Which of the following best describes the main purpose of the combined processes of glycolysis and cellular respiration? 1 breaking down atp, so that adp and p can be reused2. producing complex molecules from chemical building blocks3 the breakdown of glucose to carbon dioxide and water4 transforming the energy in glucose and related molecules in a chemical form that cells can use for work5 catabolism of sugars and related compounds

4. transforming the energy in glucose and related molecules in a chemical form that cells can use for work

Explanation:

Glycolysis breaks down glucose into two molecules of pyruvate which is transformed into acetyl CoA to enter the Kreb's cycle. Kreb's cycle breakdown the acetyl CoA into CO2 and H2O. The energy stored in the glucose molecule is released during glycolysis and Kreb's cycle. The released energy is stored in the form of NADH and FADH2 as well as in few molecules of ATP.

The NADH and FADH2 enter the final step of cellular respiration, the oxidative phosphorylation. Here, NADH and FADH2 are oxidized with the help of electron transport chain (ETC). During the transfer of electrons through ETC, the proton motive force is generated which then helps in ATP synthesis.

Hence, the three steps of cellular respiration (glycolysis + Kreb's cycle + oxidative phosphorylation) retrieve the energy from nutrients such as glucose and store it in the form of ATP. ATP is used by cells as an energy source for various other functions.  

prophase: we can observe the chromosomes to coil up and condense. they become visible. nuclear membrane and envelope disintigrate.s

metaphase: chromosomes align at the center, the metaphase plate. spindle fibers attach to centromeres of the sister chromatids. they meet at kinetochores.

anaphase: sister chromatids are pulled towards each opposing centromere, set on different poles.

telophase: chromosomes are now clustered up only on either sides of the cell. nuclear membranes reform, and a new cell wall forms along the cell plate. this will lead to cytokinesis, the process that divides the cell membrane and forms the cell wall.