Why does darkness affect the light-independent reactions of photosynthesis?

plants stop their daytime activities and rest during the night much like animals do.

light independent reactions need more heat energy than nighttime temperatures often provide.

mitochondria produce sugars more effectively in the darkness than chloroplasts do.

light independent reactions require the energy gathered in the thylakoids.

What is the key to the recognition of codominance?

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?

Why are current extinctions of concern to enviromentalists?