Part 1
Microscopes & Cells
Microscopes and Cells: History In 1663, __________ coined the term “cells” 10 years later, _________________ observed bacteria and protozoa In 1833, __________ observed and coined the term “nucleus” Robert Hooke Anton van Leeuwenhoek Robert Browne
Cell Theory: History In 1838 (and 1839) German scientists, ________________ & ________________ independently came up with the “Cell Theory” Matthias Schleiden Theodore Schwann Guten Tag, Dr. Shwann Guten Tag, Dr. Schleiden It appears we have come up with a very similar theory… What shall we call this theory?
Cell Theory 1.All living things are composed of one or more cells. 2.Cells are organisms' basic units of structure and function. 3.Cells form by free-cell formation, similar to the formation of crystals (spontaneous generation).
In 1855, German physician Rudolph Virchow discovered that… I do believe that all cells must come from pre- existing cells.
How big are cells? Eukaryotic cells include _______ & _______ cells. Most eukaryotic cells are between __ and ___ m. What is the limit of the light microscope? Why? What is used to see smaller objects? __________________ plantanimal Electron Microscopes 0.2 m
Electron Microscopy ___________ Electron Microscopes (TEM) emit light through a thin piece of heavy metal ion stained tissue ________ Electron Microscopes (SEM) reflect light off of a piece of heavy metal ion stained tissue Transmission Scanning
Prokaryotic Cells (cells without a nucleus) for ex. bacteria DNA (Nucleoid) Ribosomes Plasma Membrane FlagellumFlagella Cytoplasm TEM of a bacterium CiliumCilia
Differences and similarities between Prokaryotes and Eukaryotes Differences Prokaryotes lack: 1.True nucleus 2.Membrane bound organelles Prokaryotes are much smaller than eukaryotes (prokaryotes are ~1 – 10 m) Similarities Both have: 1.DNA 2.Cytoplasm 3.Ribosomes 4.Plasma Membrane
Part 2
Eukaryotic Cells (cells with a nucleus) Comparing and Contrasting Organelles in Eukaryotic Cells
The Plasma Membrane TEM of a red blood cell Hydrophilic Region Hydrophobic Region Phospholipid Proteins Carbohydrate side chains
The Plasma Membrane It is a semi-permeable barrier that allows for the passage of certain things based upon ______, _______, and _____________. What are the forms of transport across a cell membrane? H 2 O used by cell for Respiration size charges solubility in fat
Fingerlike-projections from the cell’s surface that increase the surface area. Microvilli Intermediate Filaments Microfilaments Plasma Membrane’s Microvilli
Cytoplasm The jelly-like fluid that holds all organelles within the cell
Nucleus and nucleolus Ribosomes are made here: DNA and proteins are found in the nucleus Openings in the nuclear membrane SEM of a freeze-fractured nuclear membrane TEM of nuclear pores nucleolus chromatin Nuclear pores
Ribosomes: Function in TEM of ribosomes Free ribosomes Attached ribosomes (on ER) protein synthesis (formation) Ribosome unit free ribosomes 1.Proteins made by free ribosomes stay in the cell attached ribosomes 2.Proteins made by attached ribosomes are shipped out of the cell or sent to the membrane
Endoplasmic Reticulum There are two types: 1. ER has ribosomes attached. Modifies & transports proteins 2. ER does not have ribosomes on it. Synthesizes Breaks down carbohydrates Detoxifies drugs & poisons Rough Smooth lipids
Golgi Apparatus ER products move here in It is the center of Warehousing, Sorting and Shipping of Proteins vesicles
Mitochondria takes place in this organelle. It is often called the “ “ of the cell. Cellular Respiration powerhouse
The Cytoskeleton A network of fibers that extend throughout the cytoplasm Three types: Microtubules Microfilaments Intermediate Filaments
Cytoskeleton: Functions 1.Provides shape and support 2.Moves the cell and organelles 3.Regulates biochemical activities in cell Organelle
Centrosome Microtubules grow out of this structure In animal cells, a pair of structures called (made of microtubules) help in cell division. centrioles centrosome
Cilia and Flagella Cellular projections that aide in movement Flagella are longer & move in a snake-like motion. Cilia are shorter, more numerous and move back & forth
Lysosomes Membrane-bound organelle that contains enzymes digestive Lysosome engulfing a peroxisome and a mitochondria
Chloroplasts An organelle that converts energy from the sun into chemical energy The process is called: Photosynthesis
Cell Wall Surrounding the, this feature does the following for plant cells: 1.Provides Support 2.Provides Protection cell membrane
Vesicles Membrane- bound organelles that transports materials from the ER to the golgi
Vacuoles Large, central organelle in plants Stores water and waste products In animals, it stores food and is small compared plant vacuoles Protists have a Contractile Vacuole