Answer:
It represents the four nitrogenous bases found in DNA.
Explanation:
The numbers 1 to 4 represent guanine, adenine, thymine and cytosine.
Katie has a rare neurological disease in which her neurons can receive new information and process it, but some of them just cannot pass the information along. This disease most likely affects the axon of the neurons. Since axon is the signal transmitting end of the neuron, if the fusion of the vesicles containing the neurotransmitters with the cell membrane around the synaptic cleft is hampered, then the signal transmission gets disrupted.
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.