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Human Anatomy and Physiology. Chapter 3 –Cells and Tissues. Part I-Cells. Identified by _______________first as he looked at dead cork cells
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Human Anatomy andPhysiology Chapter 3 –Cells and Tissues
Part I-Cells • Identified by _______________first as he looked at dead cork cells • Made of primarily 4 elements---_____________/other elements include Ca, I, Na, K..Some of these in water solution carry a charge ,at which point they are called_______________...Ca is used for blood clotting ,Fe to make hemoblobin, and I for Thyroid hormone C,H,O and N Robert Hooke electrolytes
~60% water/cells are in a dilute water solution called____________________________,derived from blood-HERE IS WHERE EXCHANGES BETWEEN CELLS & BLLOD TAKE PLACE! • Size ranges—2 micrometers-~1 meter • Overall structure may be related to function Interstitial fluid
ANATOMY of GENERALIZED CELL- • -nucleus,cytoplasm,plasma membrane • 1) Nucleus-____________-contains DNA which has info for making proteins-shape usually conforms to shape of cell • ___________or___________ fluid –filled space with nuclear pores penetrate through envelope-Contain jellylike nucleoplasm-other Nuclear elements suspended • _________-makes ribosomes • Chromatin-DNA and chromatin that constitute dense chromosomes during cell division Nuclear envelope OR membrane nucleoli Control center
2)Plasma Membrane(cell membrane) • Contains a phospholipids bilayer-“tail-to-tail” and proteins floating amidst this.-some having attached sugars---as channels to allow particles in and carb tags to specify what molecules are admitted/some proteins act as carriers to move something out membrane • Also contains cholesterol-helps keep the membrane fluid • Proteins may be enzymes or hormone receptors
Plasma membrane cont’d • Polar heads of bilayer are Hydrophilic-______________________ • Nonpolar tails are Hyrdrophobic-avoid water • General properties allows membrane to reseal easily Attracted to water
The “sugar proteins” are _____________________ producing the sugar rich or(sticky) known as Glycocalyx—-one of the many functions is to determine blood type,or as receptors for bacteria,viruses and toxins---see cancer connection p.68 Glycoproteins
Cell Membrane specializations: • Microvilli-Projections to increase surface area so absorption occurs more quickly
Membrane junctions 1-________________-impermeable and bind to prevent leakage between cells(acts like a “zipper”) 2-____________anchoring junctions that prevent mechanical stress(eg.skin cells)-prevent being pulled apart—thickenings_PLAQUES-of adjacent cell membrane-by protein filaments-”guy wires” TIGHT junctions Desmosomes
Membrane Junctions cont’d • 3---______________________-(in heart and between embryonic cells)—function for communication----place where chemicals pass----connect to neighboring cell by CONNEXONS(hallow cylinders composed of proteins to span width between cell) Gap Junctions
CYTOPLASM-material outside nucleus and inside cell membrane 1)cytosol fluid;2)organelles 3) inclusions-chemicals possibly present,depending on cell type—usually stored nutrients of cell products-eg.pigment or glycogen
ORGANELLES: • Most membrane bound • _______________-changes shape and has a double membrane-Inner cristae composed of enzymes and as well as dissolved in fluid-CARRY OUT CELLULAR RESPIRATION from which we get ATP-energy----many found in liver and muscle mitochondria
____________-have rRNA and mRNA is read here-tRNA-brings appropriate amino acid in to make PROTEINS…..some free in cytoplasm and some attached to ER • ER-endoplasmic reticulum-has fluid filled cisterns or coils ribosomes
Er cont’d • Rough-has ribosomes and sends proteins out as their intricate folding occurs to area of cell in transport vesicles or for export • Smooth-used in lipid metabolism and detox of drugs etc.,(many in liver) • ___________-stack of membranous sacs and exports proteins in SECRETORY VESICLES,then to plasma membrane-eg-digestive enzymes made by pancreas GOLGI
______________________-membranous bags w/ digestive enzymes-for worn out cell structures lysosomes
Perioxisomes-membranous sacs w/ oxidase enzymes that use O2 to detox poisons-like alcohol----also to convert FREE RADICALS to H2O2 and this is catalyzed to water….(What are Free radicals?-reactive chemicals w/unpr’ed electrons that can scramble proteins and nucleic acids….many in liver and kidney) • Cytoskeleton—network of protein structures,inc: • Intermediate filaments-help desmosomes • microfilaments-involved in motility and shape- • microtubules-give shape and for cell divisions
