The Cell Structure Ag Biology

Cell Overview  CELLS-The common thing that makes up every living thing  Anton van Leeuwenhoek was the first person to use a microscope to study nature.  Robert Hooke was the first to look at plant tissues under the microscope.  Rudolf Virchow studied cell reproduction and declared that “Where a cell exists there must have been a preexisting cell…”

The Cell Theory States the Following:  All living things are composed of cells.  Cells are the basic units of structure and function in living things.  New cells are produced from existing cells.

Basic Cell Structures  Micrometer (1,000 times smaller than a millimeter)  The tiniest bacteria cells are only 0.2 micrometers.  Typical cells range from 5-50 micrometers.

Prokaryotic Cells  Prokaryotes – are small and simple  have cell membranes and cytoplasm  no nuclei  all bacteria are prokaryotes  they still grow, reproduce, and respond to stimuli

Eukaryotic Cell  they contain nuclei, and dozens of other structures called organelles  but most are a part of a multicellular system

PARTS OF A CELL-don’t write  Structures within a cell are called ORGANELLES  Have specific functions within the cell and structures  Carry out essential cell processes

Nucleus  controls cell processes and contains DNA.  Chromatin – the visible material within the nucleus (form chromosomes)  Nucleolus – within the nucleus, where ribosomes are made  Nuclear Membrane –surrounds the nucleus and allows items to flow in/out

Cytoskeleton  network of protein filaments that helps the cell maintain its shape.  Involved in the movement of the cell.  Microtubules & Microfilaments

Ribosomes  Ribosomes are made of proteins and RNA (RiboNucleic Acid).  Produced in the nucleolus  Some free floating, some attached to endoplasmic reticulum

Endoplasmic Reticulum  Transport proteins out of the cell  Site of protein synthesis  The ‘rough ER’ has ribosomes on its surface, Smooth = no ribosomes

Golgi Apparatus  Proteins produced by the rough ER move into the Golgi Apparatus.  Packages proteins into vesicles that can be transported out or around the cell.

Lysosomes  “clean up crew”  Digest bacteria/viruses/worn out organelles

Centriole  Made of microtubules  Found in cytoplasm near nucleus  Aid in cell division

Vacuoles  Store water, salts, proteins, and carbs in saclike structures.  Plant cells usually have one large vacuole so the plant can support heavy structures.

Mitochondria  “energy generator” or “powerhouse”  release energy from stored foods to make compounds that the cell can use to power growth, development, and movement.

Cell Wall – only in plant cell  Not in animal cell.  made from fibers making a tough substance called cellulose.  provides protection and support for the cell.

Chloroplasts – plant cell only  Use energy from the sun to make energy rich food.  AKA photosynthesis.

Activity!  Fill out the worksheet on the parts of the cell and be thinking about how you could turn all of these cell parts into a self sustaining city.  You get to make a…  Cell City!