What needs to happen to genetic material in order for cells to reproduce?

Dermal tissue in plants stores 1.extra food 2.transports water and nutrients 3.transports waste materials 4.is similar to epithelial cells in animals

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 environmental change would most likely result in bullfrog offspring that are able to store more water than bullfrogs in previous generations?