Cells divide at different rates. The fastest bacteria can divide every 20 minutes. No wonder you can feel sick with food poisoning within hours of eating undercooked food! On the other hand, some nerve cells in your body do not divide much at all. The nerve cells in a 100-year old person could be close to 100 years old! Read the examples of cell division below. Place a check mark next to the ones that represent MEIOSIS. No partial credit. You must select ALL the examples that relate to meiosis. * 20 points
A plant produces pollen cells with half the chromosomes of the parent cells.
A bacterium divides to make two identical daughter cells.
A skin cell divides rapidly to replace tissue damaged by a scrape.
A cell duplicates its genetic material once and then divides twice to make 4 daughter cells.

Match the descriptions / definitions with the term they best describe 1. three dimensional relationship of the different polypeptide chains in a multisubunit protein or protein complex 2. common folding pattern in proteins in which a linear sequence of amino acids folds into a right-handed coil stabilized by internal hydrogen-bonding between polypeptide backbone atoms. 3. the amino acid sequence of a protein 4. a region on the surface of a protein that can interact with another molecule through noncovalent bonding. 5. three-dimensional arrangement of alpha-helices and beta-sheets within a single polypeptide, typically stabilized by a variety of noncovalent bonds, including ionic and hydrogen bonds, and nonpolar interactions / hydrophobic force. 6. the chain of repeating carbon and nitrogen atoms, linked by peptide bonds, in a protein. 7. common structural motif in proteins in which different sections of the polypeptide chain run alongside each other and are joined together by hydrogen bonding between atoms of the polypeptide backbone. 8. portion of a polypeptide chain that has a discrete tertiary structure of its own and can often fold independently of the rest of the chain 9. regular local folding patterns in a protein, including alpha-helix and beta-sheet a. primary structure b. beta-sheet c. protein d. coiled-coil e. polypeptide backbone f. secondary structure g. side chain h. tertiary structure i. binding site j. alpha-helix k. quaternary structure l. protein domain

Which best describes how the common cold spreads in the human body? a bacteria burst out of normal cells killing them b viruses replicate inside respiratory cells c bacteria inject dna into normal cells d viruses insert dna into bacteria

Why does bubbling occur when vinegar mixed with baking soda