Answer:
Angiosperms have seeds with an 3n endosperm due to double fertilization.
Explanation:
- Double fertilization is found only in flowering plants.
- In angiosperms, the female gametophyte does not grow after reaching eight nucleate stage.
- After fertilization and triple fusion, the zygote and primary endosperm are created and further growth of embryo sac continues.
- Triple fusion is the fusion of two haploid polar nuclei of female gametophyte and one male nuclei. This results in a 3n nucleus.
- The developing embryo obtains nutrition from the endosperm.
- If fertilization fails no endosperm is formed.
I believe it is C) calcium-rich plates echinoderms and B) bones in mammals like vertebral
Aluminum is 15 and copper is 35
I'm not totally sure. But in my view, <span>(4)a salt solution</span> would be used to prove that the gas produced by the yeast in the vacuum bottle could change the pH of the liquid in the flask
