习题与答案五

《组织学与胚胎学》习题与答案五是非题11.Covering epithelia cover the external and internal surfaces of the body, including the linings of vessels and other small cavities.2.Epithelium usually has a free surface and a basal surface, both of which possess the same structure but different function.3.The core of the microvilli contains fine actin filaments, which interconnected with the terminal web.4.The core of a microvillus is composed of nine outer doublet microtubules and two ce ntral singlet microtubules.5.Between opposing cell membrane, where the gap junction occurs, numerous connexo ns span. Ions and sm all molecules can pass freely between opposed epithelia l cells via the gap junction.6.Between the epithelium and the underlining connective tissue is the basem ent me mbrane.7.The basement membrane provides for a strong connection, increases the basal surface area and serves as a semi-permeable membrane.8.Blood vessels and nerves never pass through the basement membrane and penetrate into epithelial tissues.9.Plasma membrane infoldings promote transportation of water and ions without e nergy consume.10.Specializations of the basal surface of epithelium are basement membrane, desm osome, hemidesmosome, and plasma membrane infolding.11.Epithelial tissues line most body cavities and tracts and also specialize to form glan ds.Glands are mainly composed of glandular epithelia.12. The secretions of exocrine gland are discharged through a duct system and the sec retions of endocrine glands are directly released into the bloodstream.13. The cells in connective tissue usually have polarity.14. The only significant function of connective tissue is to provide structura l support for other tissues.15. Adipose tissue is also termed the areolar tissue.16. Hyaluronic acid is the principal constituent of ground substance in soft connective tissues.17. The fine structure of the fibroblast is typical of a cell involved in secreting steroid hormones.18. Mesenchyme is the embryological precursor of all connective tissues, including soft and skeletal tissuses.19. Mast cells exhibit the property of metachrom asia when stained with certain bluebasic dyes.20. Elastic fibers are also called yellow fibers because they are yellow in fresh sta te. 56. Lipid is contained in a large m embrane bound vesicle in adipocytes.21. Reticular tissue is mainly composed of fibroblasts and reticular fibers.22.Cartilage and bone tissues belong to connective tissue proper.23.Three types of cartilage can be distinguished by reference to the differences in q uantity and type of cells.24.Chondrocytes in fibrocartilage are completely enclosed by cartilage matrix and occup y small laculae.25.The inner layer of perichodrium is rich in osteoprogenitor cells, which are responsible for appositional growth of cartilage.26.Osteoblasts secrete fibers and organic ground substance and embed themselves into the bone matrix, thus the osteoid tissue is formed.27.Osteocytes and their processes are suspended in tissue fluid within lacunae and c analiculi, thus the nutrients and metabolites can be exchanged between the blood and the osteocytes.28.Osteoclasts secrete lysosomal enzymes, which break down the collagen and organic ground substance, thus the bone matrix is absorbed.29.The structural form of bone matrix is bone lamellae, which are present in the comp act bone but not in the spongy bone.30.In the bone tissue, the collagenous and elastic fibers are embedded in the amorpho us ground substance, and characteristically arranged in lamellae.31. Osteons consist of Haversian lamellae and a central Volkmann’s canal in which blood vessels and nerves pass through.32.Blood is a specialized form of connective tissue proper, consisting of blood cells and plasma.33.For examining the morphology of blood cells, blood sm ear is usually used and stain ed with Wright or Giemsa stain.34.The special shape of erythrocytes facilitates gaseous exchange.35.The biconcave shape of red blood cells is maintained by microtubules and microfila ments.36.The young erythrocytes in the bloodstream often containing ribosomes are termed reticulocytes.37.According to having granules in their cytoplasm or not, leukocytes are classified into two groups: granulocytes and agranulocytes.38.The cytoplasm of basophils has specific granules containing heparin and histaminase.39.Monocytes are capable of crossing capillary walls, and differentiate into lymphocyt es.40.All cells in blood are end cells, which no longer divide.41. Erythrocytes functions within blood vessels, while leukocytes function mainly outside the vessels.42.The skeletal muscle fibers branch and make gap junctions with neighbors.43.Perimysium