Consider medium freshness.
a. why is it important that this medium be fresh?
b. which type of organism (obligate aerobe, obligate anaerobe, microaerophile, facultative anaerobe, aerotolerant anaerobe) would most likely be affected negatively by the use of old media?
c. which would most likely be affected positively by the use of old media?
d. which would be least affected by old media?

the diploid number of chromosomes is sometimes represented by the symbol 2n. for the fruit fly, the diploid number is 8, which can be written as 2n = 8, where n represents twice the number of chromosomes in a sperm or egg cell.

colors do exist. the color of the sky is actually violet; humans percieve the color of the sky as blue.

not necessarily. higher fitness requires the organism to be reproductive successful. for example, an organism at age 10 with 15 offspring is much more fit than an organism at age 15 with only 5 offspring.