TCDHA Histology & Embryology Sem 1 Test 1 Questions With Correct Answers

Exocytosis - Answer release of substances out a cell by the fusion of a vesicle with the membrane. Endocytosis - Answer Uptake of materials into the cell Endocytosis: Pinocytosis - Answer "Cell drinking" Endocytosis: Phagocytosis - Answer "Cell eating" Cell Membrane "Plasma Membrane" - Answer Surrounds the cell Composed of phospholipid & protein Semi-permable - Answer provides a selective barrier that regulates transport of substances into and out of the cell. Cytoplasm "Cytosol" - Answer Clear liquid enclosed in the cell Includes: Vacuoles & Vesicle Vacuole - Answer Big "vesicle" Store water & waste Storage sacs Helps regulate the amount of liquid in the cell Vesicles - Answer Small membrane sac Storage & transport Carrying protein & some material Store various neurotransmitters Nucleus - Answer Largest, densest organelle Production of: DNA: cell's genetic information RNA: carries info from the DNA to sites of actual protein synthesis in the cytoplasm "Present in all cells except mature RBC and blood platelets" Nucleolus - Answer Contained in Nucleus Nuclear body that assembles ribosomes Produces rRNA & nucleotides Chromatin - Answer -Contains chromosomes -Looks like diffuse stippling when cell is viewed at lower-power microscopically -complex of DNA & protein -function is packaging very long DNA Nucleoplasm - Answer Fluid portion that contains important proteins Nuclear envelope - Answer Doubled layered membrane Nuclear pores - Answer small holes in the nuclear envelope Allow transport of Rna & ribosomal proteins moving from nucleus to cytoplasm Endoplasmic Reticulum - Answer "Highway system" Rough ER & Smooth ER Contains ribosomes Ribosomes - Answer "Protein Factories" Composed of protein and RNA which synthesize protein Golgi apparatus - Answer "Processing & packaging center" Fxn: sorts, condense, packages & delivers proteins from RER Mitochondria - Answer "Powerhouse of the cell" Release energy from food molecules & transform energy into ATP ( adenosine triphosphate) Lysosomes - Answer "Sewer system" Destroys worn cell parts Produced by golgi apparatus Contains hydrolytic & digestive enzymes capable of digesting substance that enter cells Cytoskeleton - Answer Give basic stability to the cell as a whole, functioning like reinforced girders Also compartmentalizes( sorts out) the cytoplasm, creating preferred "freeways" for the movement of molecules formed by cellular processes Microfilaments - Answer Cell motility Delicate, threadlike Specialized protein, arranged in meshwork bundles Microtubules - Answer Thick & stiff hollow tubes that make up the cilia, flagella, centrioles and spindle fibers. Form cell's internal skeleton Maintain the shape of the cell intermediate filaments - Answer Various type of thicker,threadlike . Involved with intercellular junction & mitosis Inclusions - Answer Metabolically inert substances that are transient over time in the cell. Consist of cellular products that remain in a cell only temporarily. *store lipids & melanin Intercellular Junctions - Answer The connections between one cell and the other Tight Junction - Answer Fuses cell membranes "water tight seal" Prevents the movement of loss of fluid Location: Cells that line inside of the small intestine Gap Junction - Answer Form tubular channels btw cells that allow substance to be exchanged Location: muscle cells of the heart Digestive tube Desmosomes - Answer Attach adjacent cells to each other "Spot Welds" Location: Outer skin Oral mucosa Hemidesmosomes - Answer Attachment of cell to an adjacent non-cellular surface Used in attachment of epithelium to connective tissue *allows gingival tissue to adhere to the tooth surface by epithelial attachments Interphase - Answer Stage in the life cycle when a cell grows & forms new organelle 3 phases: G1: initial resting phase of cell growth S: DNA replication (chromatin & centrosome replication) G2: second resting phase of cell growth Mitosis - Answer Continuous process during which the nuclear parts of a cell are divided into 2 equal daughter cells Stages: Prophase Metaphase Anaphase Telophase Prophase - Answer Chromatin condenses into chromosomes *replicated centrioles move to opposite poles *nuclear membrane & Nucleolus disappear Metaphase - Answer Chromosomes become arranged midway btw the centrioles *spindle fibers from the centrioles become attached to the centromeres of each chromosome Anaphase - Answer Centrioles split & each chromosome separates into 2 chromatids Chromatids migrate to opposite poles by the mitotic spindle Spindle fibers shorten Telophase - Answer Division into 2 daughter cells *nuclear membrane appear around each chromosome set Nucleoli appear Microtubules disappear Meiosis - Answer Occur during the maturation of sex cells Cytoplasmic Division - Answer "Cytokinesis" Which cytoplasmic components of the cell are divided into 2 identical daughter cells following mitosis Differentiation - Answer the process by which cells become specialized Histology - Answer the study of the microscopic structure and function of tissues Tissues - Answer Groups of cells with a common structure and function. Epithelial Tissue - Answer Forms Protective covering Function: secretion & sensory Highly degenerative Tightly joined by desmosomes & hemidesmosomes Act as a barrier Connective Tissue - Answer Provides support for softer body parts Binds structure together Muscular Tissue - Answer responsible for producing body movement Nerve tissue - Answer Specialized to conduct impulses that help control & coordinate body activities Embryological cell Layers - Answer Ectoderm = skin & oral mucosa Endoderm = respiratory & digestive tract Mesoderm = urinary tract What is turn over time & how many days for skin/oral mucosa - Answer Skin = 27 days Oral mucosa = 14 days Epithelium is vascular or avascular? - Answer Avascular = no own blood supply Epithelium: Cell Shapes - Answer squamous - flat cuboidal - cube columnar - rectangular Transitional - changes shape Epithelium: Cell Arrangement - Answer Simple - 1 cell layer Stratified - 2 or more cell layers Pseudostratified -1 layer but looks like 2 Simple Squamous Epithelium - Answer Very thin, flat cells, vary in shape. Covers connective tissue Performs a filtering function on moist surfaces. Location: pulmonary alveoli (lungs) inner and middle ear blood and lymphatic vessels heart serous cavities