is made up of connective tissue separating single muscle fibe rs.44.The cross striations form as a result of the dark and light bands of all myofibrils ina skeletal muscle fiber coinciding positionally at any particular level.45.The thin filaments of steletal muscle are anchored in the Z lines.46.The smooth muscle fibers have no cross striations under the LM, but have cross stri ations when observed under the EM.47.The cardiac muscle fibers contain a number of mitochondria indicating the great ene rgy consumption.48.The cardiac muscle fibers in the atrium are also a kind of endocrine cells.49.The sarcoplasmic reticulum of cardiac muscle is not well developed, so its contractio n is not dependent on extracellular Ca2+.50. According to the sliding filament hypothesis, contraction of the sarcom ere result from thin filaments sliding pass the thick filaments towards the M line.51.The central and peripheral processes of a pseudounipolar neuron are both axons str ucturally.52.Neurofibrils collect together to form nerve fibers.53.The longer the axon, the bigger the cell body of the parent neuron.54.Microtubules and microfilaments are present in the perikarya, but do not extend int o the axon and axon hillock.55.The dendritic spines are the sites to form synaptic contacts and receive information.56.Synaptic transmission involves that neurotransmitters are released into synaptic cle ft and then bind to the receptors on the postsynaptic membrane producing action pote ntial.57.In general, the shorter the internodes, the more the nodes of Ranvier and therefore, the greater the conduction velocity.58.Neuroglial cells can only be found in the gray matter but not in the white matter of the CNS.59.Nuclei of the neurons are not seen in the preparation of nerves because they are pr esent in the CNS and ganglia of the PNS.60. The nervous tissue does not contain connective tissue, and the connective tissue in the brain is brought in by the blood vessels.Answers1. T2. F3. T4. F5. T6. T7. F8. F9. F 10. F 11. T 12. T 13. F 14. F 15. F 16. T 17. F 18. T 19. T 20. T 21. F 22. F 23. F 24. F 25. T 26. T 27. T 28. T 29. T 30. F 31. F 32. F 33. F 34. T 35. T 36. F 37. T 38. F 39. F 40. F 41. F 42. T 43. F 44. F 45. T 46. T 47. F 48. T 49. T 50. F 51. T 52. T 53. F 54. T 55. F 56. T 57. T 58. F 59. F 60. T 61. T是非题21.Inflammation of the cornea causes severe pain because corneal epithelium is rich in naked nerve endings.2.The iris divides the anterior compartment of the eye into anterior and posterior cham bers.3.The inner surface of the ciliary body is covered by a simple cuboidal epithelium, which plays a role in vision regulation.4.In the central fovea, all the layers of the retina are absent except the cone cells.5. In the retina, there are five main types of cells: pigm ent epithelial cells, photorecept or cells, bipolar cells, ganglion cells and Muller’s cells.31. Skin is the largest organ of the body, consisting of epidermis, dermis and hypodermis.6.Skin can be divided into the thick and thin types based on its thickness.7.Epidermis consists of two types of cells. They are non-keratinized cells and keratinized cells.8.The cells of the basal layer of epidermis contain a lot of ribosomes, tonofibrils and ke ratohyalin granules.9.Skin of the black contains many more m elanocytes than skin of the white.36.Melanocytes contain fewer melanin granules than epidermal epithelial cells in the deep layer.10. The sympathetic nerves m ediate the contraction of arrector pili muscles.11.Islets of Langerhans are most numerous in the head region of the pancreas.12.A cells and B cells are readily distinguishable from one another in EM or histoch emically stained preparations.13.Pancreatic exocrine tissue contains acini that secrete enzymes and o ther acini that s ecrete mucus.14.The HCO3- in pancreatic juice is secreted by the lining cells of the minute ducts rai ning the exocrine acini.15.The liver cells around the central vein obtain blood supply last and are damaged by som e harmful substances first.16.There are m any microvilli on the surfaces of the hepatocytes facing to the perisinus oidal space and bile canaliculi.17.The lumen of each bile canaliculus is called the space of Disse.18.Plasma m embrane of hepatocytes is the wall of the bile canaliculi.19.Although some hepatocytes exhibit polyploidy, most have the usual haploid numbe r of chromosomes.20. Both fat-storing cells and Kupffer cells can be seen in the hepatic sinusoids.21.The endothelial cells of blood vessels in the body are always flattened.22.Under the LM, capillaries can be divided into three types: continuous, fenestrated and sinusoidal capillaries.23.There are 40-70 