What is the difference between a prezygotic reproductive barrier and a postzygotic reproductive barrier? Provide an example of each
What will be an ideal response?
Prezygotic reproductive barriers prevent members of different species from mating in the first place or keep fertilization from occurring if they do mate. (A zygote is a fertilized egg, so prezygotic means before fertilization.). There are many types of prezygotic barriers—organisms may differ in when they breed, where they breed, or in the details of their courtship rituals. Their sex organs may not fit together properly, preventing successful sperm transfer, or other factors may prevent fertilization even if sperm is transferred. Postzygotic reproductive barriers act after fertilization has taken place. Postzygotic barriers occur when mating produces hybrids that either don't survive or are sterile—unable to breed themselves. The mule, the offspring of a horse and a donkey, is sterile and cannot reproduce. Likewise, a liger, the product of the mating of a lion and a tiger, is sterile.
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Cyclone
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At which location represented by the four positions on the map would you expect to hear the following 12-hour forecast: "Partly cloudy and continued warm through this afternoon and evening"?
A. position 1 B. position 2 C. position 3 D. position 4
The aurora that is visible in the southern hemisphere is the
For every integer increase of magnitude on the Richter Scale, ____________________ times more energy is released by the earthquake
Fill in the blank(s) with correct word
Which of the following is an example of the nonconsumptive use of water?
A) River navigation B) Hydroelectric power production C) Municipal treatment of wastewater D) Water consumption by humans and livestock