Etrog vs. Lemon

With the holidays just wrapping up, studying etrogs from a biological perspective seemed like a great way to kick off Science Explores aka Life Science. The etrog, more commonly known as the citron, belongs to the citrus family of flowering plants. Etrog trivia: The "pittom" is which part of the flower?1

Then we asked the question: Is an etrog simply an over-priced, funny-shaped lemon, or is there more going on?2 We made some external observations, noting their shape, color, volume, mass, and density. Then we opened them up and looked inside. Turns out, there are some interesting differences in the relative proportions of peel, fruit, and juice volume. We measured each fruit's pH, and then celebrated a job well-done to the tune of a tall glass of lemonade. Due to the lack of juice, the etrogade wasn't as successful.

More ETROG TRIVIA...
"Flavedo" and "albedo" are
a. the yellow and white parts of the rind
b. trapeze artists, as in "The Amazing Flavedo and Albedo"
c. great scrabble words, well "flavedo" anyway
(3)

Answers
1. The stigma, the part that receives pollen grains
2. There's more going on 
3. a.