Sugar molecules (i.e. glucose) are broken down into simpler molecules such as pyruvate. Pyruvate, in the presence of oxygen will be converted to Acetyl-CoA and it will enter the tricarboxylic acid cycle wherein it will produce series of reducing compounds such as NADH and FADH. These reducing compounds are then processed in the electron transport chain and oxidized, and the energy released in the oxidation of NADH and FADH is transferred to the high energy phosphate bond of adenosine triphosphate or ATP.
A baby animal knows what to do after birth just from natural instinct. Human babies do not get taught how to breath or cry, they know to do so because they would die otherwise.
The option which is not a characteristic of chordates is chloroplasts in their cells.
Chordates do have a dorsal supporting rod (vertebrates are types of chordates - they have a spine), a dorsal hollow nerve cord (within the spine), and pharyngeal pouches. However, they do not have chloroplasts, because that is a characteristic of photoautothropic eukaryotes, which chordates certainly are not.
So they can say the number quicker.
