Question

give the pathway by which breakdown of glucose molecules takes place

Answer 1

The process of breakdown of glucose molecules involves two major stages - glycolysis (anaerobic respiration) and aerobic respiration ( Kreb’s cycle and ETS Pathway).

Glycolysis

Cellular respiration begins at this stage in the cytoplasm of the cells, and yields 2 carbon-based molecules called pyruvate, and 2 molecules of ATP. Oxygen plays no part during this stage, so it is called anaerobic respiration.

• Glycolysis is the metabolic pathway that converts one Glucose molecule into 2 molecules of Pyruvate.
• Glycolysis occurs when the cell needs energy and it takes place in the cytoplasm.
• Glycolysis, the linear pathway, occurs in (cytosol of all eukaryotes) animals, Plants and in the microbial cells. Glycolysis yields two molecules of ATP, two molecules of pyruvic acid and two electron carrying molecules of NADH.
• Glycolysis can occur with or without oxygen. In the presence of oxygen, glycolysis is the first stage of cellular respiration. In the absence of oxygen, glycolysis allows cells to make small amounts of ATP which is known as fermentation process.

Aerobic Respiration

• This process takes place in specialized structures within the cell called mitochondria, and uses the products of glycolysis.

• The energy released is stored in the form of ATP molecules. Usually, a total of 38 ATP molecules are produced.

Breakdown of glucose: C6H12O6 + 6O2 ------> 6CO2 + 6H2O + Energy.