Biology Review 1 Cell The smallest organization 2 What are the 3 parts of the cell theory cells are the smallest unit of life all living organisms are made up of cells all cells come from preexisting cells 3 Structures of prokaryotic cells what are they and what do they do Plasma membrane controls what gets in and out of the cell Cytoplasm do not contain organelles but help support the cell Chromosome dna material Nucleoid has all the genes needed for survival and growth sex pilli helps divide it Ribosomes build proteins by translating sent from DNA Cell wall acts as cytoskeleton Flagella helps move the cell 4 Structures of Eukaryotic Plasma membrane Allows stuff to pass through cell signaling cell adhesion Cytoplasm contains organelles Highway of the cell Nucleus double bound Location of the genome gene regulation organization and protection of the chromosomes via the nuclear matrix Ribosomes is the site of polypeptide synthesis RER Site of protein sorting and secretion Golgi apparatus Site of modification sorting of lipids and proteins SER Site of detoxification and lipid synthesis Peroxisomes Site where hydrogen peroxide and other harmful molecules are broken down Lysosomes double membranes site where macromolecules are degraded Mitochondria double membrane site of ATP Semiautonomous Vacuoles provides storage Chloroplast photosynthesis Semiautonomous Cytoskeleton protein filaments that provide shape and aid in movement Cell wall only in plant cell Provides structure Flagella cilia cilia fused microtubules together whereas flagella moves the cell 5 What is the endomembrane system comprised of and what does it achieve functions protein synthesis modification sorting transport Golgi RER SER Nuclear envelope lysosomes vacuoles peroxisomes plasma membrane 6 How is the plasma membrane selectively permeable With positive and negative charges they have to be pumped with energy and some molecules are too big to move through the pores in the membrane 7 Are saturated fats solid or liquid at room temp solid 8 What is cholesterols role in the plasma membrane Helps maintain the integrity of the cell and helps firmness but still helps maintain fluidity It also helps secure important proteins in the membrane 9 General characteristics of passive transport diffusion move from high to low concentration facilitated diffusion o passive diffusion transport of a substance across membrane High to low No energy needed o Active transport moves substance from low to high Against concentration gradient requires atp 10 General characteristics of active transport small molecules o channels cell membrane Gated channels o transporters bind to solutes in a hydrophilic pocket and undergo a conformational change that switches the exposure of the pocket from one side of the membrane to the other Uniporters bind a single ion or molecule and transport across the membrane Symporter contransporters bind 2 or more ions or molecules and transport in the same direction Antiporters bind two or more ion or molecules and transport in opposite directions o pumps potassium protein pump and etc large molecules endocytosis secreted into cell and then lysosome breaks it down Exocytosis leaves cell and released in extracellular region 11 General features of cell communication why do cells need to communicate with each other Coordinate function apoptosis so they know when to divide 12 Cellular receptors and their activation describe 3 major types of cell surface receptors and give ex of each o Enzyme linked receptor tyrosine kinases o G protein coupled receptors common in animals Can bind to GTP o Ligand gated ion gated channels 13 Signal transduction and the cellular response outline the basic mechanism of different types of signal transduction pathways What is the significance of kinase cascades protein kinases phosphorylates and activates another kinase then activates another amplifies signals external signals can lead to changes in gene expression multiple steps leading to kinase activations can result in cells having different response depending on the presence of absence of target proteins multiple steps in a activation mean that abnormal stimulation of a cell response such as growth can occur with mutations in more that one gene Relate the function of second messengers to signal transduction pathways second messengers relay info from the receptor ligand complex They can amplify the signal 14 hormonal signaling in multicellular organisms