Metabolism Flashcards
What is Metabolism?
- A network of multi-step pathways/ reactions via enzymes.
- A network of metabolic/ biochemical reactions
- Carried out in living cells in a well organized, integrated and regulated manner
- Involves interconversions of chemical compounds in the body
- Metabolic precursors are transformed to end products via specific intermediates
What are the types of Metabolism?
- Various types of Metabolism:
1. Carbohydrates
2. Lipids
3. Proteins
4. Nucleoproteins
What is he importance of Metabolism?
Metabolism is the sum of the chemical changes
(Catabolic + Anabolic = Metabolic) that convert:
- Nutrients into energy
- Chemically complex substances of cells into simpler forms
- Chemically simple substances into functional complex biomolecules
Therefore, normal metabolism is vital for health, growth, development, repair, survival and reproduction.
What is the Role of Enzymes in Metabolism?
- Enzymes along with Coenzymes biocatalyze specific metabolic reactions
- Thus enzymes are “Functional units of Metabolism”
- Enzyme reactions are organized in discreet pathways
What is the Role of Hormones in Metabolism?
- Hormones are chemical messengers of the human body. They are regulators of enzyme activity. (ie they stimulate or inhibit enzyme activity)
What is a Metabolite?
- A substrate or a reactant undergoing a biochemical/ metabolic reaction.
What is a Metabolic Reaction?
- A biochemical reaction where a metabolite is specifically reacted by an enzymes and coenzyme to give a product
A ——————-> B
E-Co
What are Types of Metabolic Reactions?
- Reversible Reactions
- same enzyme is needed for forward and reverse
reactions
- Not regulatory steps - Irreversible Reactions
- different set of enzyme required
- Non equilibrium rxns
- Regulatory steps
What are the types of Biochemical Reactions?
- Oxidation/ dehydrogenation/ Hydroxylation
- Reduction
- Hydrolytic
- Carboxylation
- Decarboxylation
- Phosphorylation
- Dephosphorylation
- Amination
- Deamination
- Isomerization
- Hydration
- Dehydration
What is a Metabolic Pathway?
- A series of well defined and significant biochemical reactions followed one after another giving intermediate products and final end product of the pathway.
A —-> B —-> C —-> D —-> E
A - Precursor
B,C,D - Intermediates
E - End Product
What are the Types of Pathways?
- Linear Pathway
- from Precursor (substrate) to End Product
- Series of independent enzymes
- Products substituted for next rxn
- eg. Glycolysis - Cyclic Pathway
- the end products become the precursors of the next cycle
- in a circle
- intermediates are regenerated every turn
- eg. Citric Acid/ Krebs Cycle
3 Spiral Pathway
- every cycle an element gets added on to the product
- same set of enzymes are used repeatedly
- polymerization rxns
- eg. Fatty Acid Synthesis
What is Compartmentalization of Metabolic Pathways and What is its Importance?
Compartmentalization of Metabolic Pathways is when various metabolic pathways occur in various parts of the cell. eg Glycolysis occurs in the cytosol (cytoplasm) and the Krebs cycle occurs in the matrix of the mitochondria
- Compartmentalization is vital as it permits integration and regulation of metabolism
What are the types of Metabolic Pathways?
- Catabolic- Degradative/ Energy Generating/ ATP producing/ Exothermic Pathways
- Catabolic pathways involve oxidative rxns producing reducing equivalents- NADH + H+ and FADH2 - Anabolic- Synthetic/ Energy Utilizing/ ATP using/ Endothermic Pathways
- Anabolic pathways reductive rxns producing oxidizing equivalents- NAD+ and FAD+
What are Amphibolic Pathways?
- Pathways serve both in Catabolism and Anabolism
- Occurs at the crossroads of metabolism
- Links between anabolic and and catabolic pathways
What is Regulation of Metabolic Pathways?
- Regulation means stimulation and inhibition of pathways as per cellular need
- Hormones regulate the metabolic pathways
- Metabolic pathways are regulated to allow the organism to respond to changing conditions
- Every metabolic pathways has its specific regulatory enzymes/ Key enzymes
- Hormones regulate by either stimulating / inhibiting the regulatory key enzymes of the pathway