layers of elastic membranes in the tuinca media of the large artery, so that it is called the elastic artery.24.The smooth muscle fibers of the arteries can produce ground substance, e lastic and collagenous fibers.25.The valves of the veins aid the flow of blood toward the heart and prevent flow in t he reverse direction.26.The Purkinje fibers are specialized neurons and conduct impulses much faster than ordinary cardiac muscle fibers.27.The coronary arteries are medium-sized type and represent the vasa vasorum of the heart.28.The wall of the aorta contains many layers of elastic membranes but no smooth mu scle cells.29.The arterioles of highly vascular tissues such as endocrine glands have a fenestrated endothelial lining.30. Major distributing arteries such as the femoral arteries are defined as muscular art eries.31.The antigen presenting cells are distributed in the lymphoid tissue and connective tissue but not in the epithelial tissue.32.The main difference between primary and secondary lymphoid nodules is the absence or presence of the germinal center.33.After stimulated by antigens T-lymphocytes divide and differentiate into plasma cells.34.The effector cells of both T and B cells actively take part in recirculation of lymphoc ytes.35.The paracortical zone of the lymph node is diffuse lymphoid tissue.36.The red pulp of the spleen is rich in blood cells because of high permeability of the splenic sinusoids.37.The parenchyma of the spleen can divided into the cortex and medulla.38.The high endothelial postcapillary venules are usually located in the diffuse lymphoid tissues.39.NK cells are a class of lymphocytes, which attack virus-infected cells and tumor cell s without previous antigen stimulation.40. The palatine tonsil is covered by stratified squamous epithelium, which is infiltrated with lymphocytes.41.The fine structure of the thyroid gland involves the synthesis and secretion of steroid hormones.42.The release of all hormones produec in the thyroid is controlled by thyroid stimulati ng hormone.43.The thyroid is unusual among the endocrine glands in that it stores large quantities of hormone precursors outside the cells.44.In an actively secreting thyroid gland, the follicles tend to be smaller in diameter, t he follicular cells become columnar and the colloid is decreased in volume.45.All the hormones secreted by the adrenal gland are steroid hormones.46.The zona reticularis secretes cortisol and sex hormones.47.Individual cells of the adrenal medulla secrete either noradrenaline or adrenaline but not both.48.The posterior pituitary is connected to the hypothalamus via a small mass of connec tive tissue known as the pituitary stalk.49.The target organs of oxytocin are ovary, uterus and mammary glands.50.Pituitary hormones that modulate the activity of other endocrine glands are known a s trophic hormones and are all secreted by the anterior lobe.51.In the anterior pituitary, the basophil cells are larger and more numerous than the acidophil cells.Answer1. T2. T3. F4. F5. T6. F7. F8. T9. F 10. F 11. T 12. T 13. F 14. T 15. F 16. T 17. T 18. T 19. F 20. T 21. F 22. F 23. F 24. F 25. T 26. T 27. T 28. F 29. T 30. F 31. F 32. T 33. F 34 F 35. T 36. F 37. F 38. T 39. T 40. T 41. F 42. F 43. T 44. T 45. F 46. T 47. T 48. F 49. F 50. T 51. F是非题31.The term mucosa or mucous membrane is used generally to describe a lining epitheli um, which secretes mucus.2.The minor glands in the wall of the digestive tract are always located in the lamina p ropria.3.The main function of the esophageal epithelium is protection.4.The main function of the stomach surface epithelium is to secrete mucus forming mu cus-HCO3- barrier.5.There is no skeletal muscle in the muscularis externa of the digestive tract.6.Peristalsis in a tubular viscera is dependent on the presence of at least two distinc t layers of smooth muscle disposed at right angles to one another.7.At the esophageo-gastric junction there is a gradual transition from esophageal to ga stric mucosa.8.The muscular wall of the small intestine consists of an inner circular and outer longit udinal layer of smooth muscle.9.Nerve plexus can be found between the two layers of smooth muscle of the muscular is in the digestive tract to control the contraction of the muscularis mucosae and exterrge intestinal mucus is principally involved in lubricating the passage of food re sidue and feces; it may also act as an important antibacterial mechanism.10.Ileum and colon are rich in the lamina propria in lymphoid tissues that frequently e xtend into the submucosa.11. Because the appendix is closed-ended, its contents are not renewed rapidly and it frequently becom es