Which of the following exercises would NOT be fueled with energy produced from the electron transport chain? A. Mowing the lawn
B. Sprinting the 100m dash
C. Walking to the grocery store
D. Running a marathon

Which of the following statements is false?
A. Glycolysis can occur with or without oxygen
B. Glycolysis is the first step in both anaerobic and aerobic respiration
C. Glycolysis occurs in the mitochondria
D. Glycolysis produces 2 ATP, 2 Pyruvates, and 2 NADH

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?