1. Action potential reaches the axon terminal and depolarizes it.
2. Depolarization opens voltage-gated calcium channels, enabling influx of Ca into the neuron.
3. Calcium binds to specialized proteins on vesicles (containing pre-made acetylcholine) and triggers them to fuse with the neuron membrane at the synapse.
4. Exocytosis of acetylcholine into the synaptic cleft occurs.
5. Acetylcholine diffuses across the synapse and binds to nicotinic receptors on the end plate of the myocyte.
6. Activated nicotinic receptors, themselves ion channels, cause cation influx into the myocyte and generate an end plate potential. This eventually gives rise to the full depolarization within the myocyte that enables contraction.
Human trials have indicated an inverse relationship between blood lead level and calcium intake. While milk isn’t an antidote to let’s say, lead poisoning, the dietary calcium inhibits the lead absorption. This sort of poisoning is incredibly dangerous to the systems of the human body, and the ingredients within the milk help to defend against it. The purpose of the milk is to dilute the ingested poison.
The independent variable is the amount of water consumed by the football players.
The dependent variable is the football players' endurance, measured by how many times they can run up and down the bleachers before catching their breaths.
The coach's hypothesis was that the more water consumed, the more endurance the players will have.
There is not a control group present in this experiment, but it would be the set of players who did not drink a bottle of water before practice.
The experimental group is the set of players who did drink a bottle of water before practice.
The constants in the experiment are the operational definitions of endurance (how he measures their endurance), the amount of water each player drinks throughout the week, and the players used in the experiment.
The lack of a set control group poses a threat to the accuracy of the experiment's results.
Because of the fresh water shortage