Cellular respiration is considered to occur in three phases: I _______________ I

Question

Cellular respiration is considered to occur in three phases:

              I _______________

              II_______________

              III_______________

       The first phase of Cellular Respiration is called _______________. In it, Glucose, a 6 carbon _______________ (name of the biomolecule category it is in) is eventually broken up into two molecules of _______________. Also produced are _______________ and the electron carrier _______________. This phase takes place in the _______________ (cellular location).

       The second phase of Cellular Respiration starts with the _______________ from the first phase losing a CO2 as it is converted into a molecule of _______________. This molecule then enters the _______________ Cycle. Here, through a series of enzymatically catalyzed reactions, more molecules of _______________ are released and molecules of _______________ and _______________ are produced that are used in the last phase of Cellular Respiration. The _______________ Cycle takes place in the _______________ of the _______________ (cellular location).

       The final phase of Cellular Respiration is called _______________, and takes place in the _______________ of the _______________ (cellular location). Electrons carried by _______________ are passed to membrane bound proteins that attract _______________ ions establishing a concentration _______________. The membrane bound protein channel/enzyme, _______________, can ‘tap’ into this concentration _______________ and produce _______________ from _______________ and _______________.

       The terminal electron acceptor in this phase is _______________, which is converted into _______________.

       If an organism can’t complete Cellular Respiration due to a lack of a terminal electron acceptor, glycolysis can still go on and _______________ can be produced. But in order for electron carriers to be recycled, pyruvate can be converted into lactic acid, acetic acid or _______________ (depending on the type of organism). This anaerobic respiration is called _______________.

Explanation / Answer

Cellular respiration is considered to occur in three phases:

              I Glycolysis

              II the Kreb's Cycle

              III Electron Transport Chain or Oxidative Phosphorylation

       The first phase of Cellular Respiration is called Glycolysis. In it, Glucose, a 6 carbon Hexose (name of the biomolecule category it is in) is eventually broken up into two molecules of pyruvate. Also produced are ATP and the electron carrier NADH. This phase takes place in the cytoplasm (cellular location).

       The second phase of Cellular Respiration starts with the pyruvate from the first phase losing a CO2 as it is converted into a molecule of acetyl-coenzyme A. This molecule then enters the Citric acid Cycle. Here, through a series of enzymatically catalyzed reactions, more molecules of ATP are released and molecules of NADH and FADH2 are produced that are used in the last phase of Cellular Respiration. The Citric acid Cycle takes place in the matrix of the mitochondria (cellular location).

       The final phase of Cellular Respiration is called oxidative phosphorylation. and takes place in the inner mitochondrial membrane of the mitochondria (cellular location). Electrons carried by NADH and FADH2 are passed to membrane bound proteins that attract H+ ions establishing a concentration gradient. The membrane bound protein channel/enzyme, ATP synthase, can ‘tap’ into this concentration gradient and produce ATP from ADP and Pi.

       The terminal electron acceptor in this phase is oxygen, which is converted into water.

       If an organism can’t complete Cellular Respiration due to a lack of a terminal electron acceptor, glycolysis can still go on and ATP can be produced. But in order for electron carriers to be recycled, pyruvate can be converted into lactic acid, acetic acid or ethanol (depending on the type of organism). This anaerobic respiration is called fermentation.

Related Questions

Navigate

• Browse (All)
• Browse C
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.