Histology Q&A

[Anonymous]

Q: What are the 3 layers of peripheral nerves? (inner to outer)
A: 1) Endoneurium
A: 2) Perineurium
A: 3) Epineurium

Q: Where is type I collagen found?(7)
A: 1. bone
A: 2. tendon
A: 3. skin
A: 4.dentin
A: 5.fascia
A: 6.cornea
A: 7.late wound repair

Q: Where is type II collagen found? (3)
A: 1. cartilage (including hyaline)
A: 2. vitreous body
A: 3.nucleus pulposus.

Q: What are the functions of the major structures of the inner ear bony labyrinth?
A: 1. Cochlea- hearing
A: 2.vestibule- linear acceleration
A: 3. semicircular canals- angular acceleration.

Q: What are the major structures of the inner ear bony labyrinth?
A: 1. Cochlea
A: 2. vestibule
A: 3. semicircular canals

Q: What are the major structures of the inner ear membranous labyrinth?
A: 1. Cochlear duct
A: 2. utricle.
A: 3. saccule
A: 4. semicircular canals.

Q: Name two proteins involved in the structure of macula adherens.
A: 1. Desmoplakin
A: 2.Keratin

Q: Name 6 functions of Golgi apparatus.
A: 1. Distribution center of proteins and lipids from ER to plasma membrane, lysosomes, secretory vessicles
A: 2. Modifies N-oligosaccharides on asparagine
A: 3. Adds O-oligosaccharides to Ser and Thr residues

Q: Next 3 functions of golgi
A: 4. Proteoglycan assembly from proteoglycan core proteins
A: 5. Sulfation of sugars in proteoglycans and of selected tyrosine on proteins
A: 6. Addition of mannose-6-phosphate to specific lysosomal proteins, which targets the protein to the lysosome

Q: Name two proteins involved in the structure of zona adherens?
A: 1. E-cadherins
A: 2. actin filaments

Q: Which cells are rich in smooth ER?
A: 1. liver hepatocytes, 2. steroid hormone-producing cells of adrenal cortex.

Q: Describe the immune response stimulated via Peyer's patches.
A: 1. M cells take up antigen.
A: 2. stimulated B cells leave Peyer's patch and travel through lymph and blood to lamina propria of intestine.

Q: Peyer's patches cont.
A: 3. In lamina propria B cells differentiate into IgA-secreting plasma cells.
A: 4. IgA receives protective secretory component.
A: 5. IgA is transported across epithelium to gut to deal with intraluminal Ag.

Q: Which cells are rich in rough ER?
A: 1. Mucus-secreting goblet cells of small intestine, 2. antibody-secreting plasma cells.

Q: What are the functions of the lymph node?
A: 1. Nonspecific filtration by macrophages.
A: 2. storage/proliferation of B and T cells
A: 3. Ab production.

Q: Where is type III collagen found? (5)
A: 1. skin
A: 2.blood vessels
A: 3.uterus
A: 4.fetal tissue
A: 5.granulation tissue

Q: Name five types of epithelial cell junctions.
A: 1. zona occludens
A: 2.zona adherens
A: 3.macula adherens
A: 4.gap junction
A: 5.hemidesmosome

Q: Describe microtubule arrangement of cilia.
A: 9+2 arrangement of microtubules.

Q: Describe the outer structure of a Peyer's patch.
A: A Peyer's patch is 'covered' by single layer of cuboidal enterocytes, interspersed with specialized M cells (no goblet cells).

Q: What is a lymph node? Include information on structural components.
A: A secondary lymphoid organ.
A: Has many afferents, one or more efferents.
A: With trabeculae.
A: Major histological regions = Follicle, Medulla, Paracortex

Q: What is the primary regulatory control of zona fasciculata secretion?
A: ACTH, hypothalamic CRH

Q: What is the primary regulatory control of zona reticularis secretion?
A: ACTH, hypothalamic CRH

Q: What are/is the primary secretory product of the zona glomerulosa?
A: aldosterone

Q: What do Brunner's glands secrete?
A: alkaline mucus

Q: What is the function of liver sinusoids?
A: Allow macromolecules of plasma full access to surface of liver cells through space of Disse.

Q: What is the function of a gap junction?
A: Allows adjacent cells to communicate for electric and metabolic functions.

Q: What is produced by alpha cells of the Islets of Langerhans?
A: alpha cells produce glucagon

Q: What three cell types are found in Islets of Langerhans?
A: alpha, beta, and gamma cells

Q: What type of cells are Nissl bodies found? In what parts of the cell?
A: Are found in neurons.
A: Are not found in axon or axon hillock.

Q: IN what area of the spleen are B cells found?
A: B cells are found within the white pulp of the spleen.

