Bellwork 116 Put phone up Week 115 119
Bellwork: 11/6 Put phone up Week 11/5 -11/9 1. Turn in cell packet 2. Grab a new unit book 3. Take out the cell video ? s
Objective • Finish the Cell Video • Unit III, pt I notes
Today: 1. The Cell Video 2. Choose groups 3. Unit III, pt I
This Week: • Monday: The Cell Video • Tuesday: Unit III, Pt. I Notes • Wednesday: Finish notes, organelle review, poster project • Thursday: Poster • Friday: Poster
Materials • Video ? s • Unit III Book
Homework • Bring in poster board • Due Thursday
Part 1: Cell Structure
Bacterium Plants
Discovery • Came with the invention of the microscope • Key Findings: • Leeuwenhoek (1665) • Using a self-made microscope; first person to see living cells • Robert Hook (1665) • Looking at cork – first to coin term “cell” • Robert (1831), Scheiden (1838), Schwann (1839) • Collectively showed that plants and animals composed of cells • Rudolph Virchow (1855) • Cells arise from existing cells – Spontaneous Generation • Got credit for Robert Remak’s work
Cell Theory • Three principles that all living things follow: 1. 2. 3. All living things are made up of cells Cells are the basic unit of function for all living things New cells arise from pre-existing cells
Exceptions • Viruses: non-cellular • Chloroplasts & mitochondria: not cells; yet, have their own genetic information & can replicate
Examination of Cells • Compound light microscope: • Uses a series of lenses to focus visible light rays • Visible light rays pass through the specimen • Creates a magnified image detected with human eye • Magnifies 1000 x
Examination of Cells • Transmission electron microscope: • Magnifies 100, 000 X • Used to examine the internal structure of cells-individual organelles (ex. Mitochondria)
Examination of Cells • Scanning electron microscope: • Creates a 3 -D image on a monitor • Used to examine surface topography of a specimen
Features of all Cells • Outer membrane: boundary separating inside from outside the cell • Cytoplasm: makes up the cell interior • Ribosomes: synthesizes proteins • DNA: provides instructions for… • Making proteins • Regulating cell activities • Reproduction
Two Cell Types • Eukaryotic Cell • Means “true nucleus” • Prokaryotic Cell • Means “before nucleus”
Prokaryotic Cells • Bacteria & Cyanobacteria • Considered the simplest cellular organism
Prokaryotic Cell Structure • Distinguishing characteristics: • Enclosed in an outer membrane • No internal membrane-bound organelles • Interior is one continuous compartment • No nucleus • DNA found in the nucleoid region • Most prokaryotes contain a cell wall • Different composition from plant cells • No internal support structure • No cytoskeleton • Support comes from cell wall
Eukaryotic Cells • Found in plants, animals & fungi • Divided into 3 regions: • Outer membrane • Nucleus • Cytoplasm • Occupies volume between nucleus & outer membrane
Eukaryotic Cell Structure • Distinguishing characteristics: • Interior compartmentalized • Membranous and non-membranous organelles • Each have specific functions within the cell • Nucleus • Membrane-bound organelle that houses the DNA • Cell walls limited to certain types • Plant cells, some fungi • Some protists (ex. Paramecium)
Think-Pair-Share • Use a Venn diagram to show Prokaryotic and Eukaryotic cells are alike and how they are different • Use at least 2 concepts in each compartment of the diagram • Be ready to share!!
Eukaryotic Cell Structure • Further classified into: • Plant cells • Animal cells
2 Types of Eukaryotic Cells • Animal Cell • Distinguishing Characteristics: • No cell wall • Lysosomes-digestive organelle; breaking down macromolecules and worn-out organelles • Centriole-involved in microtubule organization
2 Types of Eukaryotic Cells • Plant Cell • Distinguishing Characteristics: • Has cell wall – also found in fungi & some protists • Large central vacuole – involved in storing metabolites and water • Plastids – varied functions
Chloroplasts • Found in plants & algae • Site of photosynthesis • Converts sunlight to chemical energy used to synthesize sugars from CO 2 and water
Plastids • Chloroplasts are a specialized member of a family of organelles called plastids • Several specialized types • Leucoplast – colorless, synthesizes and stores starch • Found in roots and tuber • Chromoplast – stores pigments • Responsible for color in autumn leaves, fruits and some flowers
Central Vacuole • Involved in • Storage • Holds reserves of organic compounds • Stores byproducts that would be toxic to the cell • Stores pigments • Growth • Fills with water that pushes cytoplasm against cell wall • If cell wall has capability to loosen, cell wall will expand
Answer ? s in your Note Guide:
- Slides: 28