Answer:
It is necessary to separate oxygenated and deoxygenated blood separate in mammals and birds to maintain their body temperature. Also, if they both are mixed, the blood will get impure and it would be difficult for the heart to supply impure blood. We also can't live with impure blood so we most probably will die.
Find latitude and longitude
The basic repeating unit of nucleic acids are known as nucleotides. A nucleotide consists of three distinct chemical groups, a 5-carbon sugar (ribose or deoxyribose), a nitrogen-rich base - (cytosine (C), guanine (G), adenine (A), thymine (T) in DNA or uracil (U) instead of T (in RNA), and phosphate.
Could you add the picture please?
C) 1 and 4
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