3.5: Physiology of the GI Tract Part II: Cell Metabolism Flashcards
______ is a set of chemical reactions that are essential for the body to sustain life.
Metabolism
Metabolism is…….
Metabolism is a set of chemical reactions that are essential for the body to sustain life.
______ is the set of reactions in which smaller molecules are combined to make larger, more complex molecules.
Anabolism
Anabolism is……
Anabolism is the set of reactions in which smaller molecules are combined to make larger, more complex molecules.
______ is the set of reactions in which larger molecules are broken down to be used as energy sources for the body.
Catabolism
Catabolism is…….
Catabolism is the set of reactions in which larger molecules are broken down to be used as energy sources for the body.
the ______ process is often used during growth and repair phases of the cell.
anabolic
The most widely used form of energy in the cells is ______.
adenosine triphosphate or ATP
If a phosphate group is removed from ATP it becomes ______.
adenosine diphosphate or ADP
ATP has energy to___1___, while ADP can ___2___ energy (phosphate group) to become ATP.
- donate
- accept
By donating available phosphate groups, ATP transfers energy from ___1___ reactions to be used for___2___.
- catabolic (breaking down)
- anabolism (building up)
______ is defined as the process by which cells generate ATP.
Cellular respiration
what is Cellular respiration?
Cellular respiration is defined as the process by which cells generate ATP.
Most organisms carry out aerobic respiration, which requires ___1___ and releases ___2___,___3___, and ___4___.
- oxygen and a fuel (glucose, for example)
- carbon dioxide
- water
- ATP
___1___ are the main source of energy for cells with the body digesting carbohydrates into ___2___.
- Carbohydrates
- glucose
True or False: Glucose metabolism is used by the body primarily during high energy demands.
True
True or False: As glucose is one of the most abundant biomolecules, the catabolism of glucose is an important metabolic pathway used by microorganisms for ATP production.
True
What is the chemical make up of glucose?
C6H12O6
The complete catabolism of a single molecule of glucose (C6H12O6) yields up to ______ ATP and involves three distinct transitions.
38
What are the steps to glucose metabolizing?
- glycolysis (2 ATP)
- fermentation or respiration (2 ATP)
- electron transport chain produces 34 ATP via an oxidative phosphorylation event at the plasma membrane.
______ begins with the breakdown of a single molecule of glucose into two pyruvate molecules.
Glycolysis
______ is an aerobic process (oxygen must be present) used by cells to produce energy.
Cellular respiration
What is Cellular respiration?
Cellular respiration is an aerobic process (oxygen must be present) used by cells to produce energy.
Respiration takes place inside and around the double membrane-enclosed organelle known as the ______.
mitochondria
Fermentation, on the other hand, takes place in the absence of ______.
oxygen
The central pathway of respiration is called the ______.
tricarboxylic acid (TCA) cycle, also known as the Krebs Cycle or the citric acid cycle.
In the TCA cycle, the pyruvic acid (product of glycolysis) is converted to ______ forming some additional ATP.
carbon dioxide
At its conclusion, the TCA cycle produces ___1___ ATP in total (one for each pyruvate processed) and an abundance of electron carriers, known as ___2___.
- 2
- NADH and FADH2
What is the primary function of the TCA cycle?
The production of electron carriers, known as NADH and FADH2, as the transfer of these electrons will fuel the generation of ATP via the electron transport system.
As electrons are transferred from NADH/FADH2 to ______, energy is released and captured by electron acceptor proteins located in the inner membrane of mitochondria.
terminal electron acceptors (O2; aerobic respiration)
Electrons are then passed down a chain of electron acceptors (thus the name) causing ______to be pumped out of the membrane.
protons (H+; positive charge)
The ___1___ drives H+ back through the ___2___, also located in the membrane, resulting in the production of up to ___3___ molecules of ATP.
- proton motive force
- ATP synthase complex
- 34
Under aerobic conditions (in the presence of oxygen), the complete catabolism of glucose yields ___1___ ATP from glycolysis, ___2___ ATP from the TCA cycle and ___3___ ATP from the electron transport system, for a total of ___4___ ATP from a single glucose molecule.
- 2
- 2
- 34
- 38
______ occurs in the liver by a process known as beta-oxidation.
Lipid metabolism
Lipid metabolism occurs in the ___1___ by a process known as ___2___.
- liver
- beta-oxidation
Lipids are used by the body primarily during ______.
low energy activities
True or False: Lipid metabolism yields half the amount of ATP than when a carbohydrate or protein is broken down.
False. Lipid metabolism yields TWICE the amount of ATP than when a carbohydrate or protein is broken down.
A fat molecule is broken down in the mitochondria to form ______.
acetic acid
Acetic acid is further catabolized by the TCA cycle to ___1___ forming some ___2___.
- carbon dioxide
- ATP molecules
______ metabolism only takes place when carbohydrates and fats are unavailable to the body.
Protein
Protein metabolism only takes place when___1___ and ___2___ are unavailable to the body.
- carbohydrates
- fats
Proteins are the ______ for the cells and saved as a last resort.
- building blocks
When proteins must be used to form ATP, the ___1___ is removed from the protein to form ___2___.
- amino group
- ammonia
True or False: Ammonia is harmful to the body and must be converted to a different form.
True
Ammonia is combined with ___1___ in the liver to make ___2___.
- carbon dioxide
- urea
Urea is then excreted from the body in ______.
urine
Glycolysis is the process of breaking down a 6-carbon molecule of glucose into two 3-carbon molecules of pyruvate. This process yields 2 molecules of ATP per molecule of glucose.