inflammated.12.Respiratory epithelium is an alternative term for pseudostratified columna r ciliated e pithelium.13.The nasal vestibules are lined by respiratory epithelium.14.In the trachea, a continuous layer of smooth muscle separates the lamina propria fr om the submucosa.15.In the tracheal wall, the disposition of cartilage in C-shaped rings permits the trach ea to expand in diameter and to increase in length during inspiration.15.The basement membrane underlying the tracheal epithelium is so thick that it is eas ily resolved in light microscopy.17.Submucosal serous and mucous glands are rarely found in primary bronchi.18.The smooth muscle of the bronchioles and terminal bronchioles is disposed in a com pletely circular layer.19.The term Clara cells is applied to the goblet cells in the epithelium of the terminal bronchioles.20.Pulmonary capillaries are of fenestrated type which enhances gaseous exchange with the alveoli.21.The alveolar lining cells contain numerous cytoplasmic pores known as alveolar pore s which facilitate gaseous exchange with the pulmonary capillaries.22.Erythrocyte production in bone marrow is stimulated by the hormone erythropoietin, secreted by the juxtaglomerular apparatus.23.The kidney is involved in maintenance of blood pressure by the production of angiot ensinogen, a powerful vasoconstrictor agent.24.The lumen of the renal tubule is co ntinuous with Bowman’s space.25.Most of the glomerular filtrate is absorbed in the distal convoluted tubule.26.The function of the Henle’s l oop is to generate an osmotic pressure in the renal inte rstitium such that water may be reabsorbed from the collecting tubules.27.The finding of a large number of mitochondria in the cells of the proximal convoluted tubule suggests that much active absorption takes place in this site.28.Collecting tubules, Henle’s loops and vasa recta make up t he bulk of the renal med ulla.29.The reabsorption of sodium ions from the distal convoluted tubule is coupled to the secretion of potassium and hydrogen ions.30.The cells of the macula densa are sensitive to the concentration of potassium ion s in the proximal convoluted tubule.31.The male urethra is lined by transitional epithelium.32.The testis is an organ that produces male germ cells and secretes m ale sex hormon es.33.Each testis is encapsulated by a dense connective tissue layer called tunica vaginalis.34.The seminiferous tubules are lined with a stratified epithelium that consists of sperm atogenic cells and Sertoli or supporting cells.35.Seminiferous tubules drain into the rete testis from which spermatozoa pass to the epididymis via the efferent ductules.36.Spermatogenesis is a process, in which spermatogonia successively divide and event ually differentiate into spermatids.37.Spermiogenesis is a complex process in which spherical spermatids divide and beco me into tadpole-like spermatozoa.38.The acrosome only covers the anterior two-thirds of the nucleus of spermatozoa.39.The human spermatozoon has a pear-shaped nucleus with its diploid chromosom es.40.The second meiosis of male gam etes completes just before fertilization.41. It takes about 64 days for spermatogonia to develop into spermatozoa in humans42. The number of follicles in the ovaries is gradually increased from the newborn infan t to the adult.43. Before ovulation the oocyte completes the 2nd meiosis and becomes a mature ovu m.44. Ovaries produce the ovum and female reproductive hormones.45. Ovaries consist of cortex and m edulla, both of which contain follicles.46. Before puberty, the cortex of the ovaries contains various stages of follicles and cor pus luteum.47. The primordial follicles are numerous and consist of an oogonium encapsulated bya single layer of squamous follicular cells.48. Primary follicles would normally be present in the ovaries of a five year old girl.49. In the secondary follicle, the granulosa cells surrounding the oocyte are arranged radially to form the corona radiata.50. The movement of ova along the oviducts is partially mediated by peristaltic action of the oviduct wall.51. The endom etrial glands chiefly consist of secretory ce lls and a few ciliated cells.52. The simple columnar ciliated epithelium of the oviduct a lso contains secretory cells.53. The predominant tissues in the non-pregnant, non-lactating breast are fibrous and adipose connective tissues.是非题1Answer1. F2. F3. T4. T5. F6. T7. F8. T9. F 10. T 11. T 12. T 13. T 14. F 15. F 16. T 17. T 18. F 19. T 20. F 21. F 22. F 23. T 24. F 25. T 26. F 27. T 28.T 29. T 30. T 31. F 32. F 33. T 34. F 35. T 36. T 37. F 38. F 39. T 40. F 41. T 42. F 43. F 44. T 45. F 46. F 47. F 48. F 49. T 50. T 51. T 52. T 53. T。