Its common. In the last 10 million years, there have been 4 or 5 reversals per million years
Human forelimbs is used for a variety of functions, such as for eating.
Similarities: They are all made from the same basic anatomical structure classified as homologous structures.
They all have this structure inherited from a common ancestor.
The statement which best explains why carbon is present in so many kinds of molecules is because <u>it can form four covalent bonds.
<em /></u>It isn't rare on Earth, so A is incorrect. It has valence electrons, so C is incorrect. It cannot become an ion, so D is incorrect.<u>
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Answer:
Ferns do not have true leaves as many plants do, but structures called fronds. These fronds are split down into leaflets called pinnae. These fronds are green and the fern gets its food via photosynthesis. Ferns reproduce by spores in an alternating generations.
Explanation:
i studied ferns for years
Plates collide causing rock to push upward together