Download Cell Basics

Characteristics of Life
Carbon based
Water
Respiration
Stimulus
Energy source
Reproduction
Adaptation
Organization of multi-celled living things
Cells  tissues organs  system  organism
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Single celled organisms
Can live alone or in colonies
6 Kingdoms
 Animal
 Plant
 Fungi
 Bacteria – prokaryotes (simple celled)
 Moneran – eukaryotes (complex celled)
 Archea – extremophiles
Microscope 101
Robert Hooke – 1665
 3 lens in gold leather case
 poor quality (compared to a cheap microscope today)
 looked at cork, saw plant cells
Anton van Leewenhoek – 1700
 Improved accuracy and quality of lens
 Ground lenses himself
 First to name bacteria (animacuoles)
 Saw red blood cells
Compound Microscope
 Use either natural light or lamp
 Magnify power determined by multiplying of eye pieced and objective lens
 Eye piece (10) * Objective lens (30) = 300 magnifying power over
eyesight
Scanning Electron Microscope – 1970’s
 Beam electrons over the surface
 3D picture of surface
 Bt only get the surface
 60,000 magnification
Scanning Tunneling Microscope – 1980’s
 Beam electrons
 See atoms at objects surface
 Get a 3D image, still just a surface image
 100 million magnification
Transmission Election Microscope – 1990’s
 Beam electrons through specimen, denser portions allow fewer electrons
through, give a darker image to the denser sections
 Get a 2D image (a cellular x-ray)
 100,000’s times
New electron microscopes give greater detail, but do destroy the sample
Cell Theory / Cell History
William of Ockham - 1347
English Franciscan monk and philosopher
Ockham’s Razor
Plurality
should not be assumed without necessity
In otherwords, keep it simple
Robert Hooke – 1665
 Used very simple microscope, poor quality, little detail
 Only saw cell walls
 Saw simple box structures, called them cells
o (pg 176. in text for picture of what Hooke saw)
Francesco Redi – 1668
 Before Redi people believed in spontaneous generation
o Living things could come from dead/non-living things
 Ex. maggots born from rotten meat
 Redi proved that living things can only come from other living
things
 Put out three jars with meat in them
o One open top, one with a cork, one with cheese cloth (allowed air
to get to meat, but not the flies)
o Noticed flies hanging around
o Meat went rotten in all jars
o Only maggots formed on the open jars
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At time most educated people still did not understand disease or
that microbes came from other living microbes
* Many people still believed in spontaneous generation for microbes
* Something in the broth would make it go bad, they didn't think
that microbes did it
Anton van Leeuwenhoek - 1700
 Improved lens for microscopes
 Expanded knowledge of microbes
 Looked at pond water (saw microbes), blood (saw red blood cells), cheek
cells
Lazzarro Spallanzani - 1768
Showed that microbes are in the air and they could be killed by boiling
Boiled two flasks, sealed one and left the other opened
Sealed = clear
Opened = cloudy
Matthias Schleiden (1830’s)
 Observed plants
 All plants made up of cells
Theodore Schwann (1830’s)
 Observed animals
 All animals made up of cells
Louis Pasteur (1850’s)
 Proved all living things come from living things
 Also helped to prove that microbes caused disease & ruined food
 Found out that if heated liquids like (milk, apple cider, and wine) that the
flavor didn’t change, but that the microbes that ruined the food were dead
(pasteurization)
 Used flasks with curved ends to show that microbes ruined food, microbes
were every where, and that only came from other microbes
o Curved flasks were open to the air
o Boiled to kill microbes
o Microbes trapped in curve
o Took some flasks and ran both into curve
o Later those tipped flasks had microbes
o There are still open flasks that are free of microbes 150+ years
later
Robert Koch - 1880’s
Very methodical
Improved culturing techniques
Proved how disease was transmitted
Anthrax
TB
Tyhpus
Cell Theory
1. All organisms are composed from cells (One or more)
2. Cells are the basic unit of organization of organisms
3. All cells come from pre-existing cells
Types of Cells
Prokaryotes – Simple Cells
 Bacteria (Monerans)
 Lack internal membrane bound structures (organelles)
 Has no nuclear membrane
Eukaryotes – Complex cells
 Found in multicellular organisms (plants, animals, fungi)
 Protists (algae, yeast, paramecium, etc)
 Contain membrane bound structures (organelles)
 Has a nuclear membrane
Archea – Extremophiles
 Extreme loving single celled organisms
 Sort of a mix between prokaryotes and eukaryotes
 So different from both that are put into own category (own kingdom!)
