Graphite is: a. harder than glass. b. the lead in the pencil you write with. c. the polymorph of galena. d. composed of carbon atoms, arranged as tetrahedrons, held together with strong covalent bonds. e.

What must happen before meiosis can begin? a. four gametes must be produced b. the four tetrads must be pulled apart c. dna doubles and produces sister chromatids d. the cell membrane pinches together

Which statements about the fluid mosaic structure of a membrane are correct? select the three correct statements.which statements about the fluid mosaic structure of a membrane are correct? select the three correct statements.the framework of a membrane is a bilayer of phospholipids with their hydrophilic heads facing the aqueous environment inside and outside of the cell and their hydrophobic tails clustered in the center.because membranes are fluid, membrane proteins and phospholipids can drift about in the membrane.the diverse proteins found in and attached to membranes perform many important functions.the kinky tails of some proteins keep the membrane fluid by preventing the component molecules from packing solidly together.membranes include a mosaic, or mix, of carbohydrates embedded in a phospholipid bilayer.

Jason adds the antibiotic penicillin to a bacterial culture. the bacteria develop genetic modifications in their genome, which gives them resistance to the antibiotic penicillin. what caused this genetic modification?