Gas molecules across the membrane
It can be water molecules as well
False sports drinks are supposed to last up to 2 hours
Answer:
None of the options provided is correct but some are close
Explanation:
One of the ways in which a cell maintain homeostasis is by regulating what goes in and out of the cell through the cell membrane (which is a semi-permeable barrier). The amount of water is highly regulated by the cell in this case so as to regulate osmosis (movement of water molecules from a region of higher concentration to a region of lower concentration). Other substances regulated are oxygen and carbon dioxide.
NOTE: The cell <u>does not create water molecules neither does it use carbon dioxide to maintain homeostasis</u>, it rather regulates these two compounds.
Answer:
Most people experience increased infant mortalities at high altitudes due to the inability of the mother to provide sufficient oxygen to the developing fetus but now variation in the DNA sequence in the people that lives at higher altitudes like in Tibetans allow normal level of infant survival at high altitudes.
This variation occurred in the EPAS1 gene in the Tibetan population that is responsible for delivering oxygen more efficiently to the fetus. This nucleotide variation is also present in low landers of Beijing but natural selection selected the variant gene in Tibetan people because they require this mutated gene for their survival.
So the population passed this variant gene in next-generation, therefore, inheritance allowed the spreading of the mutated gene to the next generation therefore by natural selection and inheritance a mutated gene spread through a human population that had just begun living high in the mountains.
