blood calcium levels and increased osteoclast activity
A 3-year old child is brought to the clinic due to tonsilitis, swollen tonsils due to local infection and increased activation of lymphocytes present in the lamina propria of the oral epithelium near the tonsillar region. If a biopsy of the tonsils was obtained, which of the following would most likely be observed upon histopathological examination? Presence of hassl's corpuscles Enlarged regions of white pulp Increased numbers of primary nodules Increased numbers of secondary nodules Absence of germinal centers
Increased numbers of secondary nodules
A 3-year old child is brought to the ophthalmologist, her mother suspects she may need to wear glasses because she is constantly tripping over objects and has difficulty playing ball games. She is diagnosed with Stargardt disease, a rare form of inherited juvenile macular degeneration that involves the breakdown and loss of cones (photoreceptors) in the macular region of the neural retina. Which of the following symptoms would most likely be associated with loss of cones in the retina? Inability to see distant objects Loss of central vision Inability to perceive black and white light Loss of peripheral vision Inability to see during nighttime
Loss of central vision
A drug that blocks secretory activity of pituitary acidophilid cells would most likely: A. Decrease secretion of calcitonin from the thyroid gland B. Increase secretion of oxytocin from the posterior pituitary C. Decrease secretion of growth hormones by mammotrophs D. Decrease stimulation of mammary glands E. Increase secretion of aldosterone by adrenal gland
D. Decrease stimulation of mammary glands Acidophilic = pink so think PINK; boobs! - somatotrophs and mammotrophs (Growth Hormone and Prolactin). Oxytocin is not the same as prolactin, it is secreted from Pars Nervosa (other is ADH). Growth Hormone is secreted by somatotrophs. Prolactin is by mammotrophs. Aldosterone regulated by ACTH (secreted by basophilic)
Which of the following statements best describes the conduction system of the heart? A. The fibrous skeleton of the heart electrically insulates the LA from RA B. Innervation from the CNS to the SA Node is necessary for the heart to contract C. Every cardiomyocyte in the RV receives direct input form purkinje fibers and then sends impulses to cardiomyocytes of the RV through gap junctions D. Impulses from the SA node cannot directly activate contract of myofibers in the ventricles. The signals must first pass through the AV node.
D. Impulses from the SA node cannot directly activate contract of myofibers in the ventricles. The signals must first pass through the AV node.
A 30 year old woman diagnosed with Addison's disease, adrenal gland insufficiency most commonly caused by autoantibodies against the adrenal cortex, without affecting chromaffin cells. Examination of adrenal gland biopsy confirms the diagnosis by revealing atrophy of all 3 cortical zones. As a result of her condition, this patient will mostly exhibit which of the following symptoms? A. Insomnia and sleep abnormalities B. Abnormal cell metabolism, heat production, sweating C. Headaches, low HR, depression, anxiety D. Inadequate regulation of urine volume and BP E. Low blood calcium levels and brittle bones
D. Inadequate regulation of urine volume and BP A is from melatonin. B is from thyroid hormones. C is from chromaffin cells. E is from Calcitonin and PTH
A 32 year old woman visits her physician due to a month of nasal discharge, coughing and sore throat. She is diagnosed with a subtype of blood cancer resulting in uncontrolled production of abnormal Agranulocytes. Erythrocytes and granulocytes counts are within normal limits and their bone marrow precursors appear normal as well. Which of the following is the most likely consequence of this patient's condition? A. Normal levels of blood monocytes B. Inadequate response against parasitic infections C. Decreased blood reticulocytes D. Inadequate response against viral infections E. Inadequate vasodilation and blood coagulation
D. Inadequate response against viral infections Agranulocytes: monocytes, lymphocytes -> functions are more widespread b. Granulocytes: neutrophils, eosinophils, basophils -> more specific functions
A 29 year old woman has been treated for mild anemia since childhood but visits her family physician due to worsening episodes of breathlessness and fatigue. Concerned about this persistent anemia despite therapy, she is referred to the hematology department, where genetic tests revealed her anemic symptoms were due to a rare type of hemoglobin mutation. Which of the following laboratory findings is most likely to support this diagnosis? A. Increased blood oxygen levels B. Decreased blood carbon dioxide levels C. Decreased blood reticulocyte levels D. Increased blood reticulocyte levels E. Increased blood myelocyte levels
D. Increased blood reticulocyte levels Reticulocytes (immature erythrocytes) are released into the blood to compensate for blood loss.
