The fossil evidence found in these sedimentary layers best implies that a) land plants are older than land animals. b) vertebrates and invertebrates evolved together. c) invertebrates lived on earth before vertebrates. d) land animals evolved at the same time as marine animals

The reactions that occur in the ribosome, where amino acids are combined to form proteins are anabolic or catabolic?

Awave has a wavelength of 15 mm and a frequency of 6 hertz. what is its speed?

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?