Answer: c
It says the answer needs to be 20 characters long)
The correct answer here is "cell membrane". Generally it makes sure that nothing enters or leaves the cell, except by its highly guarded "gates", such as ion channels, that let some particles through - but they're very picky about whom to let in!
D the formation of specicies
Answer:
C. At least five mass-extinction events have occurred during the last 500 million years.
Explanation:
- The history of mass extinct is related to the five mass extinctions that are caused over by the 350 million years n which many species have disappeared in there short geologic time.
- A massive extinction is caused in the Permian Triassic extinction event i.e about 250 mn years ago which on an estimate has killed 90% of the species.
- The Cretaceous–Paleogene extinction event that occurred over 66 million years ago is known to have wiped out the dinosaurs and many other species.
Answer:
Frozen
Explanation:
When it heats up water evaporates and when it's cold it does the opposite, it freezes because of the low temperature.
