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!
The reason for this is because it is closer to water, therefor they have more events that could happen. Also there is a lot of weathering, erosion, and deposition which makes the gulf coast prairies and marshes more susceptible to changes.
I hope this helps!
Volume of a cylinder formula:
V= h(pi×r^2)
If the diameter is 10in, then the radius is 5in
Substitute given values into the formula:
V=20(3.14×5^2)
V=20(78.5)
V=1570in
I believe the answer is this:
DNA replication is called semi-conservative because half of the original double-helix appears in one daughter strand formed in replication if you need any more help then please comment and let me know ok. :)
Number 2 but I am not sure sorry dude