Answer:
Environmental changes.
Explanation:
If you change the habitat they are used to they might not adapt in time causing their species to die down and they could come close to extinction.
Through meiosis, diploid parents produce haploid cells called gametes. The gametes, through sexual reproduction, then meet and join into one cell called a zygote that is diploid.
The zygote then develops into a diploid organism with genetic traits from both parents.
Even though amoeba, paramecium, and spirogyra are quite different, they are all often classified in the same group, Protista because this group holds various types of eukaryotic organisms that are heterotrophic and unicellular.
This type of classification is not based on evolutionary and genetic similarities, but only on the properties of being unicellular, so there are many vastly different organisms in this group.
A sickled cell has more of a "banana" shapped curve.
This curve often gets stuck in blood vessels, causing a clot
They capture the reflected infra red rays