Suspected of having a rare genetic disorder, a patient and her daughter both have biopsies of their thymus. The biopsy of the thymus of the daughter shows a highly cellular thymus that contains many lymphocytes, while the maternal thymus appears less robust, with large areas of adipose tissue and numerous inclusions. What can you conclude based upon the results of this test? A. The mother is showing signs of abnormal tissue damage. B. The daughter may be experiencing an autoimmune reaction. C. Nothing, the thymus is normally active in adults. D. Nothing, these are normal observations of pre and post puberty thymus samples. E. Nothing, the thymus is normally inactive until puberty.
D. Nothing, these are normal observations of pre and post puberty thymus samples.
A 62-year old woman comes to the hospital with intense chest pain that has gradually worsened over the last 36 hours. Family history reveals the patient likely suffers from Marfan syndrome, a genetic condition that results from abnormal elastic fiber assembly. On the fifth day of hospitalization she dies suddenly, despite adequate resuscitation. The autopsy report describes an intact aorta. Rupture of which of the following types of blood vessels is the most likely cause of death in this patient? Venules Capillaries Distributing Arteries Veins Arterioles
Distributing Arteries
Which of the following describes the function of a Langerhans cell in the epidermis? A. Anchoring cell to the basement membrane B. Protective cell against UV radiation C. Touch receptor cell between cells of the stratum Basale D. Cell that produces keratinohyalin granules for the stratum granulosum E. Antigen presenting cell in the epidermis
E. Antigen presenting cell in the epidermis
Auto immune disease that targets and destroys the cells indicated by the black arrow would most likely cause which of the following deficits? A. No vision from the central vision in affected eye B. Decreases sensitivity to color from both eyes C. Inadequate lens adaptation D. Decreased sensitivity to dim light during night time E. Blindness from both eyes
E. Blindness from both eyes
An 18 year old woman comes to the office due to a slowly enlarging, irregularly shaped mass on her left auricle. She had an ear piercing at this site 6 months ago but there were no immediate complications such as bleeding. It's likely that the mass was caused by keloids, formed after excessive growth and thickening of DCT. Which of the following skin layers would most likely exhibit abnormal thickening during keloids? A. Epidermis stratum corneum B. Dermis papillary layer C. Superficial cortex D. Hypodermis E. Dermis reticular layer
E. Dermis reticular layer - DCT A would be a callous, B is LCT.
A 3yo child is brought to the ophthalmologist because his father suspects he needs glasses. He is diagnosed with retinitis pigmentosa, a rare genetic disorder that involves the breakdown and loss of light sensitive rods (photoreceptors) in the neural retina. Which of the following symptoms would be most likely associated with loss of rods in the retina? A. Inability to perceive color B. Inability to see distant objects C. Loss of high visual acuity regions D. Loss of central vision E. Inadequate night time vision
E. Inadequate night time vision
A drug that specifically depletes monocytes would block formation of which of the following? A. B lymphocytes B. Helper T lymphocytes C. Natural killer cells D. Erythrocytes E. Macrophages
E. Macrophages
A 45 year old homeless man comes to the ED because of a 1 week history of pain in his right foot and a 2 day history of difficulty walking. His sock is blood encrusted. Physical examination shows a 5 cm wound surrounded by edema on the ball of the right foot. A thick exudate containing abundant dead and dying leukocytes is expressed on palpating of the wound. Which of the following types of leukocytes most likely predominated at the wound 1 day after the initial injury? A. Basophils B. B lymphocytes C. Eosinophils D. Monocytes E. Neutrophils F. T lymphocytes
E. Neutrophils
10. A 20 year old female visits her physician complaining of recurring but brief episodes of unexplained vertigo and intense dizziness, usually when she turns over or sits up in bed. Lately, even walking has been triggering these symptoms, causing her to lose balance. Her physician performs a series of maneuvers to confirm the suspected diagnosis of benign paroxysmal positional vertigo (BPPV), a condition caused by otoliths becoming dislodged from their normal location. Which of the following best describes the location of otoliths? A. Tectorial membrane of Organ of Corti B. Cupula of crista ampullaris C. Otolithic membrane of the cupua D. Macula of the crista ampullaris E. Otolithic membrane of the macula
