Chapter 3 Learning Outcomes for Exam Two Basic Cell Structure and Diversity o Explain the concept of a cell and Cell theory -A cell is like a small, bustling town & all of its anatomical parts have special, unique roles in keeping the town smoothly functioning. Each cell has different specialties, & like towns these cells do ‘commerce’ (aka communication) with one another to optimal efficiency. The vitality of these cells is integral to the survival of their ‘sovereign nation’ (the organism which they belong to). - Cell Theory: states that cells are the basic units of life. 1) All living things are made of one or more cells 2) The smallest organisms are single cells, & cells are the functional units for all multi- cellular organisms. 3) All cells come from pre-existing cells. o Understand the relationship between cell surface area and cell volume, placing this information in the context of cell efficiency and limits on cell size . -The size of a cell determines its function. -Exchange of material across membranes influences cell size and shape -As a spherical cell enlarges, its innermost parts get farther away from the plasma membrane -As the cell gets larger, diffusion, which is relatively slow, can take too long to supply important processes deep within the cell -Because its volume increases more rapidly than its surface area, a larger cell has a relatively smaller area of membrane for acquiring nutrients and eliminating waste products than a smaller cell -Nerve and muscle cells and microvilli overcome size restraints by elongating, thus keeping the ratio of surface area to volume relatively high. o Be able to list the major differences between prokaryotic and eukaryotic cells -Prokaryotic cells are much smaller, lack organelles & membrane bound nucleus. Found in domains of Archaea & Bacteria. -Eurkaryotic cells are larger, more complex, contain organelles & nucleus, & are found only in the Eukarya domain. Components of All Cells o Identify the structures (and their functions) common to all cells: Plasma Membrane, Cytoplasm, Chromosome (DNA), Ribosomes . - Plasma Membrane : encloses the cell and allows interactions between the cell and its environment. (This structure is composed of lipid, protein, and carbohydrate molecules, and regulates the passage of ions and molecules in and out of cells.) - Cytoplasm/cytosol : is made of the fluid and structures that lie inside the plasma membrane but outside of the nucleus. (The fluid portion of the cytoplasm (cytoplasmic fluid) contains water, salts, and organic molecules. Most of the cell’s metabolic activities occur in the cell cytoplasm.) - Chromosomes : carry genes. (DNA is the hereditary blueprint, while RNA is the copy of the blueprint that guides the construction of proteins.) - Ribosomes : make proteins.
Eukaryotic Cells o Describe the structure and function of the following eukaryotic cell structures : Nucleus - controls activities of cell; contains chromosomes (DNA, RNA) & nucleolus; filled with nucleoplasm Rough Endoplasmic Reticulum – is studded with ribosomes and produces proteins