Dear student.
a. In the process of respiration, glycolysis occurs in the cytoplasm of the cell.
Glycolysis is the process which occurs in cytoplasm of all living organisms. In glycolysis one molecule of sugar is broken down into two molecule of pyruvate producing net two molecules of ATP, two molecules of NADPH and two molecules of water. In anaerobic organisms glycolysis is known as fermentation.
b. Lactic acid is the end product of anaerobic respiration in animals. This lactic acid can have different fate such as can be converted back to pyruvate which can enter oxidative phosphorylation, can be converted back into glucose via gluconeogenesis or even can be used to produce amino acids.
Regards.