A person exhales carbon dioxide and moisture. Which example of the characteristics of life is most similar?

A.
A gazelle runs away from a lioness.
B.
An algal cell has a defined boundary.
C.
A dog defecates when outdoors on a walk.
D.
A 12-year-old boy’s voice breaks.

How can you keep track of variables in a science experiment?

Which of the following sex and generation combinations directly produces the pollen tube of angiosperms? a) male gametophyteb) female gametophytec) male sporophyted) female sporophyte

How is ribosomal rna useful as a molecular clock? a. a large portion of the dna ring is not vital to structure or function, allowing it to accumulate neutral mutations. b. its rate of mutation increases over time as organisms continue to evolve and differentiate from each other. c. a slow mutation rate makes it useful for determining evolutionary relationships between ancient species. d. it is only found in select organisms, making it easier to compare relationships between species that have it.