Answer: Natural selection is one of the forces of evolution and the enviroment where the species lives is the selection agent. For example, suppose a mosquitoes population in a environment free from insecticides, in this environment there's a high frequency of non-resistant mosquitoes because the environment is not exerting any pressure on the resistence trait. But when the environment changes and we use a insecticide upon the mosquitoes population, the populations changes because the non-resistant ones die but those resistant survive and beggin to reproduce more effectively. That's natural selection, differences in survival and reproduction between individuals with different phenotypes (traits) and this differences depend of environmental changes.
Double layered nuclear, the outer nuclear membrane is continuous with the membrane of the rough endoplasmic reticulum (ER), it also continues with the inner nuclear membranes since the two layers are fused together at a numerous tiny holes called nuclear pores that perforate the nuclear enevelope
A group of same kind of cell is called tissue
Answer:
The rock cycle is a constant transformation of rocks between the three rock types of igneous, sedimentary, and metamorphic. If the sediments are buried behind other layers of sediment, they can lithify and form sedimentary rock. When rocks melt, magma is formed. Rocks form deep below the Earth, move and sometimes change, rise to the surface, and eventually return to their original location.
