There are different categories you can pick from example Predation
It sends an electrical impulse to make your heart beat. The job of a pacemaker is to artificially take over the role of your sinus node if it isn't working properly. Electrical impulses are sent by the pacemaker to stimulate your heart to contract and produce a heartbeat
<span>Both of them are example of Passive transport and Passive processes; If that's the type of answer you are looking for.</span>
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Transmitted, vertical
A transparent specimen is viewed through a microscope using transmitted light while an opaque object requires vertical illumination.
Transmitted light is the light that passes through an object. Transmitted light microscopy is any kind of microscopy in which the light is transmitted from a source located directly across the specimen from the objective. The light is commonly passed through a condenser in order to focus it on the specimen to obtain very high illumination. After the light passes through the specimen, the image of the specimen moves through the objective lens and later to the oculars where the enlarged image is viewed.
Answer: absolute certainty is often difficult to achieve. Scientific uncertainty generally means that there is a range of possible values within which the true value of the measurement lies.
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