California State Standards 1. Cell biology • Cells are enclosed in semipermeable membranes that regulate their interactions with their surroundings • Know prokaryotic cell differ from eukaryotic cells • Know the role of endoplasmic reticulum and golgi apparatus in the secretion of proteins • Students know the role of mitochondria in making stored chemical-bond energy available to cells j. Students know how eukaryotic cells are given shape and internal organization by a cytoskeleton or cell wall or both.
Used compound microscope to look at a slice of cork 7-1 Life Is Cellular A. The Discovery of the Cell 1. Early Microscopes • Robert Hooke- • Anton van Leeuwenhoek- 2. The Cell Theory • Mathias Schleiden- • Theodor Schwann- • Rudolf Virchow- Observed tiny living things in pond water Concluded all plants are made of cells Stated all animals are made of cells Concluded new cells come from existing cells
Cell Theory: cells • All living things are composed of _____ • Cells are the basic units of structure and function in living things • New cells are produced from ____________ Existing cells
Exploring the Cell1. Electron Microscope (TEM & SEM) -Specimen placed in a vacuumhttp://www.mos.org/sln/sem/2. Scanning Probe Microscope -1990 development of fine probe microscope -operates in _______________ -can even show samples in solution ordinary air
0.2 micrometers 1000 micrometers C. Prokaryotes and Eukaryotes • cells vary in size from _________________- ___________________ • viruses are not cells Prokaryotic cell Cell membrane Eukaryotic cell Cytoplasm Cell membrane Cytoplasm Organelles Nucleus
before true DNA Cell membrane Membrane bound organelles Plants, animals, fungi, and protists
Warm-upSection 7-1 • Name 3 scientists and their contribution to science. • What is the cell theory? • What are the characteristics of prokaryotes and eukaryotes. Use the “thinking visually” box on page 173 to answer this question.
Cell Wall Chloroplasts Central Vacuole Venn Diagrams 7-2 Eukaryotic Cell Structure(chart) Section 7-2 Prokaryotes Eukaryotes Nucleus Endoplasmic reticulum Golgi apparatus Lysosomes Vacuoles Mitochondria Cytoskeleton Cell membrane Contain DNA ribosomes Animal Cells Plant Cells Cell membrane Ribosomes Nucleus Endoplasmic reticulum Golgi apparatus Vacuoles Mitochondria Cytoskeleton Centrioles Lysosomes
Smooth endoplasmic reticulum Vacuole Ribosome (free) Chloroplast Ribosome (attached) Cell Membrane Nuclear envelope Cell wall Nucleolus Golgi apparatus Nucleus Mitochondrion Rough endoplasmic reticulum artists rendition of the plant cell Section 7-2 Plant Cell
artists rendition of an animal cell Animal cell
Cell membrane Endoplasmic reticulum Microtubule Microfilament Ribosomes Mitochondrion
Warm-upSection 7-2 • Compare and contrast plant and animal cells. Are they prokaryotic or eukaryotic? • Eukaryotic cells maintain shape and internal organization with ….? • What is the function of the nucleus? • Where is chemical energy from food converted to useable energy? • Where is light energy converted to chemical energy in plants? What is this process called?
enters leaves 7-3 Cell Boundaries A. Cell Membrane • Regulates what ___________ and __________ the cell • Provides • Composed of a ______________ • __________________ are embedded in the bilayer; • _________________ are attached to some of the proteins; allows cells to __________ one another. protection and support lipid bilayer Protein molecules form channels and pumps to move material across the cell membrane. Carbohydrates identify
Outside of cell Carbohydrate chains Proteins Cell membrane Inside of cell (cytoplasm) Protein channel Lipid bilayer CELL MEMBRANE “FLUID MOSAIC” “ID tags” “transport” “Phospholipids”
plants, algae, fungi and many prokaryotes • Cell Walls • Found in • Cell walls are porous enough to allow • Main function is to provide • Plant cell walls made of __________ (carbohydrate fiber) water, oxygen, carbon dioxide easily support and protection for the cell cellulose
C. Diffusion Through Cell Boundaries • All living cells exists in a • Cell membranes regulate • Cell membranes are _____________________ (aka: _______________) • If substances can pass, then the cell • membrane = • If substances cannot pass, then the cell • membrane= liquid environment. the movement of molecules in and out of the cell. selectively permeable semipermeable Permeable impermeable
Water and other substances between the cell membrane and the nucleus. 1. Measuring Concentration • Cytoplasm= • Concentration= • Example:12g salt/3L H2O= 60g salt/3L H2O= • Concentration gradient= mass of solute/volume of solution 4 g/L 20 g/L 5X more concentrated unequal distribution of particles
collide and spread out randomly in solution high to low 2. Diffusion • Particles constantly • Particles move from a _____ concentration _____ a ____ concentration (with the concentration gradient); process is known as _________ • Diffusion continues until • Equilibrium = • Diffusion depends upon random particle movements, substances diffuse across membranes ______ requiring the cell to use _______ diffusion equilibrium is reached When particles are evenly distributed in solution without energy The movement of particles will continue to move equally across the cell membrane to maintain equilibrium.