Q: What is type IV collagen found? (1)
A: basement membrane or basal lamina

Q: What is produced by beta cells of the Islets of Langerhans?
A: beta cells produce insulin

Q: What is the only GI submucosal gland?
A: Brunner's glands

Q: Describe the histological layers of the adrenal glands (outside to in)
A: Capsule, Zona glomerulosa, Zona fasciculata, Zona reticularis, Medulla.

Q: What are/is the primary secretory product of the adrenal medulla?
A: Catecholamines (Epi, NE)

Q: Memo to you.
A: Check out the picture in the book.

Q: Memo to you.
A: Check out the picture in the book. p. 105

Q: What do the medullary cords consist of?
A: Closely packed lymphocytes and plasma cells.

Q: What is the most common type of collagen?
A: Collagen Type I - 90%

Q: What is the most abundant protein in the human body?
A: Collagen.

Q: Define Islets of Langerhans.
A: Collections of endocrine cells.

Q: What is the function of hemidesmosomes?
A: Connect cells to underlying extracellular matrix.

Q: What are/is the primary secretory product of the zona fasciculata?
A: cortisol, sex hormones.

Q: What is another name for macula adherens?
A: Desmosome

Q: What is the effect of duodenal ulcers on Brunner's gland histology?
A: Duodenal ulcers cause hypertrophy of Brunner's glands.

Q: How does dynein function in cilia function?
A: Dynein causes the bending of cilium by differential sliding of doublets.

Q: What kind of protein is dynein?
A: Dynein is an ATPase.

Q: Describe the role of dynein in cilia structure.
A: Dynein links peripheral 9 doublets of microtubules.

Q: What makes endolymph?
A: Endolymph is made by the stria vascularis.

Q: What is Endoneurium?
A: Endoneurium invests single nerve fiber of the peripheral nerve.

Q: What is Epineurium?
A: Epineurium (dense connective tissue) surrounds entire never (fascicles and blood vessels)

Q: What is type X collagen found? (1)
A: epiphyseal plate

Q: Plasma is filtered on the basis of what properties?
A: Filtration of plasma occurs according to net charge and size.

Q: How is the glomerular basement membrane formed?
A: From the fusion of endothelial and podocyte basement membranes.

Q: What is produced by gamma cells of the Islets of Langerhans?
A: gamma cells produce somatostatin.

Q: What is the mnemonic to remember layers and products of adrenal cortex?
A: GFR (Glomerulosa, Fasciculata, Reticularis) corresponds to Salt (Na+), Sugar (glucocorticoids) and Sex (androgens)
A: The deeper you go, the sweeter it gets.

Q: What is the function of hair cells?
A: Hair cells are the sensory elements in both the cochlear and vestibular apparatus.

Q: Name a protein involved in the structure of hemidesmosomes.
A: Integrin.

Q: What is another name for zona adherens?
A: Intermediate junction.

Q: Describe the histological structure of sinusoids of the liver.
A: Irregular 'capillaries' with round pores 100-200 nm in diameter and no basement membrane.

Q: What is the function of smooth ER?
A: Is the site of steroid synthesis and detoxification of drugs and poisons

Q: What is the function of rough ER?
A: Is the site of synthesis of secretory (exported proteins and of N-linked oligosaccharide addition to many proteins.

Q: What part of pancreas are the Islets of Langerhans concentrated?
A: Islets of Langerhans are most numerous in the tail of pancreas.

Q: What structural defect causes Kartagener's syndrome? What is the consequence?
A: Kartagener's syndrome is due to dynein arm defect.
A: Results in immotile cilia.

Q: Define Pacinian corpuscles.
A: Large, encapsulated sensory receptors found in deeper layers of skin at ligaments, joint capsules, serous membranes, mesenteries.

Q: Where are Brunner's glands located?
A: Located in submucosa of duodenum

Q: Describe the histologic structure of sinusoids of the spleen.
A: Long, vascular channels in red pulp. With fenestrated 'barrel hoop' basement membrane.

Q: What is the histologic change in lymph nodes during an extreme cellular immune response?
A: Lymph node paracortex becomes enlarged during extreme cellular immune response.

Q: What is the histologic presentation of DiGeorge's syndrome?
A: Lymph node paracortex is not well developed in patients with DiGeorge's syndrome.

Q: What kind of cells are found nearby the sinusoids of the spleen?
A: Macrophages

Q: What are the major structures of the lymph node medulla?
A: Medulla consists of medullary cords and medullary sinuses.

Q: What do medullary sinuses communicate with?
A: Medullary sinuses communicate with efferent lymphatics.

Q: What do medullary sinuses consist of?
A: Medullary sinuses contain reticular cells and macrophages.

Q: What is the function of Meissner's corpuscles?
A: Meissner's corpuscles are involved in light discriminatory touch of glabrous skin.

Q: What is the histologic change in nephrotic syndrome? What is the consequence of this change?
A: Negative charge is lost.
A: Plasma protein is lost in urine

Q: What is the glomerular basement membrane coated with? (provides negative charge to filter).
A: Negatively charged heparan sulfate.

