Answer:
Control group: volunteer stationary bike riders in a pollution-free chamber
Experimental group: volunteer stationary bike riders in a chamber filled with air pollutants common to Los Angeles
Independent variable: exposure to air pollution
Dependent variable: The heart rates (physical fitness) of the volunteer riders.
Explanation:
In a scientific experiment, data is compared between the control group and experimental group to ascertain the effect of the independent variable on the dependent variable. A control group is the group in an experiment that is not treated with the independent variable i.e. the independent variable is controlled while the experimental group is the group that is treated with an independent variable.
N.B: The independent variable is the variable controlled by the experimenter in order to influence the dependent variable (measurable outcome).
In this experiment, the independent variable is the AIR POLLUTION the volunteer riders are exposed to while the dependent variable is the PHYSICAL FITNESS/ HEART RATES of the volunteer riders, which is dependent on the exposure to air pollution (independent variable).
The control group in this experiment is the volunteer riders placed in a POLLUTION-FREE CHAMBER where the independent variable cannot influence or have any effect on the measurable variable (dependent). The experimental group is the volunteer riders placed in a CHAMBER FILLED WITH AIR POLLUTANTS. The independent variable (air pollution) has been changed in the experimental group.
All of those can potentially harm the earth. Human activity is a cause of pollution, and pollution is the cause of acid rain to some extent.
I think the answer is B because it happens slowly and through natural selection
Answer:
True
Explanation:
Tetrodotoxin is the molecules that act as a poison to the organism in which they are injected.
The tetrodotoxin proves lethal to the organisms as it kills the organism by interfering with the nervous system. The tetrodotoxin blocks the sodium channels in the neuron as a result of which the sodium is unable to enter the neurons and hence the electrical impulse is not generated.
If the tetrodotoxin blocks the motor neuron transmission by blocking the sodium channels then the signals will not reach the muscle and muscle will not be able to contract.
Thus, true is correct.
Hormones are a group of chemicals released by exocrine glands

These hormones are directly secreted into bloodstream from where they reach the site.