THE CELL _____________________ - is the scientist who 1st coined the term “cell” – in the 1660’s he observed ________ from a tree stem (they reminded him of the rooms monks lived in) Schleiden looked at ___________ & Schwann looked at _____________.  They both observed that ________________________________________________________.  Along with Virchow they formulated the __________________________.  It has 3 components. 1. ________________________________________________________________________________ 2.________________________________________________________________________________ 3.________________________________________________________________________________ Cells come in a great variety of shapes & sizes.  The smallest cells are ___________ & the largest cells are _________________________________.  The size & shape of the nerve cell are related to its ___________.  Sketch of a skin cell:                                                      Sketch of a nerve cell: The surface area of the cell does not increase at the same rate as the __________________.  Because of this cells typically stay small & will divide rather than getting larger. Differences in Cells 1.  ______________________ - have no true nucleus – DNA is not arranged into chromosomes – ex. = bacteria –  they have no __________________________________. 2.  ______________________ - have a nucleus - & cellular organelles. PARTS OF THE CELL 1.  ___________________ - control center of the cell – controls most of the activities of the cell ; also transmits hereditary information & contains DNA.  The nucleus holds ______________(threadlike) that are     seen only when the cell is dividing & ______________________(granular) when the cell isn’t dividing. 2.  ___________________ - these are found in the nucleus – where the assembly of ribosomes begins 3.  ___________________ - double membrane - this surrounds the nucleus & acts as a boundary between the nucleus & the cytoplasm – it contains pores that allow substances to pass 4.  ___________________ - this acts as the outer boundary of the cell & contains phospholipids & proteins - it is very important because it regulates what enters & leaves the cell 5.  __________________ - this is found in plants, algae, fungi, & bacteria- it protects & supports the cell – it lies outside of the cell membrane & allows water & gases to pass through – plant cell walls are made of ____________ 6.  __________________ - is the jellylike layer of the cell – it contains the ___________________ & moves      materials throughout the cell in a process called cytoplasmic streaming 7.  __________________ - this is a series of canals or channels that winds through the cytoplasm – it acts as the cell’s internal transport & connects with the nuclear envelope; there are 2 types – (1) ___________________-  this builds lipids for the plasma membrane, (2) ________________________ - has ribosomes attached to it 8.  _________________ - the sites of protein synthesis; 2 types (1) _____________ - makes protein to be used  in the cell, (2) ____________________ - make protein to be transported out of the cell 9.  __________________ - these pinch off from the ER – they are stacks of membranes that look like tiny flattened balloons – they are areas for storage & packaging of chemicals – enzymes in this apparatus attach carbohydrates & lipids to proteins 10. ___________________ - the cell’s powerhouse – they produce the energy for the cell – they have many folds on the inside called cristae that increase surface area for more energy 11.  __________________ - are found only in plants – some store food, others have pigments – 3 types:         (1) __________________ - colorless – store starches in roots & stems         (2) _________________ - they are orange & yellow – beta carotene         (3) __________________ - these are green & the sites for photosynthesis 12.  __________________ - bubblelike storage structures that store water, liquids, wastes, & foods – these hold plants erect & firm 13.  __________________ - these are membrane-bound organelles that are formed in Golgi bodies – they are        loaded with enzymes that digest large particles found in the cell – also break down old organelles 14.  __________________ - hollow cylinders of protein that support & shape the cell – found in the cytoskeleton, spindle fibers, centrioles, basal bodies, cilia, & flagella 15.  __________________ - appear during cell division & move chromosomes through the cytoplasm 16.  __________________ - small dark bodies located outside the nucleus – they are active during cell division 17.  __________________ - short, threadlike structures used for movement – they are numerous & hairlike 18.  __________________ - long, whiplike structures used for movement – usually only 1 per cell 19.  __________________ - network of protein filaments that helps the cell to maintain its shape – also involved in cell movement  - these are made of: a) ___________________ - hollow tubes of protein – maintain cell shape & serve as “tracks” along which organelles are moved (used to make cilia & flagella) b) ___________________ - long, thin fibers that function in the movement & support of the cell – tough, flexible framework that supports the cell