Q: What is the most common tumor the adrenal medulla in children?
A: Neuroblastoma

Q: What is the function of Pacinian corpuscles?
A: Pacinian corpuscles are involved in pressure, coarse touch, vibration, and tension.

Q: What do the Islets of Langerhans arise from?
A: Pancreatic buds.

Q: What specialized vascular structure is found in the lymph node paracortex? What is the function of this structure?
A: Paracortex contains high endothelial venules (HEV).
A: T and B cells enter from the blood through the HEV.

Q: What cells are found in the lymph node paracortex?
A: Paracortex houses T cells.

Q: What is Perineurium?
A: Perineurium (permeability barrier) surrounds a fascicle of nerve fibers.

Q: What is the most common tumor the adrenal medulla in adults?
A: Pheochromocytoma

Q: Compare the consequences of pheochromocytoma vs. neuroblastoma on blood pressure
A: Pheochromocytoma causes episodic hypertension
A: Neuroblastoma does NOT cause episodic hypertension

Q: What is the space of Disse?
A: Pores in liver sinusoids allowing plasma macromolecules access to liver cell surfaces.

Q: What is the primary regulatory control of adrenal medulla secretion?
A: Preganglionic sympathetic fibers

Q: What is the function of zona occludens?
A: Prevents diffusion across intracellular space.

Q: Describe the appearance and status of primary vs. secondary follicles.
A: Primary follicles are dense and dormant.
A: Secondary follicles have pale central germinal centers and are active.

Q: Describe the location of the lymph node paracortex.
A: Region of cortex between follicles and medulla.

Q: What is the primary regulatory control of zona glomerulosa secretion?
A: Renin-angiotensin

Q: What is the glomerular basement membrane responsible for?
A: Responsible for the actual filtration of plasma.

Q: What is another name for type III collagen?
A: reticulin

Q: What are Nissl bodies?
A: rough ER

Q: Where in the inner ear are the ampullae found? What is the function of this structure?
A: Semicircular canals contain ampullae
A: Functions in detecting angular acceleration.

Q: What are/is the primary secretory product of the zona reticularis?
A: sex hormones (e.g. androgens)

Q: What is the function of lymph node follicles?
A: Site of B-cell localization and proliferation.

Q: Define macula adherens.
A: Small, discrete sites of attachment of epithelial cells.

Q: Define Meissner's corpuscles.
A: Small, encapsulated sensory receptors found in dermis of palm, soles and digits of skin.

Q: What is an M cell? What is it's function.
A: Specialized cell interspersed between the cuboidal enterocytes covering a Peyer's patch.
A: M cells take up antigens.

Q: Name the layers of epidermis from surface to base.
A: stratum Corneum, stratum Lucidum, stratum Granulosum, stratum Spinosum, stratum Basalis.

Q: What is the location of zona adherens?
A: Surrounds the perimeter just below zona occludens.

Q: What is the function of Nissl bodies?
A: Synthesize enzymes (e.g. ChAT) and peptide neurotransmitters.

Q: In what area of the spleen are T cells found?
A: T cells are found in the PALS and the red pulp of the spleen.

Q: Which part of the cochlea picks up high frequency sound? Which picks up low frequency?
A: The base of the cochlea picks up high frequency sound
A: the apex picks up low frequency sound

Q: What is the bony labyrinth filled with? Describe its composition.
A: The bony labyrinth is filled with perilymph.
A: Perilymph is Na+ rich, similar to ECF

Q: What is the cause of I cell disease? What is the consequence?
A: The failure of addition of mannose-6-phosphate to lysosome proteins.
A: These enzymes are secreted outside the cell instead of being targeted to the lysosome.

Q: What is the membranous labyrinth filled with? Describe its composition.
A: The membranous labyrinth is filled with endolymph.
A: Endolymph is K+ rich, similar to ICF.

Q: What layer of the peripheral nerve must be rejoined in microsurgery for limb reattachment?
A: The perineurium must be rejoined in microsurgery for limb reattachment.

Q: Where in the inner ear are the maculae found? What is the function of this structure?
A: The utricle and saccule contain maculae
A: Functions in detecting linear acceleration.

Q: How is the function of gap junctions accomplished?
A: Through a connection with central channels.

Q: What is another name for zona occludens?
A: Tight junction.

Q: What are mnemonics for remembering locations for type I, II and IV collagen?
A: Type ONE: bONE
A: Type TWO: carTWOlage
A: Type FOUR: under the FLOOR (basement membrane)

Q: What is a Peyer's patch?
A: Unencapsulated lymphoid tissue found in lamina propria and submucosa of small intestine.

Q: What type of infection may induce an extreme cellular immune response? What happens to the lymph node during such an immune response?
A: Viral response is an example.
A: The paracortex enlarges.