TCDHA Histology- Lectures 1,2,3,4,5 Exam Questions With Verified Answers

cell - Answer smallest unit of life function: carry out vital processes of absorption, assimilation, respiration, irritability, conductivity, growth, reproduction and excretion exo/endocytosis - Answer exocytosis: expulsion of materials out of cell EX= EXIT endocytosis: uptake of materials into cell EN=ENTER -pinocytosis: cell drinking (pino=wine=drinking) -phagocytosis: cell eating cell membrane - Answer plasma membrane surrounds celll composed of phospholipid bilayer and proteins cytoplasm - Answer cytosol clear liquid enclosed in cell by cell membrane includes organelles and vacuoles organelles - Answer metabolically active specialized structures within the cell allow each cell to function according to its genetic code major organelles - Answer Nucleus Mitochondria Ribosomes Endoplasmic reticulum Golgi Apparatus Lysosomes Cytoskeleton tight junctions & location - Answer closes intercellular space between cells by fusing cell membranes together prevents movement/ loss of fluid location: lining of small intestine desmosomes & location - Answer bind cells together by creating spot welds between adjacent membranes location: cells of outer skin and oral mucosa Hemidesmosomes - Answer attachment of cell to adjacent non cellular surface allows gingival tissue to adhere to tooth surface by epithelial attachement gap junctions & location - Answer form tubular channels between cells- allow exchange of substances location:- muscle cells of heart -digestive tube life cycle of cell - Answer 1) interphase- DNA replication 2) mitosis- cell division 3) cytokinesis- cytoplasmic division 4) differentiation- less specialized becomes more specialized epithelial tissue - Answer forms protective coverings function in secretion/ sensory/ absorption protects inner structures from: -physical, chemical and pathogenic attacks -dehydration -heat loss (acts as barrier) connective tissue - Answer provides support for softer body parts binds structures together muscular tissue - Answer responsible for producing body movements nerve tissue - Answer conduct impulses- help control/coordinate body activites embryological cell layers - Answer ectoderm- skin/oral mucosa mesoderm- respiratory/digestive tracts endoderm- urinary tract epithelial cells are - Answer highly regenerative packed closely together tightly joined by desmosomes joined to basement membrane by hemidesmosomes epithelium - Answer avascular- no blood supply of its own nutrition is obtained by diffusion from connective tissue connective tissue- highly vascularized simple squamous epithelium - Answer thin, flat cells, vary in shape in 1 layer- nucleus bulges put covers connective tissue with little intercellular matrix- attached by basement membrane filtering function pn moist surfaces simple squamous epithelium- location - Answer pulmonary alveoli (lungs) inner and middle ear blood and lymphatic vessels heart serous cavities endothelium - Answer simple squamous epithelium lining of vessels and serous cavities (surround organs). simple cuboidal epithelium - Answer cube like cells- top view: hexagon nucleus in the center protection/covering for an organ contributes to secretion simple cuboidal epithelium- location - Answer lines ducts of various glands eg. salivary glands simple columnar epithelium - Answer rectangular- top view: hexagon nucleus near base function: protection, secretion/absorption due to goblet cells may/ may not be ciliated on surface - carries mucous and debris towards exterior simple columnar epithelium- location - Answer Non-ciliated: stomach large/small intestine lining of cervical canal Ciliated: uterus fallopian tubes ductus deferens lungs pseudostratified columnar epithelium - Answer crowded columnar cells nuclei- at different levels moisten, warm and clean lining membranes ciliated/ non ciliated pseudostratified columnar epithelium- location - Answer Upper respiratory tract including nasal cavity/ para nasal sinuses stratified squamous non-keratinized epithelium: location - Answer Buccal/alveolar mucosa Ventral part of tongue (underneath) Soft palate Floor of the mouth Sulcular epithelium Esophagus Cornea stratified squamous keratinized epithelium - Answer on dry surfaces keratin layer for protection differentiation among its 5 layers: stratum basal spinosum granulosum lucidum (not in oral cavity) corner (dead, non-nucleated) keratin - Answer tough fibrous, opaque, waterproof protein resists friction impervious to bacteria and other invaders 1st line of defence nuclei are condensed/ inactive