Hi there!
A prezygotic isolating mechanism is a mechanism that causes something to happen, not allowing the organisms to breed before fertilization. I'll explain each one for you.
A - That is postzygotic because the organisms were not stopped before fertilization. The result is a sterile organism.
B - Again, that is postzygotic because the organism was produced.
C - This is prezygotic! The sperm dying shows that something is in action to prevent fertilization, meaning that it cannot happen.
D - Fertilization was successful, so it is postzygotic.
ANSWER:
C - the sperm dies when it reaches the female tract
If you need help with any more problems, feel free to message me and I'd be more than happy to help you work through them and provide explanations.
Hope this helps!! :)
If there's anything else that I can help you with, please let me know!
B positive patients can receive blood from B positive, B negative, O positive and O negative donors.
Some questions that can be answered by <em>Science</em> is:
-Is it possible to give nature and have shelter on other planets?
-What caused the global-warming?
-How can plane's fly?
Answer: When the city/county/state/region declares a drought and stops the use of water on lawns, the green stuff dies.The guy with the drought resistant set up will hardly notice any difference in the look of his yard.
Explanation:
In population genetics, gene flow (also known as gene migration or allele flow) is the transfer of genetic variation from one population to another. ... In some cases migration may also result in the addition of novel genetic variants to the gene pool of a species or population.