[ foh-tuh-peer-ee-uh-diz-uh m ]
/ ˌfoʊ təˈpɪər i əˌdɪz əm /
the response, as affecting growth or reproduction, of an organism to the length of exposure to light in a 24-hour period.
TAKE THIS QUIZ TO SEE WHAT YOU KNOW ABOUT HIGH SCHOOL PUNCTUATION!
Commas mark divisions in sentences. Periods end declarative sentences. Apostrophes show possession. Easy, right? Well, punctuation can get pretty tricky—fast. Think you got what it takes to be a punctuation expert? Take our quiz to prove it!
Question 1 of 10
Which of the options below is the best punctuation for the sentence? It__s your turn to pick the movie __ but your sister gets to pick the board game we _ re going to play.
Its your turn to pick the movie but your sister gets to pick the board game we’re going to play.
It’s your turn to pick the movie but your sister gets to pick the board game were going to play.
It’s your turn to pick the movie, but your sister gets to pick the board game we’re going to play.TAKE THE QUIZ TO FIND OUT
Also called pho·to·pe·ri·o·dic·i·ty [foh-toh-peer-ee-uh-dis-i-tee] /ˌfoʊ toʊˌpɪər i əˈdɪs ɪ ti/.
Words nearby photoperiodism
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2020
British Dictionary definitions for photoperiodicity
/ (ˌfəʊtəʊˈpɪərɪəˌdɪzəm) /
the response of plants and animals by behaviour, growth, etc, to photoperiods
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Medical definitions for photoperiodicity
[ fō′tō-pîr′ē-ə-dĭz′əm ]
The response of an organism to changes in its photoperiod, especially as indicated by vital processes.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
Scientific definitions for photoperiodicity
[ fō′tō-pîr′ē-ə-dĭz′əm ]
The response of an organism to changes in its photoperiod, especially as indicated by vital processes. For example, many plants exhibit photoperiodism by flowering only after being exposed to a set amount of daylight, as by requiring either a long or short day to flower. Plant growth, seed germination, and fruiting are also affected by day length. Photoperiodic responses in plants are regulated by special pigments known as phytochromes. In animals, migration, mating, amount of sleep, and other behaviors are also photoperiodic. In many animals, photoperiodism is regulated by the hormone melatonin.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.