Anatomy & Physiology of Cells Chapters 3 & 4 Anatomy & Physiology

1. Anatomy & Physiology of Cells Chapters 3 & 4 Anatomy & Physiology

2. Basic Cell Info • Cell Theory - the cell is the fundamental organizational unit of life • Schleidon & Schwann – first to suggest that all living things are composed of cells • Human body – _____ _____________ cells • Cell diameter range: 7.5 micrometers (RBC) – 150 micrometers (ovum) • Composite cell – generalized cell illustration we study that exhibits most important characteristics of many different dinstinctive cell types; • no such cell exists in the body • 3 Main Cell Structures: • ___________ _____________ • __________________ (with organelles) • _____________

3. Cytoplasm Chromatin Nuclear pore Plasma membrane

5. Cell Structures • Plasma membrane • Outer boundary of cell • Made of ___________, ____________, and other molecules • ____________ ______________model • molecules slowly float around the membrane • molecules bound tightly to form continuous sheet • molecules bound loosely to slip past one another • Chemical attractions / forces hold membrane together • Phospholipid ___________ • hydrophilic heads - polar • hydrophobic tails - nonpolar • Without _____________________ (steroid lipid), membranes would break easily

6. Plasma Membrane cont. • ____________________ permeable • __________-soluble molecules pass through easily • __________-soluble molecules can not pass through without help • Membrane proteins: • how the cell controls movement of molecules • “gates” that open and close to allow things into and out of the cell • Carbohydrates attached – glycoproteins • ______________________ markers allow to distinguish between normal and abnormal cells • attack bacteria, cancer, blood transfusions • _____________ attached – catalyze cellular reactions • Other proteins attached – form connections between cells • Receptors – react to hormones, etc. to trigger metabolic changes; __________________ transduction

7. Hydrophilic Phospholipid head Integral protein Hydrophobic Phospholipid tail Peripheral protein

9. Nucleus • One of largest cell structures • Occupies ______________portion of cell • Shape and number in a cell vary (most common is one spherical nucleus) • Nuclear membrane - double membrane with pores • contains _____________________ • pores called nuclear pore complex (NPCs) • selectively permit molecules to enter or leave nucleus • extensions of the ________________ • Contains genetic material • forms _______ chromosomes in _____________ cells • Remains as ________________ in ______-dividing cells • Dictates structure and function of the cell • Contains ________________ • nonmembranous • contains RNA • synthesizes ribosomal RNA (rRNA) to combine with proteins to make ribosomes • cells that make more protein have bigger nucleolus

11. Cytoplasm • Gel-like substance that makes up inside of cell • Contains various organelles suspended in ___________________ (intracellular fluid) • _______________ organelles - specialized sacs or canals made of cell membrane • Endoplasmic reticulum • Golgi apparatus • Lysosomes • Peroxisomes • Mitochondria • Nucleus • ____________________organelles - not made of a membrane; made of microscopic filaments • Ribosomes • Cytoskeleton • Fibers – microfilaments; intermediate filaments • Centrosome • Cell extensions – microvilli, cilia, flagella • Nucleolus

12. OrganellesEndoplasmic Reticulum • Flat, curving sacs in parallel rows • Two types • ____________ ER • Contains ribosomes • Extends from ___________ • Protein synthesis and intracellular transportation • proteins move through canals to the golgi • ______________ ER • Synthesizes lipids and carbohydrates • steroid hormones, glycoproteins, membrane lipids

13. Organelles cont.Golgi Apparatus • Membranous • ________________ (sacs) stacked near nucleus • Processes and packages molecules for export from cell • Steps to processing and packaging • ER delivers protein via vesicles • Enters first cisternae • Chemical modifications • Sent to next cisternae via vesicle • Further modification • Repeated until last cisternae • Packaged in secretory vesicle • Migrates to cell surface • Combines with membrane • Secretes contents

14. Organelles cont.Lysosomes & Peroxisomes • Lysosomes • Membraneous sac • Vesicles that pinched off from Golgi • Size and shape change depending on activity • Contains enzymes that if bust can kill the cell • Destroys __________________ • “digestive bags” , “cellular trashcan” • Peroxisomes • membraneous sac • Smaller than lysosome • Contains enzymes (peroxidase, catalase) • _________________ harmful substances • Seen in kidney and liver cells

15. Organelles cont.Mitochondria • Membraneous • _____________ membrane • Form a sac within a sac • _______________ – inner membrane folds • contain enzymes – make ATP • Membranes same structure as plasma membrane • “power house” • Liver - +1000 mitochondria • Sperm cell – 25 mitochondria • Exercise – increases number of mitochondria

16. Organelles cont.Ribosome • Every cells contains thousands • rER and free in cytoplasm • Nonmembranous • Protein synthesis (cell’s “protein factory”) • Ribosomes on ________ – export and cell membrane use • ________ribosomes – make proteins for domestic use • make structural and functional proteins (enzymes) • Large and small _________________ • each has RNA bonded to protein • rRNA

17. Cytoskeleton • 1. Cell’s internal __________________ network • Made of rigid, rodlike pieces (support and movement) • Muscle-like groups of fibers • Twisted protein molecules

