Evolution has led giraffes to have very long necks. Trees in the savannah have less leaves on bottom branches because of other animals. For the giraffe to survive, their necks slowly became longer as they could eat more leaves from upper/top branches. If they had not evolved longer necks, they would not exist today.
Answer:
Cell walls never take the place of a cell membrane
Explanation:
The correct answer is scanning electron microscope and scanning tunneling microscope.
The SEM refers to a kind of electron microscope, which generates three-dimensional images of a specimen by scanning the surface with a focused beam of electrons. The electrons associated with the atoms in the specimen, generating different signals, which comprise data regarding the composition of the specimen and the surface topography.
An STM refers to an apparatus for imaging three-dimensional image surfaces at the atomic level. In this, good resolution is regarded to be 0.01 nm depth resolution and 0.1 nm lateral resolution.
The STM can be utilized not only in a high-ultra vacuum but also in water, air, and numerous other gas or liquid ambient, and the temperatures spanning from 1000 degree Celsius to zero Kelvin.