E. Otolithic membrane of the macula
Patients diagnosed with CF ar at risk for DF in fat soluble vitamins (ADEK) due to intestinal malabsorption. CF patients can experience vision impairments since vitamin A DF impedes rhodopsin formation and results in abnormal rods within the retina. Histological examination of the neural retina in this condition would most likely reveal abnormal roads in which of the following layers? A. Inner plexiform layer B. Retinal pigment epithelial layer C. Nerve fiber layer D. Choroid fibrous layer E. Outer nuclear layer
E. Outer nuclear layer
Accommodation in the eye is mediated by contraction of the ciliary muscle as follows: A. The pupil constricts to focus the image on the fovea B. The lens moves forward to focus the image on the fovea C. Tension in the zonula is increased and the cornea thickens D. The cornea flattens to adjust its refractive index E. Tension in the zonule is decreased and the lens thickens
E. Tension in the zonule is decreased and the lens thickens
24 year old Joey was backpacking though the foothills of mount Tibidabo. After his return, he experienced ongoing GI upsets due toa parasitic infection. A blood smear was performed. Which blood cell would most likely be increased in this situation?
Eosonophil, whose function is to mediate parasitic infections.
A 46-year-old female was diagnosed with systemic lupus erythematosus. Autoimmune disorders like lupus may develop if lymphocytes do not undergo adequate immunocompetency education and rigorous selection processes. Which of the following cell types within the thymus mediate the positive and negative selection of developing T cells? Epithelioreticular Cells Dendritic Cells Thymic Macrophages Follicular Dendritic Cells Reticulocytes
Epithelioreticular Cells
A 79-year-old female visits her local otolaryngologist after her family complained that she speaks too loudly, and watches TV in extremely high volume. She has experienced difficulty detecting both high pitch and low pitch sounds. All of her symptoms seem to be gradually worsening over time. Her doctor knows that because of her age she is likely experiencing age-related hearing loss (presbycusis), but she's concerned it may be due to neural degeneration. Which of the following findings would be indicative of neural presbycusis? Thickening of the organ of Corti Increased endolymph volume and distended membranous labyrinth Stiffening of the basilar membrane Loss of spiral ganglia within the modiolus Prominent cochlear nerve within the modiolus
Loss of spiral ganglia within the modiolus
A 3-year-old girl from Tanzania was referred to the Hospital with severe anemia, fever, cough, pallor, weakness and tachypnea that aggravated six day ago. On abdominal examination, she had hepatosplenomegaly, and blood work revealed sickle-cells. Splenomegaly is often observed in children with sickle-cell anemia since damaged red blood cells are filtered at the spleen and removed by: Follicular Dendritic Cells Monocytes Macrophages Epithelioreticular Cells Lymphocytes
Macrophages
A 56 year old comes to the office due to difficulty hearing from both ears but is otherwise healthy and hasn't experienced any episodes of dizziness or vertigo. For the past 12 years, he has worked in a factory where he has to shout to communicate with coworkers and has seldom worn hearing protection. If it was determined that this patient's hearing loss was caused by Meniere's Syndrome, a condition where excess EL buildup causes increased pressure and dissension of the membranous labyrinth, which of the following structures would also be at risk of being damaged? A. Vestibule periosteum B. Saccule perilymph C. Scala vestibule D. Crista ampullaris E. Modiolus spiral ganglia
D. Crista ampullaris
A concerned mother brings in her 5-month-old son for examination because she has recently noticed lots of bruises on his legs and arms and cannot figure out where they are coming from. Blood work revealed low blood platelet count (thrombocytopenia) but normal levels of all other clotting factors. After months of examination her son is diagnosed with an autoimmune disorder that affects the bone marrow cells. Which of the following bone marrow cells is most likely affected? Proerythroblasts Promyelocytes Megakaryocytes Myeloblasts Basophilic Erythrocytes
Megakaryocytes