H2O passes easily across most membranes The diffusion of water through a selectively permeable membrane • Osmosis • Osmosis = Before Osmosis After Osmosis Selectively permeable membrane water solute
1. How Osmosis Works Left Beaker: • More sugar molecules on the ____ side (low water concentration). • The membrane is permeable to water but not sugar. left High water concentration on the right side. Net movement of water from high water concentration to low water concentration.
TYPES OF SOLUTIONS Hypertonic SolutionIsotonic SolutionHypotonic Solution “above strength” “same strength” “below strength” High concentration of Equal concentration of Low concentration of Dissolved substances dissolved substances dissolved substances In Solution in solution
Cells in a hypertonic solution • In a hypertonic solution, water leaves a cell by osmosis, causing the cell to shrink. H2O H2O Water Molecule Dissolved Molecule
Cells in a hypotonic solution • In a hypotonic solution, water enters a cell by osmosis, causing the cell to swell. H2O H2O Water Molecule Dissolved Molecule
Cells in an isotonic solution • In an isotonic solution, the concentration of dissolved substances in the solution is the same as the concentration of dissolved substances inside the cell. H2O H2O Water Molecule Dissolved Molecule
The effects of Osmosis on cells • (animal cells refer to figure 7-16) Cells in a hypertonic solution Cells in a hypotonic solution Cells in an isotonic solution
With the help of protein channels E. Facilitated Diffusion • Molecules, that cannot diffuse across the cell membrane’s lipid bilayer on their own, can move • Molecules still ___________________ concentration move from high to low
Molecule to be carried Energy Molecule being carried againsta concentration gradient (from low to high) energy F. Active Transport • Movement of molecules • Requires • Needs a transport protein or pump
Large molecules and clumps of material can be • taken into the cell by a process known as • ___________. The two kinds of endocytosis are: • 1. Phagocytosis= • 2. Pinocytosis= • ___________= release of large amounts of material endocytosis ‘Cell eating’ ‘cell drinking’ Exocytosis endo/exocytosis demonstration
Transport of Large Particles Section 8.1 Summary – pages 195 - 200 • Endocytosis is a process by which a cell surrounds and takes in material from its environment. Nucleus Digestion Exocytosis Endocytosis Wastes removal
Let’s Review: • interactive sites for cell membrane, diffusion, active, passive transport Simple diffusion (includes Osmosis) Facilitated Diffusion ATP required No ATP No ATP Hi-Lo Hi-Lo Lo-Hi No protein Needs protein Needs Protein
Warm-upSection 7-3 • Describe the anatomy of a cell membrane. • What are the main functions of the cell membrane and the cell wall? • What happens during diffusion? • What is osmosis? • Describe the terms hypotonic, hypertonic, isotonic. • Compare and contrast passive and active transport.
outnumber 7-4 The Diversity of Cellular Life A. Unicellular Organisms (single celled) • Unicellular organisms _________ multicellular organisms • Examples: B. Multicellular Organisms (many celled) • Cells become ___________ to perform different tasks • Cells need to communicate and cooperate Yeast, algae, bacteria specialized
C. Levels of Organization • The levels of organization in a multicellular organism are: individual CELLS TISSUES ORGANS ORGAN SYSTEMS
Group of similar cells that perform a particular function muscle epithelial 1. Tissues= • Four types of tissue: - - - - • Organs= • Ex. bicep muscle is mad of muscle, connective, and nervous tissue 3. Organ Systems= nervous connective Groups of tissues Group of organs that work together to perform a specific function.
Warm-upSection 7-4 • What are the levels of organization in a multicellular organism? • What is cell specialization? Provide 3 examples.