What are alveoli? A. Part of a red blood cell
B. Air sacs used during respiration
C. Tubes that connect the heart to the lungs
D. Carbon dioxide molecules

Which process must a cell undergo top identical cells at the end of cell division

If someone could do the first couple, just so i can see how it's done that would be great! 20 points. complete a dichotomous key for the 10 leaves on the common leaves sheet. the chart provided here allows for 11 pairs of statements. depending on how you build your dichotomous key, you may or may not need all of them, or you may need to add some.

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