Based on the location of nitrogen (N) on the periodic table, how many additional electrons does a nitrogen atom need in its valence shell to satisfy the octet rule when it forms bonds? one
three
five
eight

How do environmental factors influence genetic traits? a. environmental factors determine all genetic traits. b. environmental factors can determine if a genetic trait becomes a health issue. c. environmental factors are determined by genetic traits. d. environmental factors have no influence on genetic traits. select the best answer from the choices provided

Ascientist separates a population of mice into two groups. what would most likely increase the rate of speciation in this population. a. teach the two groups different tricks b. allow the two groups to breed with each other c. put the two groups in different environment d. have the two groups live in identical ecosystems

Astudy by solloch and et. al., in 2017, gives the map above which shows the frequency of alleles with a ccr5-delta32 mutations over 87 different countries. this mutation deletes the presence of a co-receptor (ccr5) on the outside of human t-cells (lymphocytes). some viruses, such as the one responsible for the black death and human immunodeficiency virus (hiv), require this receptor for attachment to host cells during the infection process. the black death was an epidemic that passed over northern europe during the 14th century killing nearly 60% of europeans. according to this information, which explanation best explains why northern europeans show a greater immunity for hiv than some other parts of the world?