Hole`s Human Anatomy and Physiology Chapter 3
Transcription
Hole`s Human Anatomy and Physiology Chapter 3
PowerPoint Lecture Outlines to accompany Hole’s Human Anatomy and Physiology Tenth Edition Shier w Butler w Lewis Chapter 3 Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. 3-1 A Composite Cell • Is a hypothetical cell • Cells are differentiated (suited for their particular purpose) • Examples • Neurons • Muscle cells • Sperm • Egg 3-3 Cells….. • 3 Fundamental pieces needed in a cell – Plasma membrane: • phospholipid bilayer • Proteins • Cholesterol – Cytoplasm • Everything within the cell membrane except for – Nucleus • Contains hereditary information Cell Membrane • outer limit of cell • controls what moves in and out of cell • selectively permeable • phospholipid bilayer • water-soluble “heads” form surfaces • water-insoluble “tails” form interior • permeable to lipid-soluble substances • cholesterol stabilizes the membrane • proteins • receptors: receive information • pores, channels, carriers: allow materials to pass through • enzymes: speed up chemical reactions • CAMS: cell adhesion molecules • self-markers: ID the cell as part of the organism 3-4 Cell Membrane 3-5 • The Fluid mosaic model – The components of the cell membrane are all moving randomly, switching positions Intercellular Junctions Tight junctions • close space between cells • located among cells that form linings Desmosomes • form “spot welds” between cells • located among outer skin cells Gap junctions • tubular channels between cells • located in cardiac muscle cells 3-6 Cell Adhesion Molecules • guide cells on the move • selectin – allows white blood cells to “anchor” • integrin – guides white blood cells through capillary walls • important for growth of embryonic tissue • important for growth of nerve cells 3-7 Movements Into and Out of the Cell Passive (Physical) Processes • require no cellular energy • simple diffusion • facilitated diffusion • osmosis • filtration Active (Physiological) Processes • require cellular energy • active transport • endocytosis • exocytosis • transcytosis 3-14 Simple Diffusion • movement of substances from regions of higher concentration to regions of lower concentration • oxygen, carbon dioxide and lipid-soluble substances 3-15 Facilitated Diffusion • diffusion across a membrane with the help of a channel or carrier molecule • glucose 3-16 Cells and Solutions • Cells have many materials dissolved in their cytoplasm, as does the extracellular environment around the cell. Water may move in or out of the cell in response to the concentration of these materials, called solutes. Nature works to dilute solutions by moving water where there is a high concentration of solute and low water in comparison to an adjacent area. Solutions • Solvent: does the dissolving – usually water in living things • Solute: gets dissolved in the solvent – can be just about anything, but common ones include • Salts • Ions • sugars Tonicity • Hypertonic: when the solute concentration is higher than the surrounding environment • Hypotonic: when the solute concentration is lower than the surrounding environment • Isotonic: when the solute concentration is the same as the surrounding environment Osmosis • movement of water through a selectively permeable membrane from regions of higher concentration to regions of lower concentration • water moves toward a higher concentration of solutes 3-17 Cells and Solutes (a) A cell is placed in a hypertonic solution; cell shrinks (b) A cell is placed in a hypotonic solution; cell swells Osmosis & Pressure Osmotic Pressure – ability of osmosis to generate enough pressure to move a volume of water Osmotic pressure increases as the concentration of nonpermeable solutes increases • hypertonic – higher osmotic pressure • hypotonic – lower osmotic pressure • isotonic – same osmotic pressure 3-18 Tonicity and RBCs hypertonic – higher osmotic pressure: cells shrink isotonic – same osmotic pressure: cells remain the same size hypotonic – lower osmotic pressure: cells swell Filtration • smaller molecules are forced through porous membranes • hydrostatic pressure important in the body • Ex: molecules leaving blood capillaries 3-19 Active Transport • carrier molecules transport substances across a membrane from regions of lower concentration to regions of higher concentration • sugars, amino acids, sodium ions, potassium ions, etc. 3-20 Endocytosis • cell engulfs a substance by forming a vesicle around the substance • three types • pinocytosis – substance is mostly water • phagocytosis – substance is a solid • receptor-mediated endocytosis – requires the substance to bind to a membrane-bound receptor 3-21 Endocytosis 3-22 Exocytosis • reverse of endocytosis • substances in a vesicle fuse with cell membrane • contents released outside the cell • Ex: release of neurotransmitters from nerve cells 3-23 Transcytosis • endocytosis followed by exocytosis • transports a substance rapidly through a cell • Ex: HIV crossing a cell layer 3-24 Questions you must answer. You may use the transport mechanisms animations on the Bio II page to do so. When asked to compare and contrast, things you may want to think about include: Think in terms of types of materials involved (size, polarity, etc), energy (ATP) use, and how things get in/ out of the cell (protein channels and the types of channels vs. using the membrane itself). • Answer these questions in the appropriate place in your notes packet. PowerPoint Lecture Outlines to accompany Hole’s Human Anatomy and Physiology Tenth Edition Shier w Butler w Lewis Chapter 3: Part II Organelles Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. 