Answer:
d is correct answer to your question
The author supports the statement by explaining the different theories about yawning, this includes theories and some that are still studied.
The author states that scientists have not yet reached any consensus regarding theories about why humans yawn and argue this claim by explaining the following theories about yawning:
- In Antiquity: Hippocrates' Yawning Theory focused on the respiratory system by hypothesizing that yawning precedes fever and is a way of removing polluted air from the lungs.
- In the seventeenth and eighteenth centuries: Most theories focused on the circulatory system. These theories posited that yawning causes an increase in blood pressure, heart rate, and oxygen in the blood.
- Today: Dr. Robert Provine, in 2005 stated that yawning is associated with changing a state of behavior.
- Gallup in 2008 proposed that yawning is related to a way of cooling the brain's temperature.
- In 2011, Dr. Andrew Gallup and Omar Tonsi Eldakar stated that yawning is related to the outside temperature, that is, when the temperature is warm, the body yawns less frequently.
According to the above, it can be inferred that scientists have not reached a consensus on yawning because all have raised different theories to explain its function.
Learn more in: brainly.com/question/8945611
Chloroplasts - found only in plants and algae. they convert solar radiation energy to chemical energy usable for the cell's metabolism.
mitochondria - found in both plants and animals, they produce energy (in the form of ATP - chemical compound) by decomposing sugars and fats. they use up oxygen to do it.
Answer: Division chlorophyta: Green Algae. Division phaeaphyta: brown algae Division Rhodophyta: red algae
Explanation:
The wave period is the amount of time it takes a wave to
pass a point. Wave frequency is what you
call the number of waves that pass in a certain point per second. If you
increase the wave length of any wave, you decrease the wave frequency (the
number of waves that pass in a certain point per second).
