An Introduction to Metabolism_Chapter 8

1. What are the forms of energy?

2. Explain the structure, function, and the regeneration of ATP.

3. How do enzymes work ?

1. Forms of Energy.

Energy is the capacity to cause change. 3 different energies; kinetic, potential and activation energy. If it is a relative motion of objects; kinetic. ex: moving objects, muscles in the body. there is heat or thermal energy. random movement of atoms and molecules.And object which is not moving has also energy. it has potential energy. this is; because of the objects location and structure. molecules have energy because of the arrangement of atoms.It is a stored energy.The initial investment of energy for starting a reaction is called activation energy. activation energy is often supplied by heat. the energy used to convert the potential energy into kinetic energy.

2. ADENOSINE TRIPHOSPHATE

(ATP). composed by three phosphate groups, one adenine nitrogenous base, and one ribose. (pentose sugar) it is used to build energy but also to make RNA. it is renewable energy source ant they are unstable bonds. ATP works by energizing other molecules by transferring phosphate groups.

Video on ATP :

http://www.youtube.com/watch?v=Lx9GklK0xQg&feature=related

3. Enzymes :

Enzymes speed up metabolic reactions by lowering energy barriers. so lower the activation energy.it would take much more time to solve a substance without the aid of enzymes. enzymes are proteins. it acts as a catalyst.

AB + CD ----> AC + BD

reactants---->products

here is the transition state.

substrate is the material that the enzyme works on. so basically the substance which need to be broken down. active site is the area that the substrate comes in. each substrate has a different and a specific active site that can fix just that substrate. enzymes are affected by the environment, cofactors, coenzymes, inhibitors and by allosteric sites.

5 main facts about this chapter :

. Metabolism is the totality of an organism's chemical processes.

. Catabolic Pathways break down complex molecules into smaller ones, releasing energy.

. Anabolic Pathways consume energy, build complex molecules from smaller ones.

. According to the first law of thermodynamics, energy can be transferred and transformed, but it cannot be created or destroyed.

. Second law of thermodynamics is that energy transfer or transformation increases the entropy of the universe.

In this chapter, we were introduced The Metabolism. We learnt the role of ATP on cell energy, the job of enzymes, and the two main laws of thermodynamic.