3-1 Endoplasmic Reticulum Endoplasmic Reticulum • connected, membrane-bound sacs, canals, and vesicles • Connected to nucleus • Communicate with the cell membrane • transport system 3-8 (ER) • rough ER • studded with ribosomes • protein and lipid synthesis • smooth ER • lipid synthesis • break down of drugs • Break down of lipids • Cell with many ER would be those responsible for making proteins, as well as those that are used to break down drugs • Products of ER used to make new cell membrane pieces 3-8 Ribosomes • free floating or connected to ER (rough ER) • site of protein synthesis (link AAs to form proteins) • Made from proteins and RNA (rRNA) 3-8 Golgi Apparatus/ Bodies • group of flattened, membranous sacs (cisternae) • Connect to the ER (which coming out of the nucleus) • packages and modifies proteins (adds carbohydrates, lipids etc as needed) 3-9 Golgi • Pieces bud off and become vesicles that can release contents to the cell (vesicle trafficking) or outside of the cell (secretory vesicles that break out) • Common in white blood cells and liver cells, or those that make protein hormones (like insulin) 3-9 Golgi • Pieces bud off and become vesicles that can release contents to the cell (vesicle trafficking) or outside of the cell ( secretory vesicles that break out) • Common in white blood cells and liver cells, or those that make protein hormones (like insulin) 3-9 Mitochondria • membranous sacs with inner partitions • generate energy by making ATP from sugars and oxygen (from the foods we eat as well as the air we breathe) • “Powerhouse” of the cell 3-9 Mitochondria • double membrane bound structure • Inner membrane folds are the cristae, which have enzymes on them and control the chemical reactions that release energy (ATP) • The stuff in between the fold is the matrix 3-9 Mitochondria • Have own DNA • Get mitochondrial DNA from mom only (mitochondrial Eve- tracing ancestors) • Possible once a primitive cell Resemble bacteria ? Bacteria taken into cells? Typical cell has 1700 mitochondria; more in cells that need a lot of energy (like muscles) 3-9 Lysosomes Lysosomes • enzyme-containing sack • Sack of membrane • digest worn out cell parts or unwanted substances by using enzymes (40 types, at least) • Called the “suicide sack” because breaking it open would digest cell contents 3-10 Peroxisomes Peroxisomes • sacks of phospholipid membrane • break down organic molecules (like drug, alcohol, or food molecules) by using enzymes • Peroxidases- make hydrogen peroxide (H2O2) when breaking down molecules • H2O2 is destructive to cells so must be removed • Catalase- breaks down hydrogen peroxide • 40 other types • Abundant in liver 3-10 Centrosomes Centrosome • two rod-like centrioles (made from proteins) • used to produce cilia and flagella • distributes chromosomes during cell division (mitosis) in animal cells 3-10 Cilia Cilia • short hair-like projections • propel substances on cell surface • In respiratory tract (Smoker’s cough) • Lining of fallopian tubes to propel egg • In bacteria, they move the cell around 3-11 Flagellum Flagellum • long tail-like projection • Made from microtubules • provides motility to sperm Animation link 1 Animation link 2 3-11 Vesicles Vesicles • membranous sacs (phospholipid membrane) formed from • Pinched in pieces of cell membrane • Pieces of Golgi or ER that have broken off • store substances (can be just about anything- water, nutrients, enzymes, other proteins or substances that the cell has made) 3-12 Microfilaments and Microtubules Microfilaments (smaller) and microtubules (larger) • thin rods and tubules of protein • support cytoplasm • Give shape, structure • allows for movement of organelles (pull organelles around- like “ Mr. Gadget arms” • Important during mitosis/ meiosis • animation 3-12 Inclusions Inclusions • Chemicals in the cytoplasm • Stored nutrients • Glycogen, lipids • Temporary- will go in or out over time • Ex: melanin in skin- a tan goes away over time 3-12 Cell Nucleus • control center of cell; involved with directing the cell when to make certain materials (usually proteins) • Surrounded by a • nuclear envelope • porous double membrane • (phospholipid with over 1000 types of proteins) • separates nucleoplasm from cytoplasm • Allows mRNA out to make proteins (translation) • Controls entry into and exit out of the nucleus 3-13 Cell Nucleus • nucleolus (little nucleus) • dense collection of RNA and proteins • At least one per nucleus • site of ribosome production • Larger if protein making cells • Nucleoplasm • The goo that is in the nucleus and nucleolus 3-13 Cell Nucleus • chromatin (colored substance) • fibers of DNA and proteins (histones) • Look like “beads on a string” • stores information for synthesis of proteins 3-13 • First animation • From the nucleus to the golgi bodies • Overall cell review of organelles Links to animations, ect Diffusion links: • http://www.biosci.ohiou.edu/introbioslab/Bios170/diffusion/Diffusion.html Osmosis Links: • http://zoology.okstate.edu/zoo_lrc/biol1114/tutorials/Flash/Osmosis_Animation.htm • http://lewis.eeb.uconn.edu/lewishome/applets/Osmosis/osmosis.html Interactive cellular transport: • http://www.wiley.com/legacy/college/boyer/0470003790/animations/membrane_transport/ membrane_transport.htm • http://www.connect.ab.ca/~lburns/students_tenunit2note.html Interactive tutorial/ Quizzes • http://science.nhmccd.edu/biol/osotutor.html The image cannot be displayed. Your computer may not have enough memory to open the image, or the image may have been corrupted. Restart your computer, and then open the file again. If the red x still appears, you may have to delete the image and then insert it again. Cell links… • Cell structure:comparisons between cell types http://www.wiley.com/legacy/college/boyer/ 0470003790/animations/cell_structure/ cell_structure.htm • Cell structure and function http://www.wisc-online.com/objects/index.asp? objID=AP11403 (right click on the here to start, and select play) Just some good animation links • http://www.stolaf.edu/people/giannini/ biological%20anamations.html • http://science.nhmccd.edu/biol/bio1int.htm