A&P Chapter 3 Part 1 - Lecture notes 3 PDF

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Biol 2401 with Prof. Vasefi...

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Anatomy & Physiology Chapter 3 (Part 1) -Cell BiologyCell: basic structure & functional unit of living organisms (/) 100 trillion individual cells in human body, 200 distinct types

3 Parts of Cell: (/) plasma membrane- barrier b/t internal & external cell environment involved in movement of substances in & out of cell & cell communication flexible & selectively permeable has phospholipid bilayer which has proteins embedded (integral & peripheral) (/) cytoplasm- has cytosol (ICF) and organelles (/) nucleus- control center, has DNA,

Peripheral Proteins : attached to inner/outer surface of phospholipid bilayer (/) outer surface: glyco protein which bond with carbohydrates

Integral Proteins : actually in phospholipid bilayer Function of Membrane Proteins : (/) ion channels- form pores through which ions can pass through plasma membrane (/) carrier/transport proteins- move molecules (not just ions) by changing shape (/) receptors- bind to ligands (any chemical substance that binds to a receptor) (/) enzymes- catalyze specific reaction in & out of cell (/) anchor proteins- anchors membrane protein of cell to one another cell’s proteins (/) cell-identity markers- identify cell as belonging to body (major histocompatibility protein)

Electrical Gradient: Formed when two molecules of opposite charge separated (/) Creates a tension between the two substances b/t either repel or attract

Membrane Fluidity: phospholipid bilayer in constant motion (/) allows PM to move during growth, maintenance & repair

Plasma Membrane Selectivity: allows some to cross, others not (/) allows small uncharged non polar molecules like carbon & oxygen (/) semi-allows small uncharged polar molecules (water) (/) impermeable to charged large molecules (but ion channels & carrier proteins change this)

Passive Transport: (/) requires no energy input from cell (/) substance moves down concentration/electrical gradient. High-> low

Mechanisms of Passive Transport: (/) simple diffusion- molecules go high low until @ equilibrium: small uncharged nonpolar/polar (/) facilitated diffusion- substances move across plasma barrier by using a protein carrier

Osmosis: diffusion of solvent across selectively permeable membrane (/) permeable to solvent (water) (/) impermeable to solutes dissolved in solvent

Osmotic Pressure: (/) drives water from high water concentration to low water concentration

Anatomy & Physiology Chapter 3 (Part 1) -Cell BiologyDiffusion: slow, inefficient process

Factors that affect diffusion rate: (/) temp: more heat, faster (/) mass of diffusion molecules: smaller, faster (/) steepness of concentration gradient: bigger, faster (/) surface area: smaller, faster (/) diffusion distance: smaller, faster

Tonicity: concentration of solutes inside cell relative to concentration outside of cell (/) ability of a solution to change volume of cell through osmosis

Hypotonic: ECF concentration lower than ICF (/) water enters cell faster than leaves -> cell could burst (lysis)

Isotonic: equal concentration in & out, no net movement Hypertonic: ICF concentration lower than ECF (/) water leaves cell -> crenation

Active Transport: (/) requires some energy input from cell (/) substance can go against gradient

Mechanisms of Active Transport: (/) transport via carrier protein (which can also be in passive if from high to low) (/) transport in vesicles

Primary Active Transport

Secondary Active Transport

energy derived from ATP

energy derived from ion concentration gradient usual Na+

used to change shape of transporter protein. used to change shape of transporter protein EX: Na K pump

Na+ goes down its concentration gradient, releasing energy that is used to pump 2nd molecule against its concentration gradient

Vesicle: small sac formed by budding off from plasma membrane (/) large molecules can move across plasma membrane by being packed in vesicle

Endocytosis: moving substances INTO cells via vesicles. 3 types (/) receptor-mediated: cell takes in ligands, molecules bond to receptor points transports individual molecules, highly specific (/) phagocytosis: cell eats large solid polar molecules has 2 receptor points, highly specific, can bring in larger particle

Anatomy & Physiology Chapter 3 (Part 1) -Cell Biology(/) pinocytosis (bulk-phase): cell engulfs fluid & dissolved solutes

no receptor points involved, unspecific, transports many small molecules Exocytosis: movement of substances OUT of cell via vesicle (/) formed inside cell, vesicle fuses w/t plasma membrane who then dumps contents

Trans-cytosis: movement of substance across cell using vesicles (/) missing link b/t endocytosis & exocytosis

Cytoskeleton: network of protein filaments that extend through cell, 3 parts (/) microfilament small, made of actin, provide structural support & involved in cell movement (/)intermediate filaments medium size, made of several proteins, provide structural support for cell hold nucleus & other organelles in place (/) microtubules large, made of tubulin (protein) molecule, arranged in hollow tubes determine cell shape involved in movement of organelles, chromosomes, cilia and flagella

Centrosome: organization center for mitotic spindle (/) located near nucleus, centrioles, formed by microtubules

Flagella: made of microtubules, project from surface of some cells (/) long & singular, propels cell through fluid

Cilia: made of microtubules, project from surface of some cells (/) numerous & small, involved in ECF movement...