A 42-year-old woman comes to the physician for a routine examination. She is concerned about a mole on her arm that suddenly started to grow in size, and is changing colours and texture. You suspect she may be showing symptoms of melanoma, a type of skin cancer that develops from melanocytes usually after prolonged period of ultraviolet light exposure. Which of the following best describes cancerous melanocytes? Melanocytes that have migrated into the stratum spinosum Melanocytes that do not appear pigmented Melanocytes that have had the tips of their cytoplasmic processes phagocytosed by keratinocytes Melanocytes that have migrated into the stratum basale Melanocytes that actively produce melanosomes
Melanocytes that have migrated into the stratum spinosum
A 37-year old female experiencing severe migraines visits her local hospital where radiological exams revealed a mass in the pars distalis of her pituitary gland. Given the location of the mass, symptoms of such a condition vary widely depending on the type of cells involved. Secretion of all of the following cells could be affected, EXCEPT: Mammotrophs Oxytotrophs Thyrotrophs Somatotrophs Gonadotrophs
Oxytotrophs
A 32-year-old female is diagnosed with a pituitary adenoma, a tumor arising from the secretory cells of the adenohypophysis. Given the location of the tumor, symptoms of such a condition vary widely depending on the type of cells and hormones involved. All of the following are possible symptoms resulting from overproduction of hormones within the adenohypophysis, EXCEPT: Weight loss, anxiety, elevated heart rate and blood pressure changes Acromegaly (enlargement of the extremities or limbs and thickening of the skull and jaw) Painful labor-like contractions of the uterus in females Changes in menstrual cycles in women and erectile dysfunction in men Inappropriate growth of breasts and increased lactation
Painful labor-like contractions of the uterus in females
A 24-year-old male moved from Canada to Australia to attend medical school, and as expected he experienced feelings of jet-lag. One month after his flight he is still experiencing difficulty falling asleep at night time and fatigue throughout the daytime. After attending the endocrine lecture in his histology class, he self-diagnoses as having abnormal levels of melatonin. If his diagnosis is correct, this is most likely indicative of abnormal secretory activity of which of the following cell types? Pinealocytes Chief Cells Pituicytes Oxyphil Cells Melanocyte
Pinealocytes
Polycythemia is a disease state in which the hematocrit is elevated. Which hematopoietic cell would be most actively proliferating in this condition? Myeloblast Myelocyte Megakaryocyte Lymphoblast Proerythroblast
Proerythroblast
A group of medical students are studying the processes that give rise to near and distant vision. They feel overwhelmed by the complex histological structures involved in accommodating the lens to properly bend light rays so that they focus on the retina. They examine the appearance of these structures once the lens has fully accommodated for distant vision, which of the following histological findings would most likely be observed? Relaxed sphincter pupillae muscle Contracted ciliary muscle Decreased size of pupil Taut zonular fibres Round lens
Taut zonular fibres
Where are the otoliths of the inner ear normally located? the maculae of the saccule and utricle the tectorial membrane the Organ of Corti the perilymph of the vestibule the cupula of the cristae ampullaris
the maculae of the saccule and utricle
On your way home after a long day in your endocrinology rotation you read about a 29-year old male patient who has undergone unexplained muscle wasting, increased heat production, and bulging eyes. He complains of difficulty breathing and swallowing due to swelling/enlargement in his anterior neck region. After analyzing the histopathology results (image attached), you are able to confirm your diagnosis of an autoimmune condition called Grave's disease. Antibodies responsible for causing the patient's condition are directed against cells producing which of the following hormones? Parathyroid Hormone Aldosterone Thyroid Hormones (T3/T4) Calcitonin Growth Hormone
Thyroid Hormones (T3/T4)
A 2-year infant is being treated for fragile skin that blisters easily, especially on the hands and feet. Her mother states that she has also seen scalp blistering, scarring and hair loss. It is possible that this patient suffers from a condition in which keratinocyte desmosomes are mutated thus affecting the adhesion between adjacent cells of the epidermis. If true, which of the following would most likely be a primary concern for this patient's prognosis? Decreased density of resident Pacinian corpuscles Vulnerability to infections due to compromised barrier Loss of interstitial fluids due to detachment between epidermis and dermis Vulnerability to UV rays due to absence of skin pigmentation Inadequate levels of adipose for insulation and thermoregulation
