Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Cells- The smallest units of Life Breast Cancer Cell Cell- basic units of structure and function in living things History 1600’s Anon Van Leeuwenhoek- Dutch Biologist- built first simple microscope -discovered: bacteria, protists, sperm cells, blood cells to name a few Robert Hooke- English Scientist, first to study cells (cork) 1800’s Robert Brown- Scottish, discovered the nucleus CELL THEORY- Based on historical data 1. All living things are composed of cells 2. Cells are the basic structure and function of living things 3. Cells come from other cells Types of cells: Prokaryote- smaller, simplifier cells that do not contain a nucleus. Eukaryotic Organisms have 3 basic structures in common 1. Nucleus 2. Cell Membrane 3. Cytoplasm Prokaryote vs. Eukaryote Nucleus- information center and directs all activities in the cell • where DNA is found • How do Prokaryotes and Eukaryotes differ in terms of the nucleus? • Nuclear Envelope- surround the nucleus • Nuclear Pores- holes in envelope, allows for movement • Nucleolus- ribosome’s are made here • Chromosomes (Chromatin)- long strands of DNA that contain genetic info for reproduction Cell Membrane- surrounds the cell and regulates what enters and exits the cell • adds support and some limited protection • made of phospholipids, Cholesterol- helps maintain structure, Proteins and Carbohydrates • Phospholipids have a charge of 0 and are polar one end + • create a lipid-bi-layer • heads face out, tails in Cytoplasm- jelly-like fluid that the organelles are found in Cytoskeleton- structural element that makes up the cytoplasm • made of 2 main parts • Microtubules- hollow tubes of protein • Organelles can move around the inside of the cell on these • Form centrioles (small set of microtubules) in animal cells • Help move chromosomes around during cell division • In some single celled animals they form cilia and flagella • Microfilaments- smaller than microtubules • Helps with support and organelle movement 1 Mitochondria- where cellular respiration takes place • found in both plant and animal cells • powerhouse of the cell • Where ATP is produced from glucose. 2 Ribosomes- where proteins are assembled • made of RNA and proteins in the nucleolus • smallest of the organelles • can be attached or free • translate mRNA into polypeptide chains • made of 2 subunits • both plant and animals contain ribosomes 3 Endoplasmic Reticulum Smooth- synthesize lipids, detoxify drugs(liver), stores Ca, stores enzymes, and transports Rough- has ribosomes attached to it, modifies proteins from protein synthesis 4 Golgi Appratus- flattened stack of membranes that modifies, collects, packages and distributes molecules • makes lysosomes • last stop for a molecule before it leaves the cell • both plant and animals have these Can you tell the difference between ER and Golgi? 5 Lysosomes-suicide sacs, destroy foreign material and recycle cell parts • found in animals and plants • Tay Sachs Disease- no lysosomes, can’t metabolize fats, builds up in brain (100% fatal) http://highered.mcgraw-hill.com/olc/dl/120067/bio01.swf Animation 6 Chloroplast- site where photosynthesis takes place • found in plants, some protists and some bacteria 7 Cell Wall • protects and supports most cells • only found in plants • very porous • made of polysaccharide – cellulose • has pectin- sticky (polysaccharide), helps hold cells together breaks down to a monosaccharide as fruit over-ripens • wood bearing plants have lignin- makes cellulose rigid 8 Vacuoles- storage sites for water, salts, proteins, and carbohydrates • found in animals and plants but are different sizes 9 Plastids- organelles of storage • Chloroplasts- stores chlorophyll • Chromoplasts- store pigments other than chlorophyll • Leukoplast(Amyloplast)- storage of starches Starch grains in a potato tuber 1. Come up with your analogy 2. Cut out paper in the shape of your analogy 3. Draw a plant or animal cell Cell Movements • cells are surrounded by liquid which makes movement of molecules easier Plasma (Cell) Membrane Types (depends on what is trying to get 1Permeable through 2Semi/Selectively Permeable 3 Impermeable Passive Transport- movement of molecules without the use of energy 1 Diffusion- movement of molecules from areas of high concentration to areas of low concentration until equilibrium is reached 2 Osmosis- movement of water from areas of high concentrations to low concentrations through a semi-permeable membrane until equilibrium is reached. • both work on concentration gradients • phospholipid membrane is permeable to water • Penicillin- disrupts bacterial cell membrane structure and kills by osmotic pressure 3 Facilitated Diffusion- molecules are moved across a membrane by a carrier protein, from high concentration to low concentration • must have a concentration gradient • example: moving glucose into red blood cells Hydrostatic Pressure- known as osmotic pressure, is the pressure of water placed on walls and membranes How do Single Celled Organisms compensate for osmotic pressure 1. minimize contact with fresh water 2. have a cell wall (plants/bacteria) to resist expansion (balloons) 3. have a contractile vacuole- type of active transport which moves water out Active Transport- processes that require energy and generally move materials against a concentration gradient 1 Molecular Pumps- use energy to pull molecules across a membrane Ex: Contractile Vacuole Ex: Sodium Potassium 2 Endocytosis- bringing large materials into the cell by folding the cell membrane A Pinocytosis- taking in large amounts of liquid B Phagocytosis- taking in large amounts of solids 3 Exocytosis- removing large amounts of material from the cell Cell Specialization • all cells have a specialized function within an organism Specialized CellsPancreas- contain large amounts of organelles involved with protein synthesis (ER, RIbosomes, Golgi) make enzymes that go to your stomach for digestion Lungs- lined with cells that have cilia- hair-like projection that helps clean the air • also can secrete mucus which can be coughed up Red Blood Cells- specialized for oxygen transport White Blood Cells- fight against disease (lysosmes) Levels of Organization in Multicellular organisms • Cells • Tissues • Organs • Organ System • Organism Tissues- cells are organized into tissues and they perform a particular function 4 tissue types 1 Muscle- contains muscle & nerve cells 2 Epithelial- linings for body cavities, ducts, tubes- single layer (skin) 3 Nerve- many different types of nerve cells (brain, spinal cord) 4 Connective Tissue- bone, blood, cartilage, tendons, ligaments Organs- groups of tissue working together to perform a special function • each muscle is an organ • muscle- contains muscle, nerve and connective tissue • all needed to make the muscle function properly Organ Systems- groups of organs working together to perform specialized functions • 10 organ systems in the human body • can you name them? Division of labor- everything has a job, they all work together for proper functioning, if something isn’t doing its job the structure won’t work as a whole. Improper functioning Organism- Made up of organ systems Chromosome Structure Chromatids- identical forms across from each other Centromere- central structure that joins the chromatids Growth Factor and the Cell Cycle • most cells don’t divide unless they are signaled to do so Cell-Cycle Control System- set of proteins in the cell that both trigger and coordinate major events in the cell cycle • the control system sends signals at 2 critical points • G1 checkpoint- enter the S phase • M checkpoint - enter the M phase • Nerve and Muscle cells are permanently stopped at the G1 checkpoint (no growth factor) Cell Cycle includes the following: Interphase, G1, S, G2, Mitosis G2- growth needed for cell division Gap 1 cell growth and development Interphase- includes G1, G2, and S phases S- DNA synthesis (replication) The Cell Cycle- follows the life of the cell • includes: cell growth, preparation for division, cytokinesis • all cells move through it at different rates • one turn covers birth to division/death • CANCER- uncontrolled cell growth Cell Cycle Animation http://www.cancerquest.org/index.cfm?page=58 Mitosis- cellular division (nuclear) Cytokinesis- splitting of cell into 2 daughter cells Phases of Mitosis Prophase- longest phase • cells spend 50 to 60% of time here • chromosomes start to appear • centrioles separate and move to opposite sides of the nucleus • spindle fiber forms • chromosomes attach to the spindle • nucleolus disappears and nucleus breaks apart Prophase Animation http://www.phschool.com/science/biology_place/biocoach/mitosisisg/prophase.html Plant Prophase Animal Prophase Metaphase • shortest phase • chromosomes line up on the equator • centromeres attach to the spindles Metaphase Animation http://www.phschool.com/science/biology_place/biocoach/mitosisisg/meta.html Anaphase • centromeres split • sister chromatids split and move towards the poles • cytokinesis starts here- in late anaphase (the cell starts to split) Anaphase Animation http://www.phschool.com/science/biology_place/biocoach/mitosisisg/anaphase.html Telophase • final phase • chromosomes began to uncoil • nucleus begins to reform around chromatin • spindle breaks up • nucleolus becomes visible in both cells • cytokinesis continues, plants do not go through cytokinesis they form a CELL PLATE • mitosis is complete, cytokinesis is not Telophase animation http://www.phschool.com/science/biology_place/biocoach/mitosisisg/telo.html Mitosis Summary http://www.sumanasinc.com/webcontent/animations/content/mitosis.html Interactive http://www.cellsalive.com/mitosis.htm