Can You Identify This Object? CELLS Day 1: CELLULAR COMPONENTS & PROCESES What is a cell? Collection of living material enclosed by a barrier that separates the cell from it s surroundings Basic Unit of all forms of Life MODERN CELL THEORY 1. All living things are made of cells. 2. Cells are the basic unit of structure and function in living things. 3. All cells arise from preexisting cells (cell division). 2 Exceptions to The Cell Theory 1. Viruses (debated whether living or nonliving) 2. Living cells arise from organic matter (nonliving) Famous People Their View On The Cell Theory 1
Anton Van Leewenhoek 1632-1723, Dutch Discovered tiny organisms - bacteria and protozoa. - blood cells - living sperm cells of animals - round worms. Robert Hooke 1663, English scientist Observed cell walls from cork cells (dead cells). Observed insects (flea) Came up with the word- CELL from tiny rooms called monasteries Made over 500 microscopes. Robert Brown 1833, Scottish Discovered the nucleus when studying flowers. Mattias Schleiden 1839, German All plants are made up of cells. Studied the function of the nucleus & other cell bodies. Recognized the difference between unicellular & multicellular organisms. Theodor Schwann 1839, German All animal tissues are made up of cells. Came up with the term cell theory Developed the word metabolism (chemical reactions in living tissue). Rudolf Virchow 1821-1902, German Stated: Every cell arises from another cell. Believed that disease involves changes in normal cells. 2
Lynn Margulis 1938 American Biologist Origin of eukaryotic organelles Endosymbiotic theory about how certain organelles were formed Day 2 Prokaryotic & Eukaryotic Cells 2 Types of Cells 2 Types of Cells Prokaryotic Eukaryotic Prokaryotic Eukaryotic o Simple function o Single-celled organisms o Complex Function o Multi-cellular organisms Ex: Bacteria Blue-green algae Ex: Humans Yeast o No Nucleus o Have a Nucleus o No other Cell organelles o Have organelles Unicellular Organisms: Any plant or animal that has a single cell. Ex: amoeba (E) Blue-green algae (P) bacteria (P) fungi (E) protozoa (E) yeast (E) Multi-cellular Organism o Organisms that have more than 1 cell. o Cells specialized for a particular function (specialization). Examples: humans, hydra 3
Which is a Prokaryotic & a Eukaryotic Cell? Organelles Little organs of the cell Present in BOTH plants and animals Carry out cellular functions! Animal Cells: (Eukaryotic) The parts of a cell that carry out a function are called cell: ORGANELLES Nucleus Nucleolus Mitochondria Golgi Body Complex Endoplasmic Reticulum Vacuole Lysosome Centrioles (ANIMAL ONLY) Plant Cells have all of the above &: Cell Wall Chloroplast Prokaryotic or Eukaryotic What Are Humans? What Are Viruses? Genetic information surrounded by a protein coat. Require a host cell to reproduce. Ex: Polio, Influenza, Chickenpox What Are Plants? 4
Question: Which of the following is not alive, but requires life to be able to reproduce? A. Bacteria B. Fungus C. Protozoa D. Virus Draw a Venn Diagram: Use Notes from class work to complete. Hint For Completing Venn Diagram Day 3: Group Work o Review H.W sheets o Handout PPT. packet identify the structure & function of cells using textbook. http://www.cellsalive.com/toc_cellbio.htm Activity 4 6 3 2 Day 4 LABEL 1 1. 2. 5 Computer Tutorial: Cell Structure & Function 3. 4. 5. 6. 7. 7 http://www.biologydaily.com/biology/cell_nucleus 5
Answers Drawing of nucleus and the endoplasmic reticulum. (1) Nuclear membrane (2) Ribosomes (3) Nuclear pore complexes (4) Nucleolus (5) Chromatin (6) Nucleus (7) Endoplasmic reticulum What Are Viruses? Genetic information surrounded by a protein coat. Require a host cell to reproduce. Ex: Polio, Influenza, Chickenpox The whole structure is surrounded by. http://www.biologydaily.com/biology/cell_nucleus Question: Which of the following is not alive, but requires life to be able to reproduce? A. Bacteria B. Fungus C. Protozoa D. Virus Nucleus Control center Controls cell activity Contains hereditary material Nucleus Nuclear membrane Double membrane that surrounds the nucleus. Selective Permeablilty (selects material entering or leaving) Has pores (openings) 6
Nuclear membrane Nucleolus Nuclear Round organelle in the nucleus. The site for **protein synthesis** (production). http://www.tvdsb.on.ca/westmin/science/sbi3a1/cells/nucleus.htm Nucleolus Ribosomes Tiny structures Located in the cytoplasm, endoplasmic reticulum, or nucleus. Production of proteins which are important for cellular growth & reproduction. Chromatin- long thin strands of DNA that control cell metabolism and heredity Ribosomes RIBOSOMES Endoplasmic reticulum (ER) Storage, synthesis, and transport of proteins within the cell. HIGHWAY for cell transport. http://www.ibiblio.org/virtualcell/textbook/chapter3/cyto1b.htm 7
Endoplasmic reticulum (ER) Endoplasmic reticulum (ER) Two Types 1. Rough Endoplasmic Reticulum - Has ribosomes 2. Smooth Endoplasmic Reticulum - No ribosomes Cytoplasm (protoplasm) Fluid like material in the cell over 80 % water HOLDS cell organelles in place site for cellular chemical reactions Cytoplasm (protoplasm) Vacuole Membrane bound cytoplasmic spaces containing materials. Two Types: Vacuole Food vacuole--store and digest ingested food Contractile vacuole-pumps excess water from cells maintaining homeostasis 8
Plant Cell Vacuole Vacuole Animal Cell: Amoeba Contractile Vacuole Food particles Food Vacuole Cell (Plasma) Membrane A bilayer lipid surrounding nucleus. "Fat sandwich Is SEMI-PERMEABLE Selectively regulates the flow of materials to and from the cell to maintain chemical homeostasis. Lysosome Small round membrane (pouch) containing digestive enzymes. Digest bacteria and foods. Lysosome Mitochondrion "Powerhouse of the cell" Carries on cellular respiration (contains respiratory enzymes that make ATP) (energy molecule). 9
