In humans, not having freckles (f) is dominant to having freckles (f). not having a cleft chin (c) is also dominant to having a cleft chin (c). which statement is true of the offspring of a cross between parents that are both heterozygous for both traits (ffcc)?

Blood has traveled from the heart to the toes. which describes the next step of the circulation process?

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?

Which of the following describes what an activator an enhancer are