CHAPTER 1   CELLS THE BUILDING BLOCKS OF LIFE

ORGANISM – a living thing

        

http://www.le.ac.uk/se/centres/sci/selfstudy/functions.jpg   http://www.jehmpublications.com/Art%20Gallery/Final%20organisms.jpg

6 CHARACTERISTICS OF LIVING THINGS 
a.      use energy – have a metabolism- the building up and breaking down of chemicals

www.fitnessforlife.ie/images/jogger.jpg                                             webanatomy.net/anatomy/muscle3_notes.htm

b.     grow and develop become larger and more complex

ocw.tufts.edu/.../humangrowthdevelopment.jpg                                                  www.butterflyhouse.com.au/images/Lifecycle.jpg

c.     respond to their surrounding
       stimulus – a change in an organism’s surroundings, it causes organism to react 
    www.georgiapainphysicians.com/downloads/m1_sl...
         response- a reaction or change in behavior a reaction to a stimulus www.mercola.com/.../Public/2005/August/pain.jpg

 

d.     reproduce- produce offspring that are similar to the parents   blog.rabbitnetwork.org/.../2006/05/Babies.JPG

e.     have the chemicals of life, carbohydrates, proteins, lipids and nucleic acids (genetic material)

f.     have cells
unicellular – single celled  paramecium

multicellular- many celled  as in humans

  
bone cells                                                                        nerve cells
cell pictures from www.uic.edu/classes/bios/bios100/labs/celllab.htm

SPONTANEOUS GENERATION- an UNTRUE THEORY stating that living things arise from nonliving sources FRANCESCO REDI  in the 1600’S DISPROVED THIS IDEA
 
   CONTROLLED EXPERIMENT- A scientist carries out two tests that are identical in every way except for one factor.

   MANIPULATED VARIABLE- the factor that the scientist changes

Redi proved life comes from life       flies comes from the eggs of flies

PASTEUR  a French chemist in 1800’s showed even microbes exhibit biogenesis.

BIOGENESIS life comes from life. He used two bottles with a curved neck.  He boiled the broth in the bottles and left them uncovered.  The broth remained clean in each bottle for over 1 year.  The microbes were settling in the dust in the curve of the neck of the bottles.  By tilting the bottles the broth mixed with the microbes in the neck of the curved flask  The microbes had food, reproduced and spoiled the broth.

Broth is boiled  Dust with microbes in neck	flask is tilted broth contacts microbes	microbes growing in broth Broth is spoiled within a week No contamination for 1 year

LIFE COMES FROM LIFE even if it is very small

ORIGIN OF LIFE Earth’s early atmosphere was made of nitrogen  N₂  water vapor  H₂O, carbon dioxide  CO₂ , And methane  CH4  

 Miller and Urey mixed gases with water vapor, added electrical current and with in a week the mixture darkened.  The small chemical units if joined could form protein which is one of the building blocks of life

 FIRST CELL  - is hypothesized that the small chemical units of life formed gradually over millions of year in the Earth’s water.  They joined to form large chemical building block and eventually became the first forerunners of cells

 Fossils are traces of ancient organisms that have been preserved in rock or other substances

4 THINGS ALL LIVING THINGS NEED 
         Living things need energy, water, living space and stable internal conditions


AUTOTROPHS – “auto” means self and “troph” means feeder.  They make their own food and use it as an energy source to carry out life functions.
     Plants use sunlight and carbon dioxide and water to make their own food http://nas.er.usgs.gov/taxgroup/plants/images/plant_logo.jpg


HETEROTROPHS – hetero means “other”   They have to eat autotrophs or other heterotrophs to obtain energy 

 

Water has the ability to dissolve more chemicals than any other substance on Earth.
 

All organisms need a place to live
  

HOMEOSTASIS – the maintenance of stable internal conditions despite changes in the surrounding.  An organisms must be able to keep the conditions inside their bodies constant.

 CHAPTER 1   SECTION 2   DISCOVERING CELLS

CELLS- are the basic units of structure and function in living things.