Centrioles-near nucleus-role in cell division • Cilia-on some cells to move things-as in respiratory tract • Flagella-whiplike---in sperm
CELL DIVERSITY-Trillions of human cells spell about 200 different cell types.Below are some of the specializations • 1) Cells that connect body parts: • ____________-elongated shape;secretes cable –like fibers;much ER and large Golgi to secrete proteins • ____________(RBC)carries O2 in blood;concave shape gives surface area for O2 uptake,yet streamlined for flow-absent of other organelles so can carry much O2 Erythrocyte Fibroblast
2)Cell that covers and lines body organs: • _______________________hexagonal shape-allows packing together in a sheet;filaments present to resist tearing • 3) Cells that move organs and body parts: • Skeletal and smooth muscle-long and filled w/ contractile filaments-to move bones or change size of internal organs. epithelial
4) Cell that stores nutrients • ____-large spherical shape-from large lipid droplet in cytoplasm • 5) Cell that fights diseases: • ________________________-phagocytic-sends pseudopods to reach infection and infection digested by lysosomes fat Macrophage
6)Cell that gathers info and controls body functions: • ______________-(neuron)-long extensions for receiving messages and transmitting;extensive plasma membrane • 7) Cells of Reproduction: • __________female-largest cell in body • __________male-long and flagellated Nerve Oocyte and sperm
III. CELL PHYSIOLOGY--for metabolism,digestion,waste disposal,reproduction,growth,movement,and irritability • ---MEMBRANE TRANSPORT • Solution basics- • __________=homogeneous mixture of 2 or more substances • _______________-does dissolving • _______________-gets dissolved solvent solution solute
__________________-nucleoplasm and cytyosol---containing sm amounts gases(O2 and CO2),nutrients,and salts in water solution • _____________-continously washes exterior of cells---many components,inc. amino acids,sugars,fatty acids ,vitamins/regulatory hormones and neurotransmitters,as well as salts and waste.CELL MUST OBTAIN THAT WHICH IT NEEDS FROM HERE AND REJECT REST. Interstitial fluid Intracellular fluid
Plasma Membrane is ___________________________________-choosy in what is allowed in and kept out….also certain substance smust remain in cell Selectively permeable
Movement in 2 ways: • 1) PASSIVE TRANSPORT—pass w/o energy • ________________molecules move AWAY from areas where more concentrated;move down concentration gradient;hydrophobic portion of membranes resists diffusion,but particles small enough will go through pores-in MEMBRANE PROTEINS-This is simple diffusion-either they are small enough or lipid soluble diffusion
_____________-water diffuses through selectively permeable membrane-water resisted through nonpolar lipid core-- by pores called____________-made by membrane proteins osmosis aquaporins
Facilitated diffusion-needed substance-eg.glucose-lipid insoluble and too big for pores protein membrane channel is used-transport vehicle • ____________-water and solutes forced through a membrane-or capillary wall by FLUID_HYDROSTATIC PRESSURE---usually by blood-is w/ a gradient,but the gradient actually MOVES the solution.The gradient is called a PRESURE GRADIENT….also used in kidney function Filtration
2) ACTIVE TRANSPORT PROCESSES-uses ATP-particles may be against gradient,too large,or lack a helper protein • Active Transport-solute pump-ATP energizes protein carriers(solute pump)-carries amino acids,sugars ,and most ions----Sodium potassium pump vital to nerve transmission{excess Na ions outside and excess K on inside
exocytosis • ______________________-w/ use of ATP moves large masses in or out(w/o crossing plasma membrane) • __________________- moves large masses out-package by golgi into vesicles and ruptiures outward • __________________-moves the same IN—sends to lysosome…..Phagocytosis-eats bacteria and dead cell bodies • Pinocytosis—pinches in liquids • Receptor mediated endocytosis-plasma membrane receptors target certain molecules Vesicular transport endocytosis
During interphase,cell must duplicate DNADNA REPLICATION/enzyme regulated—remember A_T and C_G
MITOSIS-number of chromosomes you start with—diploid is same at end,then followed by cytoplasm division-____________________ • PROPHASE-chromatin coils and shortens-CHROMOSOMES;centrioles move to opposite poles and mitotic spindle form to form a railway for chromosome movement cytokinesis