Mitochondrion Mitochondrion Mitochondria: Cellular Respiration Golgi apparatus (complex) Synthesizes, packages, and secretes cellular products for STORAGE & later use. Packages waste & harmful materials. Golgi Apparatus Cytoskeleton Protein filaments for shape and allow movement within the cell. Microtubules http://kentsimmons.uwinnipeg.ca/cm1504/nucleus.htm Microfilament (Actin) 10
Activity: Label 1-13 1 13 Wrap Up: ANIMAL CELL Answers Animal cell- Organelles: (1) Nucleolus (2) Nucleus (3) Ribosome (4) Vesicle (5) Rough endoplasmic reticulum (ER) (6) Golgi apparatus (7) Cytoskeleton (8) Smooth ER (9) Mitochondria (10) Vacuole (11) Cytoplasm (12) Lysosome (13) Centrioles Animal Cell ANIMAL CELL ORGANELLE ONLY Centriole Cylindrical structure in the cytoplasm. Functions during cell division. Centrioles Plant Cell 11
PLANT CELL ORGANELLES ONLY Cell Wall Cell Wall Surrounds cell Made mostly of cellulose Gives structure & support Cell Wall Chloroplasts: Plant Cell Chloroplasts Green in color Double membrane that contains the green pigment chlorophyll which carries on photosynthesis. Uses the sun s energy to make food for the plant. Photosynthesis Chlorophyll converts light energy to chemical energy in the chloroplasts. Overall Net equation for photosynthesis: 6 Water + 6 Carbon dioxide glucose + 6 oxygen (when catalyzed by chlorophyll in the presence of sunlight) Questions: Answer in Notebook 1. What are ribosomes made of? Proteins & RNA 2. Where are ribosomes made or produced? Nucleolus 3. What do ribosomes produce or manufacture? Proteins 4. Where are ribosomes found? Cytoplasm, Nucleus, ER Where do these functions take place? RNA synthesis = Nucleolus Protein synthesis = Ribosomes 12
Extra Slides Cell (Plasma) Membrane A bilayer lipid surrounding nucleus. "Fat sandwich Is SEMI-PERMEABLE Selectively regulates the flow of materials to and from the cell to maintain chemical homeostasis. Cell (Plasma) Membrane Cell (Plasma) Membrane Hydrophilic- attracts water Hydrophobic- repels water Not found in plant cells Cell (Plasma) Membrane 13
Types of transport in Cells 1. Passive transport o Movement of substances through a membrane from a high to a low region of concentration. o No energy needed (ATP) Examples: 1. Diffusion 2. Osmosis 2. Active transport o Movement of substances through a membrane from a low concentration to a region of high concentration. o Requires cellular energy (ATP) o Whether passive or active transport is needed depends on the CONCENTRATION GRADIENT. The concentration gradient is the difference in the concentration of a substance in two different spaces. Concentration o The amount of a particular substance in a contained area compared with the amount of the same substance in another area. Example: Amount of something in a space (water, salt, sugar, iron). 14
PROCESSES OF THE PLASMA MEMBRANE Passive Transport: (Diffusion and Osmosis) Goal- to reach EQUILIBRIUM within the cell for diffusion & osmosis. Equilibrium is a condition in which the movement in one direction is equal to the movement in another direction Diffusion the tendency of molecules to move from an area of higher concentration to an area of lower concentration (concentration gradient- diff in conc. between 2 regions) Osmosis movement of water through a membrane from a region of higher to lower con. Solute - substance being dissolved in a liquid (ex. salt) Solvent - substance doing the dissolving (ex. water) Permeability - the extent to which a membrane will allow particular sized molecules to pass Semi-permeable membrane (selectively permeable)-allows allows some molecules to pass but not others So, describe how Kool-Aid is made with regard to the terms solute and solvent. What is the universal solvent? When comparing two solutions there are three possible relationships, We Identify the relationships by determining what would happen if a cell were placed in the solution. Hypertonic- A solution that causes a cell to shrink because of osmosis. Meaning water leaves the cell. Hypotonic- A solution that causes a cell to swell because of osmosis meaning water rushes into the cell. Isotonic-A A solution that causes no change in cell size. Meaning there is no movement of water. 15
If the fluid outside the cell has Then the outside fluid is Water moves Effect on the cell? less water than is present inside the cell more water than is present inside the cell same amount of water as inside the cell Active Transport- So, answer this question. Why do establishments offer free popcorn, peanuts, and pretzels to their patrons if they are serving beverages? What changes are taking place in the body to initiate the need for more beverages? the movement of a substance against the concentration gradient. (uphill) Active transport requires cell to USE ENERGY Sodium pump - transports three sodium ions out of the cell and two potassium ions into the cell Both are against the concentration gradient The energy needed to perform this activity is supplied by ATP (adenosine tri-phosphate) ATP is a unit of energy made by the cell Endocytosis- the movement of a substance into the cell by a vesicle. A vesicle is a form of packaging that is used by cells. Exocytosis- the movement of a substance out of the cell by a vesicle. Phagocytosis- cytoplasm of cell surrounds and engulfs particle--ex. ameba and white blood cell Pinocytosis- plasma membrane "pinches in" to permit entry of molecules too large to diffuse through 16
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