18. Cytoskeleton • Cell Fibers • Microfilaments • smallest fibers • serve as “cellular muscles” • muscle cells – proteins slide past each other • Intermediate filaments • slightly thicker than microfilaments • supporting framework • ___________ everything in the cell • dense arrangement in cells on outer skin layer • Microtubules • thickest cell fiber • “_____________” of the cell • move things around in cell • cause movement of entire cell • movement of vesicles • movement of chromosomes in mitoses

19. Cytoskeleton cont. • Centrosome • Non-membraneous • Very _____________ site • Near ___________ • Coordinates building and breaking of microtubules • “______________ organizing center” (MOC) • Important role in cell division • Centrioles found here • form microtubular cell extensions (see next slide) • form _______________ in cell division

20. Cytoskeleton cont. • Cell extensions • Microvilli • found in areas where _________________ is important • increases surface area of cell • allows faster rate of absorption • found in epithelial cells that line intestines • cover surface of cell • contain ____________________ • 100s/cell • Cilia • contain _________________ • main purpose – _________________ • cilia shorter and more numerous than flagella • line respiratory tract; cilia moves mucus to be swallowed • Flagella • contain microtubules • main purpose – movement • Only present in _______ ______

21. Cell to cell contact • Gap junctions • It directly connects the _________ of two cells, which allows various molecules to pass freely between cells. • ______________proteins connect plasma membranes • Desmosomes • ________________ filaments connect plasma membranes • specialized for cell-to-cell adhesion • Ex. Skin cells • Tight junctions • join together the ______________ of adjacent cells. http://www.youtube.com/watch?v=3Xb0PFFGblI

22. PASSIVE Cellular Transport • with concentration gradient • Moves from areas of HIGH to low concentration • Simple diffusion – movement of particles through bilayer from high to low concentration • 3 main categories • Dialysis– diffusion of small solute particles through selectively permeable membrane • Osmosis – diffusion of water • Facilitated diffusion – diffusion of particles through membrane with help of carrier proteins

23. Diffusion • http://highered.mcgraw-hill.com/sites/0072495855/student_view0/chapter2/animation__how_diffusion_works.html • 1. molecules densely packed when enter water • 2. molecules collide in high conc. • 3. gradually move away from each other • toward low conc. • 5. eventually evenly distributed • semipermeable membrane • left – unbalanced • right - homeostasis

25. Dialysis

26. Osmosis Osmotic pressure / tonicity – water pressure that develops in the solution with the higher concentration of impermeable solute (low water concentration) http://highered.mcgraw-hill.com/sites/0072495855/student_view0/chapter2/animation__how_osmosis_works.html

27. Osmosis cont. http://www.coolschool.ca/lor/BI12/unit4/U04L03/osmosis.swf crenation plasmolysis

28. Facilitated Diffusion • Carrier mediated • Attracts solute to binding site • Carrier protein changes shape • Solute can move to other side of memb http://www.coolschool.ca/lor/BI12/unit4/U04L03/facilitated%20transport.swf http://highered.mcgraw-hill.com/sites/0072495855/student_view0/chapter2/animation__how_facilitated_diffusion_works.html

29. ACTIVE Cellular Transport • _____________ concentration gradient • From __________ to HIGH concentration • Uses carrier protein & _______________ • Two main categories • Endocytosis- movement of particles into the cell via secretory vesicles fusing with plasma membrane • Phagocytosis - taking in of __________ particles by vesicles fusing with plasma membrane • “cellular eating” • Pinocytosis– taking in of _____________ particles (fluid) by vesicles fusing with plasma membrane • “cellular drinking • Exocytosis– movement of particles out of the cell via secretory vesicles fusing with plasma membrane

30. Active Transport http://www.coolschool.ca/lor/BI12/unit4/U04L03/active%20transport_jeffedit.swf Carrier protein uses ENERGY to move solute AGAINST conc gradient 3 Na+/2K+

31. Endocytosis http://www.youtube.com/watch?v=DuDmvlbpjHQ

33. Enzymes • Functional ______________ • Catalyst • ____________ activation energy to start chemical reaction • Not changed in reaction or used up • Tertiary/quaternary proteins • Cofactor – inorganic, non protein • Coenzyme – organic, non protein • Active site – part of enzyme where binds to substrate • Lock-and-key model

34. Enzyme Function • ________________Effect • Allosteric effector molecule binds to allosteric site • Active site’s shape is changed • Inhibition or Activation of enzymes • Factors that have allosteric effect • pH • Temp • Cofactors being added/removed • Proenzymes – inactive enzymes • Kinases • synthesize enzymes • Convert proenzyme to enzyme

36. Cell Metabolism • Catabolism • net __________ of energy • Breaks down large molecules into smaller ones • ex. cellular respiration • Anabolism • net ____________ of energy • Build large molecules from smaller ones • ex. synthesizing DNA

37. Cellular Disease • Cystic fibrosis • a. ____ pumps in membrane missing • b. Secretions (sweat, mucus) salty • c. Thick mucus causes lung infection • d. Respiratory & digestive problems • Diabetes mellitus/type 2 • a. Adult onset • b. Non-insulin dependent • c. Obesity onset • d. Reduces ___________ receptors in memb • Cancers • a. Abnormalities in __________ • b. Cause tumors • c. Hyperplasia: increase in number of cells/proliferation of cells • Genetic Disorders • a. Sickle-cell anemia: mutation in _____________________ protein