Vulnerability to infections due to compromised barrier
A group of medical students studying the histological composition of the heart wall obtain and analyze a biopsy sample. They are able to locate 4 distinguishable structures (see attached image). Which of the following statements correctly matches the structures to their function? 3: Z-lines of sarcomeres anchoring thin filaments 4: Contractile cells located within the endocardium 1: Perinuclear region storing primarily lipids as an energy source 2: Non-contractile cells located within the myocardium 2: Non-contractile cells specialized for electrical conduction
2: Non-contractile cells specialized for electrical conduction
A 4 yo girl is found to hand non-syndromic deafness. The physician suspects that her condition is autosomal recessive. Mutations in the gene for connexin 26 account for 50% of these cases. In individuals with normal hearing, connexin 26 recycles K+ to the stria vascularis, where it can be secreted back into the endolymph. In healthy subjects, the endolymph has an increased K+ concentration compared with both typical intracellular and extracellular fluid. If this patient has a decreased K+ concentration in the endolymph, disruption of which of the following processes would best explain the deafness? A. AP repolarization in the vestibulocochlear nn that depends on the K+ concentration in the endolymph. B. Auditory hair cells which are metabolically supported by basal cells that require K+ to secrete trophic factors. C. Influx of K+ that depolarizers auditory hair cells in response to basilar membrane movement. D. Movement of the basilar membrane that depends upon a K+ ion gradient across its apical surface E. K+ ions that increase the osmilarity of the endolymph so that fluid is not lost from the cochlea
C. Influx of K+ that depolarizers auditory hair cells in response to basilar membrane movement. EL is high K+ -> hits basilar membrane -> depolarizes auditory hair cells -> hair cells/stereocilia bend -> channels on stereocilia (modified microvilli) open and K+ enters = start of electrical signals that move to the cochlear nn fibers
Administration of a drug that causes increased secretion of NE and Epi by the adrenal medulla. This most likely occurs because the drug: A. Increases ACTH secretion B. Inhibits steroid hormone production C. Mimics activity of sympathetic neurons D. Activates enzymes that mediate breakdown of cortisol derivatives E. Stimulates release of hypothalamic inhibitory hormones
C. Mimics activity of sympathetic neurons
A 54 year old man visits his physician due to episodic burning substernal chest pain. His pain increases with activity and improves with rest. A perfusion scan reveals a myocardial infarction (loss of oxygen supply to cardiac muscle) following occlusion of a large coronary artery. A bypass surgery is scheduled to restore blood flow to the affected areas. During surgery, in which of the folllowing layers of the heart wall are you most likely to locate the affected cardiac muscle? A. Epicardium B. Endocardium C. Myocardium D. Pericardium E. Mesothelium
C. Myocardium
He first tried using hearing aids, but this did not alleviate his symptoms. Hearing aids are used to treat conductive hearing loss, they amplify sound waves in order to compensate for stiffening of various structures of the inner ear. All of the following structure vibrates during auditory transduction and can cause conductive hearing loss when stiffened except: A. Tympanic membrane B. Oval window C. Otolithic membrane D. Basilar membrane E. Tectorial membrane
C. Otolithic membrane
A 10 month old infant is brought to the ophthalmologist, her mother suspects she may be experiencing problems with vision. Careful examination of the eye reveals an underdeveloped ciliary body with deficient epithelial cells lining the ciliary processess. Which process would be most affected if the ciliary processes fail to form? A. Contraction of sphincter pupillae B. Formation of optic nerve fibers C. Production of zonular fibers D. Depolarization of photoreceptor cells E. Differentiation of lens fibers
C. Production of zonular fibers Functions of ciliary processes - 1) produce zonular fibers (suspensory ligaments) that extend from epithelial cells toward edge of lens = lens accommodation AND 2) secrete aqueous humor -> posterior chamber -> pupil -> anterior chamber -> supplies cornea and lens
