Physiology: Digestion, Absorption & Metabolism of Carbohydrates, Lipids & Proteins- Student Objectives (not done) Flashcards
List the basic components of a simple homeostatic control system. (3)
- sensor
- method to conduct and transmit the electrical/chemical message
- effector
Explain why organisms must expend energy continuously.
Because exerting homeostatic control requires energy.
List molecular sources of energy used by animals.
- glucose
- volatile fatty acid
- fatty acids
- amino acids
(5. ketones)
What is a biochemical pathway?
A sequence of chemical reactions allowing for orderly transformation from one molecule to another that allows for utilization of the sources of energy.
List the biochemical pathways which are utilized to obtain energy from carbohydrate, lipid, and protein.
Glycolysis Krebs cycle Beta-oxidation Deamination and transamination (Gluconeogenesis)
What is glycolysis?
Process by which glucose is oxidized in the absence of oxygen and then converted into 2 pyruvate molecules and the only way anaerobic cells can generate ATP.
What is the Krebs Cycle (Citric Acid, TCA)?
A process by which acetyl CoA molecule derived from pyruvate, volatile fatty acids and amino acids are condensed with oxaloacetate to form citrate molecules that are then oxidized in the presence of oxygen.
What is Beta-Oxidation?
A process by which fatty acids are converted to acetyl-CoA molecules in the mitochondria. Also produces reduced cofactors which are oxidized in the ETC in the presence of oxygen.
What is deamination & transamination?
A process by which an amine group is removed from amino acids producing acetyl CoA molecules or molecular intermediates of the TCA cycle which can be oxidized in the presence of O2.
What is gluconeogenesis?
A pathway by which non-carbohydrate precursors are converted into glucose.
Define anabolism.
The manufacture of large & complex molecules/structures which is powered by catabolism.
Define catabolism.
The breakdown of large molecules into smaller ones that releases the energy required to perform the work of anabolic reactions.
Define metabolism.
The sum of all anabolic and catabolic reactions in an organism and the reactions involved in the disposal of waste products of anabolic and catabolic reactions.
Define digestion.
.
Define absorption.
A process involved in the transport of molecules from the lumen of the GI tract through the epithelium of the GI tract and eventually into the bloodstream.
Define oxidation.
A loss of electrons accompanied by the release of energy.
Define reduction.
A gain of electrons.
Define fermentation.
Oxygen absent or in short supply causes an organic molecule to serve as the ultimate electron acceptor–only occurs in carbohydrates and only through the glycolytic pathway.
Define aerobic respiration.
Oxidation in the presence of oxygen occurring in all cells which have mitochondria (O2 is reduced in mitochondria).
Define anaerobic respiration.
Performed in the cytoplasm by cells lacking O2 or mitochondria.
Explain the importance of glycolysis under anaerobic conditions.
.
Explain the significance of elevated plasma lactate.
Increased anaerobic process (glycolysis).
Increased lack of oxygen.
State the major form in which carbohydrate is ingested by animals.
.
List the different carbohydrate molecules ingested by animals and state whether they are found in plants, animals, or both.
.
Describe the basic molecular difference between carbohydrate polymers that are utilized for energy storage and those that are utilized for structural purposes.
.
Define homeostasis.
The ability of organisms to maintain their internal environment regardless of changes to the external environment.