Animal Cell Notes
Important chemicals needed for the Cell to Survive
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Lipids = fats
Carbohydrates = starch/stored energy
Glucose = sugar
Proteins = energy source, enzyme (starts reactions)
Organelles (“cellular organs”)
1. Membrane
2. Solid (mostly)
3. Microtubular (structure)
Inclusions
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Extra stuff in the cell
o Storage substances (ex. lipid droplets)
o Waste materials
o Products of the cell
o Pigment granules
o Foreign materials (ex. viruses)
Major Organelles
Cytoplasm – Goo stuff floats around in
 Fluid to jelly-like material that fills the cell
 Within the cell membrane
 EXCLUDING the nucleus
 Dissolved in the cytoplasm are simple sugars (ex. glucose), amino acids,
O2, CO2, ions, and large carbohydrates
 Suspended in cytoplasm: inclusions & organelles
Nucleus – Brain of the Cell
 Usually found in central part of cell
 Contains Chromatin
o DNA (genetic material) and proteins
o Genes (hereditary units) of the cell
Nuclear Membrane – Protects Nucleus
 Double membrane around nucleus
 Has pores in it, allows materials to pass in and out of nucleus
Nucleolus – Ribosome Maker
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Found within Nucleus
Makes ribosomes
Centrioles
 Present ONLY during cell division
 Microtubules that act
Endoplasmic Reticulum (ER) – Structure/Surface Provider
 Consists of highly folded sheets of membrane suspended
 Folded to form loose sheets or tubes
 Provides some physical support for cell
 Folds create inner compartments (cisternae) which are used to store some
of the produces synthesized by the cell
 Two types:
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Rough ER
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Has ribosomes on outer surface (hence “rough” ER)
Provides stable place where ribosomes can attach and make
proteins
Smooth ER
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Outer surface provides a tremendous amount of surface
area for synthesis (creating) of lipids and carbohydrates
Ribosome – Protein Producer
 Solid spherical particles of RNA (single strand of genetic info) and protein
 Frequently found on outer surface of ER
 Some are free floating
 Provides location for protein synthesis, ESSENTIAL for this purpose
 Ribosomes stabilize some of the molecules requires for protein synthesis
 Contain some of the enzymes needed for cellular respiration and electron
transport
Lysosomes - Garbage Men of Cell
 Sacs made of a single membrane (balloon-like)
 Contain hydrolytic enzymes that can break down large molecules into
smaller ones
 Enzymes destroy foreign material picked up by cell
 Also destroys worn out or injured cells (helps the cell “self destruct”)
Vacuoles – Storage Containers
 Sacs made up of a single membrane
 Store things in the cell
o Food and enzymes (for later use)
o Waste products made by cell
Golgi Apparatus (Golgi Complex) – Cells Mailman
 Stacks of discs (like pancakes)
 Always found close to ER and cell membrane
 Provide temporary storage to newly synthesized materials
 Vesicles – small sacs at the end of the Golgi stacks
o Contain a single membrane
o Can modify proteins into packages ready to be sent where they are
needed
 Modifies and sends proteins where they need to be
o Synthesis begins in ER  moves to golgi apparatus moves to
buds sent out of cell
Mitochondria – Energy Releaser
 Hollow structures, oval or rod shaped, double layer of membrane
 Inner membrane has intricate folds that project into a hollow cavity
o Provides more surface area
 Site of cellular respiration & electron transport
 Release large amounts of energy
o Can be released for immediate use or stored as ATP (high energy
compound)
 ATP = adenosine triphosphate
Cellular Respiration (How the cell breathes & eats)
 Break down nutrients to CO2 and water
 Allows cell to take in different gases and release waste gases
 Major energy activity (How cells get some of their energy)
 C6H12O6 +6O2  6H20 + energy
(glucose)
Electron Transport Chain
 Uses part of the energy released in cellular respiration to form ATP (high energy
compounds)
 Use a bit of energy to make “super battery cells” used in almost all cellular functions
Cytoskeleton
 Network that provides structure and strength to cell
 Give it rigidity and provide for cell movement
o Microfilaments – solid rods/fibers that provide structure
o Microtubules – hollow tubes that provide structure, allow stuff to
flow through tube
Cilia and Flagella
 How single-celled organisms move
 Thread-like projections out of cell (microtubules filled with cytoplasm)
 Basically the same thing, only difference is the amount
o Cilia - Lots of little threads, wave-like motion
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Flagella - One single large thread, whip-like motion
Plant Cell Notes
Contain all of the same organelles as animals cells with a few
differences
NO CENTRIOLES!
Cell Wall
 Has pores
 Provides structure and rigidity to plant cells
 Made up of cellulose
Plastids
 Often contain other pigments the cell uses for energy production
 Used to store energy (like a vacuole)
 Some contain starch or lipids
 These other plastids are what we see when the leaves change color
Chloroplasts
 Capture light and produce food
 Where photosynthesis takes place
 Chlorophyll
o Actual pigment that captures light energy
o Green color