9. The cochlear duct, utricle, saccule and semicircular ducts make up the membranous labyrinth. It is known as the "membranous" because it is composed of a series of epithelially lined continuous spaces. The epithelium was derived from which of the following embryological sources? A. Neural tube ectoderm B. 1st pharyngeal arch mesoderm C. Surface ectoderm D. Endodermal epithelium E. 2nd pharyngeal cleft mesoderm
C. Surface ectoderm
Glaucoma is a group of eye diseases which result in damage to the optic nerve and vision loss. The most common cause for glaucoma is degeneration of the drainage system of aqueous humor leading to increased resistance and thus a chronic, painless buildup of intra-ocular pressure. Which of the following structures is most likely involved in the pathogenesis of this type of glaucoma? Ora Serrata Vitreous Chamber Optic Disk Choroid Plexus Canal of Schlemm
Canal of Schlemm
A 56-year old patient is brought to the emergency department due progressive shortness of breath and chest tightness. Histopathological examination of a tissue biopsy reveals degeneration of the cells pictured in the attached image and replacement by scar tissue (resembles dense irregular connective tissue). Based on this patient's biopsy findings, disruption to which of the following processes is most likely causing his symptoms? Gas exchange across the endothelial lining of the heart chambers Contraction of smooth muscle in the tunica media of blood vessels Secretion of serous fluid by pericardial cells Signal transduction through Purkinje fibers in the epicardium Contraction of cardiomyocytes in the myocardium
Contraction of cardiomyocytes in the myocardium
The aqueous humor fills the anterior and posterior chambers of the eye. It is one of the fundamental components in ensuring that the optical physics and health of your eye are properly maintained. Any changes in the composition of aqueous humor may be detrimental to structures within the eye whose nourishment is derived from this fluid. Which of the following structures would be most affected by decreased nutrient content within the aqueous humor? Ciliary Body Retinal Pigment Epithelium Neural Retina Cornea Iris
Cornea
Which of the following best describes the structures in order from most anterior to posterior through which light passes as it enters the eye? Sclera - aqueous chamber - pupil - lens - vitrous chamber - RPE - neural retina - choroid Cornea - vitrous chamber - pupil - lens - aqueous chamber - neural retina - RPE - choroid Cornea - aqueous chamber - pupil - lens - vitrous chamber - RPE - choroid - neural retina Cornea - aqueous chamber - pupil - lens - vitrous chamber - neural retina - RPE - choroid Sclera - vitrous chamber - pupil - lens - aqueous chamber - RPE - neural retina - choroid
Cornea - aqueous chamber - pupil - lens - vitrous chamber - neural retina - RPE - choroid
During a post-mortem examination of the layers of the eye wall you notice that with the exception of the neural retina they are primarily composed of either connective tissue or epithelial tissue. Which of the following epithelially-derived structures is composed of a stratified layer of epithelial cells? Corneal endothelium Corneal epithelium Ciliary epithelium Retinal pigment epithelium Anterior lens epithelium
Corneal epithelium
A group of medical students are studying the processes that give rise to near and distant vision. They feel overwhelmed by the complex histological structures involved in accommodating the lens to properly bend light rays so that they can focus on the retina. They examine the appearance of these structures once the lens has fully accommodated for near vision, which of the following histological findings would most likely be observed? A. Relaxed ciliary muscle B. Flattened lens C. Contracted sphincter pupillae muscle D. Relaxed zonula fibers E. Increased size of pupil
D. Relaxed zonula fibers Contraction of ciliary muscle -> less or more tension on zonula fibers -> controls lens accommodation FAR = taut zonula fibers = wide & flat lens NEAR = relaxed zonula fibers = round lens Pupil and iris involved in light adaptation, not near or far accommodation
Marfan's syndrome results from abnormalities in fibrillin and its association with tropoelastin. Which of the following blood vessel tunics would be most affected with this condition: A. Tunica adventitia of arterioles B. Tunica media of veins C. Tunica intima of distributing arteries D. Tunica media of elastic arteries E. Tunica intima of venules
D. Tunica media of elastic arteries
