The mechanisms of reproductive isolation prevent the reproduction of two individuals from different species. The prezygotic mechanisms disrupt the stages of reproduction before the forming of the zygote or prevent the mating at the start, and the postzygotic mechanisms affect the stages of reproduction after the forming of the zygote.
So, the first and the third example (the urchins and the grasshoppers) show the prezygotic mechanism, as the two individuals are not able to mate or form a zygote.
The second and the fourth example ( zonkey and the death of a zygote) show the working of the postzygotic mechanisms, as the zygote is formed, but it seems to be inviable, and the zonkeys are sterile, preventing the individual to reproduce.
Answer:
2B
4E
3C
1D
Explanation:
This is the answers, a plant cell has chloroplast and mitochondria because is autotrophic(makes food)
The answer is D. Transports fluids throughout the plant.:)<span>
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Answer: reading paper books and magazines, sleeping in beds under cotton sheets, having a sandwich for lunch
, sitting at wooden desks
, I picking wildflowers
, eating a favorite breakfast cereal.
Explanation: These are all correct because each has to deal with plants. For example, reading the paper books, sleeping in the bed and sitting at the wooden desk all have to due with the products that come from plants. Paper, cotton, and wood are all grown from plants and turned into resources. Next picking flowers, eating foods are also direct examples of how plants help us. Picking flowers that come directly from plants. Then eating food that is grown from plants shows that it is directly plants providing for humans.