Microscope – is an instrument that makes small objects look larger 

Compound microscope – a light microscope that has more than  one lens 

ROBERT HOOKE- first to look at cells
            looked at a thin section of cork

his cell drawing of a cork

ANTON VAN LEEUWENHOEK – made his own lenses made first compound microscope drew pictures that we can still identify today.  

http://www.microbeworld.org/images/meetmicros/tools/tool_1_leuw-scope.jpg      http://www.euronet.nl/users/warnar/radardiertjeHBAKER.jpg

Schleiden –concluded all plants are made of cells

Schwann – concluded all living things are made up of cells

 

CELL THEORY         CHAPTER 1     SECTION 3
            1. ALL LIVING THINGS ARE COMPOSED OF CELLS
            2. CELLS ARE THE BASIC UNIT OF STRUCTURE AND FUNCTION IN LIVING THINGS
            3.ALL CELLS ARE PRODUCED FROM OTHER CELLS

MAGNIFICATION – is the ability to make things look larger than they are.  The lens or lenses in a light microscope magnify an object by bending the light that passes through them.

Convex lens- the center of the lens is thicker than the edges.
Resolution – the ability to clearly distinguish the individual parts of an object it is the sharpness of an image
 Electron microscopes – a beam of electrons instead of light is used to examine a specimen
 

 CHAPTER 1     SECTION 3            INSIDE CELLS
a great place to learn about cells http://www.cellsalive.com/

ORGANELLES – small structures inside cells that carry out specific functions within the cell.

 CELL WALL – is a rigid layer of nonliving material that surrounds the cells of plants and some other organisms.
                It protects and supports the cell
                It adds strength
                 Material like water and oxygen can pass through easily
                It is made from a tough flexible material called cellulose – fiber   we can't digest this but it helps keep you regular.
 
CELL MEMBRANE – forms the outside boundary that separates the cell from its environment.  HAS TINY PORES THAT LET SUBSTANCE INTO AND OUT OF THE CELL  food water oxygen in and harmful waste product can leave.  Acts like a window screen.

NUCLEUS- acts as the cell’s control center directing all of the cell’s activities  “brains of the cell”  

NUCLEAR MEMBRANE- “gatekeeper”  protects the nucleus and allows materials to pass in and out of the nucleus through pores.

CHROMATIN – contains the genetic material.  (the instructions that direct the function of a cell)  becomes a chromosome

http://micro.magnet.fsu.edu/cells/nucleus/images/chromatinstructurefigure1.jpg

 NUCLEOLUS – is where ribosomes are made it is inside the nucleus

http://upload.wikimedia.org/wikipedia/commons/thumb/3/38/Diagram_human_cell_nucleus.svg/300px-Diagram_human_cell_nucleus.svg.png

CYTOPLASM – the area of the cell between the cell membrane and the nucleus.  It is a thick gel like fluid.

http://www.daylilies.org/ahs_dictionary/cytoplasm.gif

 MITOCHONDRIA – “POWERHOUSE” produce most of the energy the cell needs   they can reproduce by themselves the more mitochondria the more energy you have.

 ENDOPLASMIC RETICULUM – “transports” passage way carry proteins from one part of the cell to another                                www.ureacycle.com/images/cell.gif

 RIBOSOMES – “protein factory”  they make proteins and pass it to the endoplasmic reticulum.

 GOLGI BODIES – “mailroom”  they receive proteins, package them, distribute them to others parts of the cell and release materials to the outside of the cell.

 CHLOROPLAST – “solar panels” capture energy from the sunlight and use it to produce food for the cell

   

CENTRIOLES - help the animal cell to divide. 

VACUOLES – “storage tanks”  water filled sac in cytoplasm.
          Most plants have one large vacuole  some animal don’t have a vacuole others do.  Vacuoles can store food wastes salts and water

 LYSOSOMES – “clean up crew" contain chemical to break down large food particles into smaller ones and can break down old cell parts and release the substances to be used again.   Membrane around Lysosome keeps the harsh chemicals from escaping and breaking down the rest of the cell

http://www.sci.uidaho.edu/bionet/biol115/help/the_cell/animal_cell.htm
plant cell       great cell quiz

PROKARYOTES –organisms whose cells lack a nucleus

 BACTERIAL CELL does have a cell wall and cell membrane it does not contain a nucleus.
            Genetic material looks like a thick tangled strand
            Is found in the cytoplasm
            Contains ribosomes
            Does not have other organelles like plants or animal 

EUKARYOTES – Organisms whose cells contain a nucleus and many organelles.
 

 Specialized cells – found in many celled organism make up different body parts.
            the structure of each kind of cell is suited to the unique function it carries out with in the organism. 

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