Cell Respiration Respiration is the process by which organisms burn food to produce energy. The starting material of cellular respiration is the sugar glucose, which has energy stored in its chemical bonds. You can think of glucose as a kind of cellular piece of coal: Just as burning coal produces heat and energy in the form of electricity, the chemical processes of respiration convert the energy in glucose into usable form.
Adenosine triphosphate ATP is the usable form of energy produced by respiration. ATP is like electricity: It has a ribose sugar attached to the nitrogenous base adenine. Each of the ATP phosphate groups carries a negative charge.
In order to hold the three negative charges in such proximity, the bonds holding the phosphate groups have to be quite powerful. If one or two of the bonds are broken and the additional phosphates are freed, the energy stored in the bonds is released and can be used to fuel other chemical reactions.
When the cell needs energy, it removes phosphates from ATP by hydrolysis, creating energy and either adenosine diphosphate ADPwhich has two phosphates, or adenosine monophosphate AMPwhich has one phosphate.
Respiration is the process of making ATP rather than breaking it down. There are actually two general types of respiration, aerobic and anaerobic. Aerobic respiration occurs in the presence of oxygen, while anaerobic respiration does not use oxygen.
Both types of cell respiration begin with the process of glycolysis, after which the two diverge. Aerobic Cell Respiration Aerobic respiration is more efficient and more complicated than anaerobic respiration.
Aerobic respiration uses oxygen and glucose to produce carbon dioxide, water, and ATP. More precisely, this process involves six oxygen molecules for every sugar molecule: Typically, the SAT II Biology only asks questions about the starting and ending products of each stage and the location where each takes place.
Understanding the internal details of stages will help you remember these key facts and prepare you in case the testers throw in a more difficult question, but the details of all the complex reactions will probably not be tested by the SAT II.
Glycolysis Glycolysis is the first stage of aerobic and anaerobic respiration. It takes place in the cytoplasm of the cell. The chemical formula for glycolysis is: The 2 NADH molecules travel to the mitochondria, where, in the next two stages of aerobic respiration, the energy stored in them is converted to ATP.
The most important things to remember about glycolysis are: Glycolysis is part of both aerobic and anaerobic respiration. Glycolysis splits glucose, a six-carbon compound, into two pyruvate molecules, each of which has three carbons.
Unlike the rest of aerobic respiration, which takes place in the mitochondria, glycolysis takes place in the cytoplasm of the cell. Unlike the rest of aerobic respiration, glycolysis does not require oxygen.
The Krebs Cycle After glycolysis, the pyruvate sugars are transported to the mitochondria. During this transport, the three-carbon pyruvate is converted into the two-carbon molecule called acetate.
The extra carbon from the pyruvate is released as carbon dioxide, producing another NADH molecule that heads off to the electron transport chain to help create more ATP. The acetate attaches to a coenzyme called coenzyme A to form the compound acetyl-CoA.
The acetyl-CoA then enters the Krebs cycle. The Krebs cycle is called a cycle because one of the molecules it starts with, the four-carbon oxaloacetate, is regenerated by the end of the cycle to start the cycle over again.
The Krebs cycle begins when acetyl-CoA and oxaloacetate interact to form the six-carbon compound citric acid.To begin the registration process, enter the first 6 letters of your access code below.
To begin the registration process, enter the first 6 letters of your access code below. AP Biology Reading Guide Chapter Community Ecology Fred and Theresa Holtzclaw. Since , CELLS alive! has provided students with a learning resource for cell biology, microbiology, immunology, and microscopy through the use of mobile-friendly interactive animations, video, puzzles, quizzes and study aids.
Name one keystone species, and explain the effect its removal has on the ecosystem. Explain facilitator or foundation species and give an example.. You may omit bottom-up and top-down controls. Scroll to the appropriate quiz below.
If you don’t have your textbook at home, use the links next to each question for links to your text online.