What are the main types of cellular work? How does ATP provide the energy for this work?

Verified step by step guidance

1. Identify the three main types of cellular work: chemical work, transport work, and mechanical work. Chemical work involves endergonic reactions such as the synthesis of polymers from monomers. Transport work includes the pumping of substances across membranes against the direction of spontaneous movement. Mechanical work involves physical movements like the contraction of muscle cells or the movement of chromosomes during cellular reproduction.
2. Understand the structure of ATP (adenosine triphosphate), which consists of adenine, a ribose sugar, and three phosphate groups. The bonds between these phosphate groups are high-energy bonds.
3. Learn how ATP provides energy for cellular work. When ATP is hydrolyzed, it loses one phosphate group and releases energy, forming ADP (adenosine diphosphate) and a free phosphate group. This reaction is exergonic and releases energy that can be used by the cell.
4. Explore how the energy released from ATP hydrolysis is coupled to cellular work. This process is known as energy coupling. The cell uses the energy released during ATP hydrolysis to drive endergonic reactions or processes that require energy, effectively linking the exergonic process (ATP hydrolysis) with the endergonic process (cellular work).
5. Examine specific examples of how ATP is used for each type of cellular work. For chemical work, ATP provides the energy to form bonds in molecule synthesis. In transport work, ATP is used to change the shape of transport proteins in the cell membrane, allowing substances to move against their concentration gradients. For mechanical work, ATP is used for movements like muscle contractions or the movement of vesicles within cells.

Video transcript

Welcome back. Let's look at our next question. It says the skeletal muscle cells have little stored a teepee, which they can use immediately which of the following A. T. P. Sources can supply them with immediate 80 P. At a very high rate to keep them working. So we have four answer possibilities. There are all sources of a T. P. But we're looking for which of these four things can supply muscle cells with immediate 80 P at a very high rate. So let's look at our four choices. They are a glycogen, be fat reserves. See creatine phosphate and D. Protein. And what we're looking for is for C. Creatine phosphate. Creatine phosphate is a foss for elated form of creatine. That is a rapid reserve of high energy phosphate. So the high energy phosphate group from creatine phosphate can be used to make a teepee from ADP very rapidly in skeletal muscles and it can supply the energy needed for working muscle at a very high rate but only for about 8 to 10 seconds. So this is kind of the immediate bam right away tons of a teepee but not for long term usage. But it is what we're looking for is immediate a TP at a very high rate. So that's creating phosphate. Let's just look at our other answer choices to understand why they're not correct. We've got choice a glycogen and glycogen. Of course, we know uh from our content video that glycogen is a carbohydrate used for storage. Um it's made up of glucose units. So it can be broken down to make a T. P. From glucose. So the glycogen can be broken down into glucose which can be broken down for A. T. P. However this takes about 12 chemical reactions to produce the A. T. P. So it supplies energy a bit more slowly than the creatine phosphate. So it's slower than the creatine phosphate. It's not the immediate source of a teepee. So it's there, its reserves of energy but not immediate. So not our answer. And then finally. Choice B. And choice de fat reserves and protein. Both fat reserves and protein can be used when oxygen is present for aerobic respiration. And that also involves the breakdown of glucose to produce A. T. P. But this involves even more chemical reactions than the breakdown of glycogen. Um glycogen you just have, it's a polymer of glucose. So that's a more direct process aerobic respiration as we recall the whole um cyclical process much longer. So this is much slower then glycogen however, it's useful because as long as you have oxygen available it can keep on producing A. T. P. For hours or longer um As long as that oxygen is available. And that cycle can keep going. So it's more of the long term a TB source. But it's not our answer. Neither B nor D. Because again we're looking for an immediate source of a TP at a very high rate for those skeletal muscle cells. And that is choice. See creatine phosphate. See you in the next video.