The mother of a 14 month old boy complains that her son has a fever, cough, and nasal discharge. Physical examination reveals an upper respiratory tract infection and a bulding tympanic membrane. The boy is subsequently diagnosed with otitis media secondary to an upper RTI. The infection and inflammation in this patient affect which of the following areas of the ear? A. Vestibular labyrinth B. Organ of Corti C. External acoustic meatus D. Tympanic cavity E. Cochlear labyrinth
D. Tympanic cavity
A 5-year old child is brought to the ophthalmologist, his mother suspects he may need to wear glasses because he is constantly tripping over objects and has difficulty playing ball games. The source of the visual deficit is found to be due to an underlying malformation of the photoreceptor cells of the retina. Which of the following regions should you examine to best analyze the integrity of such cells? Fovea centralis Helicotrema Limbus region Ora serrata Ciliary processes
Fovea centralis
A 76-year-old male visits his local otolaryngologist after his family complained that he speaks too loudly, and watches TV in extremely high volume. He has also experienced difficulty understanding speech and detecting all high pitch sounds overall but hasn't noticed any changes in hearing low pitch sounds. All of his symptoms seem to be gradually worsening over time. His doctor knows that because of his age he is likely experiencing noise induced hearing loss (presbycusis). The patient's symptoms are most consistent with damage of which of the following structures? Oval window Endolymphatic duct Hair cells near the base of the basilar membrane Hair cells near the apex of the basilar membrane Tectorial membrane along the entire organ of Corti
Hair cells near the base of the basilar membrane
A 34-year old woman comes to the office with chronic hypertension and irregularities in urine production. She also experienced abnormal menstrual periods and hirsutism (male-pattern hair growth). Laboratory studies reveal elevated blood levels of both androgens and aldosterone, but normal cortisol levels. Which of the following histopathologic findings are most likely to be present in this patient's adrenal glands? Atrophy (cell death) of the zona glomerulosa and fasciculata Hyperplasia (enlargement) of the zona fasciculata and reticularis Hyperplasia (enlargement) of the adrenal medulla Hyperplasia (enlargement) of the zona glomerulosa and reticularis Atrophy (cell death) of all layers of the adrenal cortex
Hyperplasia (enlargement) of the zona glomerulosa and reticularis
A 14-year old teenage boy is being treated for recurrent infections caused by an underlying condition called agammaglobulinemia, an inherited immune deficiency characterized by a low concentration of antibodies in the blood due to the lack of B lymphocytes. Which region in lymph nodes would most likely be poorly developed in this patient? Deep cortex Red pulp Superficial cortex PALS Medullary cords
Superficial cortex
A 67-year old man visits the clinic with a 15-year history of coughing, fatigue, and headaches. Patient history reveal he worked for over 30 years as a construction worker in demolition sites known to contain asbestos. As a result of his chronic exposure to air filled with this foreign substance, the resident macrophages of the lungs, dust cells, would have phagocytosed the asbestos for years requiring constant turnover and replacement. Given this patient's medical history, which of the following cell types would most likely be elevated in a peripheral blood smear? Monocytes Eosinophils Neutrophils Lymphocytes Thrombocytes
Monocytes
Which of the following statements best describes the cell labeled by the black arrows in the image below? Granules released are toxic to parasites and worms Does not undergo transendothelial migration Most abundant leukocyte Is classified as an agranulocyte Largest leukocyte Phagocytoses viral infected cells
Most abundant leukocyte
A 32-year old male is presumed to suffer from a subtype of leukemia, a condition in which hematopoietic stem cells undergo abnormally high rates of proliferation releasing early progenitor cells into peripheral blood. Presence of which of the following cell types in a peripheral blood smear would best support your diagnosis? Band neutrophil Neutrophilic myelocyte Erythrocyte Reticulocyte Megakaryocyte fragments
Neutrophilic myelocyte
2 year old Emma was playing at Central Park and got a sliver in her foot. Two days later the area containing the sliver was red with a white exudate. If a smear was taken of this material, what would the predominant cell type be?
Neutrophils. Pus is evident of phagytosed bacteria.
