Answer:
Because Circumpolar constellations are constellations that never set below the horizon when seen from a particular location on Earth.
They can be seen in the night sky throughout the year, while other constellations are seasonal, visible only at certain times of year.
The term circumpolar refers to constellations and stars that are circling the north and south celestial poles without ever dipping below the horizon. All circumpolar constellations are found near the celestial poles and, due to their proximity to the poles, they never disappear from view.
The five northern constellations visible from most locations north of the equator throughout the year are Cassiopeia, Cepheus, Draco, Ursa Major, and Ursa Minor.
The three southern circumpolar constellations visible from most locations in the southern hemisphere are Carina, Centaurus, and Crux.
Other constellations are just as prominent in the sky and can be seen for most of the year, but only these eight are circumpolar.
Upper epidermis. The cuticle on upper epidrrmal layer prevents excessive water loss
Answer:
B. "Whispered pectoriloquy" - "speaking from the chest"; used as a means of finding masses in the lung. The whispered word is audible in areas where fluid or a mass is present
Explanation:
Auscultation in medicine, is the action of listening to sounds from the heart, lungs, or other organs, usually using a stethoscope, in order to perform medical diagnosis.
Auscultation is performed for the purposes of examining the circulatory and respiratory systems, as well as the alimentary canal. The procedure is best performed in a quiet examination room. A stethoscope is used to magnify internal sounds. Small changes in breath sounds are carefully observed in order to make a diagnosis.
Whispered pectoriloquy is used to detect vocal resonance. It is used as a means of finding masses (consolidations e.g. pus) in the lung and is performed by having the patient quietly whisper a word. If fluid or a mass is present, words that are whispered may be heard clearly.
Oh this one is so cool!
It basically all boils down to Vitamin D! We need this essential vitamin to help our body build hormones and regulate calcium. Our bodies make Vitamin D when we are exposed to the UV rays found in sunlight. But as we all know, too much sunlight isn’t good because these UV rays can harm us. Melanin (the chemical that our bodies produce to darken skin tone and hair color) provides protection from UV rays by absorbing them. However, this means that the more melanin that is produced by someone’s body results in less absorption of UV rays and a decrease in Vitamin D production. But for someone living around the equator or in the tropics that doesn’t matter because there’s lots of sun all the time. So for humans living in these areas where there’s lots of sunlight year round, it’s beneficial to have darker skin to protect from the harm of UV rays. People living in these areas still get plenty of Vitamin D though because of that year round sunshine.
Now what about those who’s skin has less melanin, such as those found in the higher latitudes? Well with less sunlight year round, their bodies had to adapt to be able to get enough Vitamin D. So less melanin is produced by the body in order to absorb the lesser amounts of UV rays to make Vitamin D. Lighter skin is, therefore, more beneficial the farther away you go from the tropics.
So essentially:
Pro of Darker Skin tones
-Protection from harmful UV rays
Con of Darker Skin tones
-Less absorption of UV rays and less production of Vitamin D
Pro of Lighter Skin tones
-Greater absorption of UV rays and more Vitamin D production
Con of Lighter Skin tones
-Less protection from harmful UV rays (resulting in sunburns and, in extreme cases, skin cancer)
This is of course the biology answer. The social impacts of different skin tones is a whole different story that you can ask in the history section.
A group of cells that work together to perform a common function