You design an experiment to test the hypothesis that consuming caffeine increases a person's chances of developing a headache. P
articipants in the experimental group will be told to drink 8 ounces of caffeinated soda in the morning once a day for 10 days, and to abstain from drinking any other caffeinated beverages or soda. Which of the following is an appropriate control group for your experiment? a) A group that drinks 8 ounces of decaffeinated hot coffee (no caffeine) in the morning once a day for 10 days and abstains from drinking any other caffeinated beverages or soda
b) A group that drinks 8 ounces of caffeinated soda once a day for 10 days in addition to their normal beverage habits
c) A group that drinks 8 ounces of decaffeinated soda (no caffeine) in the morning once a day for 10 days and abstains from drinking any other O caffeinated beverages or soda.
d) A group that does not drink soda (caffeinated or decaffeinated) or other caffeinated beverages for 10 days
d) A group that does not drink soda (caffeinated or decaffeinated) or other caffeinated beverages for 10 days
Explanation:
In an experiment, two groups exist as follows: experimental group and control group. Experimental group is the group that receives the experimental treatment (independent variable) while the CONTROL GROUP is the group that does not receive the experimental treatment.
In this experiment, the experimental treatment is the CAFFEINATED SODA (contains caffeine). Hence, the appropriate control group for this experiment will be the group that does not drink any soda (whether caffeinated or decaffeinated) or other caffeinated beverages for 10 days.
Yes. Upper-layer skin cells and the cells in the front surface of the eyes get a significant amount of oxygen directly from the air rather than from the blood. Human bodies have a huge demand for oxygen. As a result, the oxygen that is able to passively diffuse into the body directly from the air is not nearly enough to run the whole body. Fortunately, we have lungs that can actively pull in oxygen and transfer it to the blood, allowing the body to transport oxygen to the cells by using the blood like a fleet of delivery trucks. Most of our cells rely on the blood delivery service. However, the cells in the outer layers or our skin and eyes are in direct contact with the atmosphere and can efficiently get their oxygen right from the air.
Yes, there are nuclear reactions constantly occurring in our bodies, but there are very few of them compared to the chemical reactions, and they do not affect our bodies much. All physical objects are made of molecules. A molecule is a series of atoms linked together by chemical (electromagnetic) bonds.
Photon wave phase can also not be directly detected by humans but can be detected by machines called interferometers. Phase information is often used to determine the flatness of a reflecting surface. In summary, humans can indeed see photons. Humans can see all of the properties of photons except for spin and wave phase.
In the eukaryotic cell cycle, chromosome duplication occurs during "S phase" (the phase of DNA synthesis) and chromosome segregation occurs during "M phase" (the mitosis phase).