During hormone regulation, hormones are released, either directly by an endocrine gland or indirectly through the action of the hypothalamus of the brain, which stimulates other endocrine glands to release hormones in order to maintain homeostasis. Which of the following hormones is NOT secreted nor regulated by the hypothalamus? Oxytocin from neurohypophysial axons Norepinephrine from chromaffin cells T3/T4 hormone from follicular epithelial cells Luteinizing hormone from gonadotrophs Mineralocorticoids from zona glomerulosa
Norepinephrine from chromaffin cells
A 37-year old man is admitted to the emergency department with ear pain, tinnitus (ringing in her ears), dizziness and vertigo. Radiographic examination reveals indications of excessive build-up of perilymph fluid within the inner ear. Which of the following structures is filled with perilymph and therefore would be the most vulnerable to injury in this patient's condition? Utricle Scala media Scala tympani Semicircular duct Modiolus
Scala tympani
Histopathological examination of the structures of the inner ear reveals atrophy of hair cells in one ampullary region near the inner ear vestibule, which of the following sensory processes is most likely affected? Hearing low frequency sounds Hearing high frequency sounds Sensing "up-down" axis linear acceleration of head Sensing "yes-no" axis angular acceleration of head Sensing tilting and position of head
Sensing "yes-no" axis angular acceleration of head
A 7-month-old baby is brought to an audiologist after his parents noticed their baby didn't recognize their voice and was not turning his eyes or heads towards sudden and loud sounds. A series of tests were performed to test the cause of the child's symptoms, and the audiologist was able to diagnose conductive hearing loss caused by a disturbance in the transmission of sound to the inner ear. The baby's symptoms were completely reversed when he was given a set of hearing aids that amplified the sound waves. Which of the following is the most likely cause of this child's conductive hearing loss? Atrophy of the stria vascularis Disjointed (discontinuous) ossicles in the middle ear Extensive loss of sensory hair cells along the basilar membrane Stiffening of the tympanic membrane Degeneration of the cochlear nerve
Stiffening of the tympanic membrane
A 32-year old woman comes to the office due to vision problems and frequent headaches. Brain MRI reveals a large anterior pituitary tumor compressing on the optic chiasm. Light microscopy examination of the tumor reveals hormone-secreting basophils. Which of the following processes is regulated by pituitary basophils and is most likely affected in this patient? Circadian rhythm and sleeping patterns Stimulation of gonads including ovarian follicles Growth of bones, muscle and adipose Bone resorption by osteoclasts Contraction of uterine muscle during labor
Stimulation of gonads including ovarian follicles
A biopsy of cancerous skin is performed to obtain a sample of the affected cells, known to be abnormally proliferating stem cells arising from the epidermis. Which layer would you examine to locate stem cells within the skin? Stratum granulosum Stratum spinosum Stratum corneum Stratum basale Stratum reticularis
Stratum basale
A group of scientists are investigating genetic variations underlying clinical cases of ectodermal gland damage. A knock-out mouse is engineered with deficient eccrine sweat glands, which of the following processes would be most likely affected in this animal model? Moisturizing of skin via sebum secretion Rate of cell proliferation in hair follicles Density of Meissner's corpuscles in papillary regions Thermoregulation via sweat evaporation Pheromone-mediated interactions
Thermoregulation via sweat evaporation
You receive a sample for histopathological study but it's missing its label. You study in your light microscope and notice that it consists of stratified squamous keratinized epithelium resting on a thick layer of dense irregular connective tissue (DICT). Embedded within the DICT you notice a series of light staining glands adjacent to hair follicles, but you can't seem to locate any sensory receptors. In order to find the right label, you look through the pending requests and the following tissues are waiting to be examined. Which of the following labels matches the histological features of your sample? Thin skin lacking sebaceous glands Thin skin with sebaceous glands Thick skin with many Meissner's corpuscles Thick skin with eccrine glands Thin skin with many Pacinian corpuscles
Thin skin with sebaceous glands
This image shows the eye of a 48-year old man. Investigation showed that excess insoluble proteins resulting in increased opacity of the lens. This condition is called cataracts, and often results from reduced solubility of which of the following lens components? crystallins basement membrane type I collagen type V collagen zonular fibers
crystallins