According to the endosymbiotic theory of the origin of eukaryotic cells, how did mitochondria originate? From engulfed, originally free-living bacteria
When a protoeukaryote engaged in a symbiotic relationship with a protocell by secondary endosymbiosis
From the nuclear envelope folding outward and forming mitochondrial membranes
From infoldings of the plasma membrane, coupled with mutations of genes for proteins in energy-transfer reactions

i can't see the full page, therefore, can't answer it

explanation:

answer; i believe the answer is hydraulic action;

answer: substrate concentration. enzymes work best when there is a high enough substrate concentration for the reaction they catalyse.

the two answers are a, the population of birds with large beaks will increase on the island, and c, the trait for large beaks will be passed on to future generations through natural selection. the reason for that is because if the birds that have beaks developed for eating small seeds lose all of their food, they will go hungry and eventually starve because they physically cannot eat the large seeds, therefore making the population of large beaked birds higher. also, if the trait of large beaks are dominant on the island over small beaks, then over time the large beaked birds will reproduce more and more, while the smaller beaked birds will reproduce less and less because they can't survive with the food provided. that leads to the trait of small beaks disappearing and the trait of large beaks taking over the island.