UNIT+2+-+CELLS

By Aryn Cooper, Eshani Bhatt, and Abby Schmid When you see something through your bare eyes, it is almost like that is the only thing there. Take a flower petal for example. You might think that that is the only thing that is there, but there is so much more just to that little petal. The petal, like every other living thing, is made up of millions and millions of microscopic cells. A cell is the smallest structural and functional unit of an organism. In this unit, you will learn about the cell's organelles, cell transport, and cell mitosis. Cells play such an important role in a living organisms life, purely because if cells did not exist, then neither would we!
 * Unit Two: Cells **

-cell organelles -cell transport -cell mitosis
 * UNIT OBJECTIVES **

__ Terms to Know: __


 * __ 7-1: Life is Cellular __**
 * cell: ** smallest functional and structural part of a living thing
 * cell theory: ** states that all living things are composed of cells, cells are the basic units of structure and function in living things, and new cells are produced from existing cells.
 * Nucleus ** : a large membrane enclosed structure that contains the cells genetic material in the form of DNA. **plant cell>**
 * Eukaryotes ** : cells that contain nuclei
 * Prokaryotes ** : cells that do not contain nuclei


 * __ 7-2: Cell Structure __**
 * organelles: ** “little organs” within a cell
 * cytoplasm ** : portion of the cell outside of the nucleus
 * nuclear envelope ** : what the nucleus is surrounded by
 * chromatin: ** the granular material in the DNA that contains DNA that is bound to protein.
 * Chromosomes: ** what results when the chromatin condenses, inside is DNA that is bound to protein
 * Nucleolus ** : the small dense region of the nucleus where the assembly of ribosome begins.
 * Ribosome ** : where proteins are assembled.
 * Endoplasmic reticulum ** : the site where lipid components of the cell membrane are assembled, along with proteins and other materials that are exported from the cell.
 * Golgi apparatus: ** the function of this is to sort, modify, and package proteins and other materials from the endoplasmic reticulum for storage in the cell or secretion outside the cell.
 * Vacuoles ** : sac-like structures that store materials such as water, salts, proteins, and carbohydrates.
 * Mitochondria: ** organelles that convert the chemical energy stored in food compounds that are more convenient for the cell to use.
 * Chloroplasts ** : capture energy from sunlight and convert it into chemical energy in a process call photosynthesis.
 * Cytoskeleton ** : a network of protein filaments that helps the cell to maintain its shape. Also involved in cell movement.
 * Centrioles: ** located near the nucleus and help to organize cell division


 * __ 7-3: Cell Boundaries __**
 * cell membrane ** : thin flexible barrier that cell is surrounded by
 * cell wall ** : supporting later around the membrane
 * lipid bilayer ** : the composition of cell membranes is the lipid bilayer, and double layered sheet
 * concentration: ** mass of the solute in a given volume of solution, or mass/volume
 * diffusion: ** when particles move from an area where they are more concentrated to an area when they are less concentrated
 * equilibrium ** : when the concentration of the solute is the same throughout the system
 * osmosis: ** the diffusion of water through a selectively permeable membrane
 * isotonic: ** when the solutions are of the same strength
 * hypertonic: ** when the solution is “above strength”
 * hypotonic: ** when the solution is “below strength”
 * facilitated ** diffusion: molecules that cannot diffuse across the cell membranes lipid bilayer on their on move through the protein channels instead.
 * Active transport: ** requires energy. The active transport of ions across a cell membrane is general carried out by transport proteins.
 * Phagocytosis: ** extensions of cytoplasm surround a particle and package it within a food molecule
 * Endocytosis ** : process of taking material into the cell by the means of pockets of the cell membrane. The pocket breaks loose from the outer potion of te ell membrane and forms a vacuole within the cytoplasm.
 * Pinocytosis ** : where many cells take up liquid from the surrounding environment. Tiny pickets form along the cell membrane, fill with liquid, and punch off to form vacuoles from within the cell.
 * Exocytosis ** : the membrane of the vacuole surrounding the material fuses with the cell membrane, forcing the contents out of the cell. The removal of water by means of a contactile vacuole is one example of this type of active transport.