1. Objectives: 4(A) Compare and contrast prokaryotic and eukaryotic cells. 4(B) Investigate and explain cellular processes, including homeostasis, energy conversions, transport of molecules, and synthesis of new molecules.

5.  The environment enclosed by the plasma membrane is a semifluid material called cytoplasm.  In prokaryotes, all the chemical processes of the cell take place directly in the cytoplasm.  In eukaryotes, these cell processes take place within organelles in the cytoplasm.

6.  The cytoskeleton is a supporting network of long, thin protein fibers that form a framework for the cell and provide an anchor for organelles.  Microtubules are long, hollow protein cylinders that form a rigid skeleton for the cell and assist in moving substances within the cell.  Microfilaments are thin protein threads that help give the cell shape and enable part or the entire cell to move.

8.  The nucleus  Contains most of the cell’s DNA, which stores information used to make proteins that determine a cell’s growth, function, and reproduction.  Surrounded by a double membrane called a nuclear envelope.

9.  Ribosomes  Organelles that manufacture proteins. ▪ Not membrane-bound like other organelles. ▪ Produced inside the nucleus in the nucleolus.

10.  Endoplasmic reticulum (ER)  A membrane system of folded sacs and interconnected channels that serves as the site for protein and lipid synthesis.  Two types: rough ER and smooth ER

11.  Golgi apparatus  A flattened stack of membranes that modifies, sorts, and packages proteins.  Proteins are packaged into sacs called vesicles, which can fuse to the plasma membrane and release the proteins to the environment.

12.  Lysosome  Are vesicles that contain substances that digest excess or worn-out organelles and food particles.  Also digest bacteria and viruses that invade the cell.

13.  Centrioles  Organelles made of microtubules that function during cell division.  Located in the cytoplasm.

14.  Mitochondria  Convert food particles into usable energy.  Have an outer membrane and a highly folded inner membrane that provides surface area for breaking the bonds in sugar molecules.

16.  Vacuoles  A membrane bound sac used for temporary storage  Store food, enzymes, or waste.  Found only in plant cells.

17.  Chloroplasts  Found in plant cells and some other eukaryotes.  Capture light and convert it into chemical energy during photosynthesis.  Contain multiple small disks called thylakoids, which contain the light capturing pigment chlorophyll.

18.  Cell Wall  Found in plant cells.  A thick rigid, mesh of fibers that surround the outside of the plasma membrane. ▪ Protects the cell ad gives it structure. ▪ Made from a carbohydrate called cellulose.

19.  Cilia and Flagella  Cilia are short, numerous projections that look like hair. ▪ Move in tandem like oars in a rowboat.  Flagella are longer and less numerous than cilia. ▪ Move with a whip-like motion.  Both are made of microtubules.

21.  Features plant cells have that animal cells generally do not:  Chloroplasts/chlorophyll  Vacuoles  Cell walls

22.  An understanding of different organelles allows for an understanding of cellular processes.  Example: Protein synthesis:  Begins in the nucleus with information contained in DNA.  RNA and ribosomes leave the nucleus and produce a protein on the ER.  Proteins produced in the ER are sent to the Golding apparatus for packaging.  Packaged proteins are delivered to other organelles where they serve a variety of functions.