Initial evidence is usually gathered by using Collection tools
I would have to say predation.
Cells need to intake things like nutrients, water, and oxygen, and they need to be able to export things like metabolic products and waste materials. No matter which direction the material is moving in, it needs to cross the cell membrane at some point.
Answer:
The charges inside and outside of the neuron before receiving a stimulus are negative and positive, respectively, which corresponds to the transmembrane rest potential.
Explanation:
Neuron is the specialized cell of the nervous system in charge of transmitting electrical impulses. The generation of a nerve impulse in the form of an electric current is due to a change in the transmembrane potential.
<u>Outside the neuron cell, electrical charges are predominantly positive, and the ion with the highest concentration is sodium. In the intracellular space, a great quantity of proteins provide negative charge, and there is a predominance of potassium ions</u>. Under these conditions, the ionic channels are closed.
For this reason, a neuron at rest, before receiving a stimulus, presents positive charges on the outside and negative charges on the inside, and the membrane potential in this condition is estimated at a value of -65 mV.
Once a stimulus is produced, the ionic channels open and Na+ ions enter the cytoplasm, exchanging them for K+, which implies a change in the membrane potential which, on reaching the threshold, produces an action potential and the nerve impulse is produced.
Answer:
Taking more samples from different parts of an acre.
Explanation:
Validity and accuracy of the data is crucial for any serious research. In this particular case, the most accurate data would be obtained if earthworms would be counted on the whole acre. Of course, this would consume lot of time, people, money etc. That's why methods for estimation are used. Estimation best works with large number of samples. Since one acre equals over 4000 square meters, taking only five samples from such a big area is simply not enough for obtaining valid data.
One of the possible ways to improve estimation is to take more samples per acre while avoiding taking adjacent samples because it could be possible that number of earthworms in one part of an acre is increased (or decreased) for any reason, which would lead us to wrong conclusion.
