Thermodynamics in biological system.pptx

Thermodynamics in biophysics

1. Biophysics Dr. Qamar Yasmeen (PhD, Biochemistry)

2. Bioenergetics Bioenergetics is the branch of biochemistry that focuses on how cells transform energy, often by producing, storing or consuming adenosine triphosphate (ATP). 

3. Essentials of Thermodynamics Thermodynamics is the study of the relationship between heat, work, and the associated flow of energy Thermodynamics is concerned with storage, transformation and dissipation of energy Cell store energy, they transform it into another form then it is converted to heat to perform unfavorable reactions in the living system

4. Thermodynamics objectives All biological, chemical and physical processes are regulated and enabled by laws of thermodynamics Relationship between heat and work in living/biological system Changes in energy forms in biological reactions For understanding of biochemical reaction taking place in biological systems For measurement of effect of temperature on physico -chemical and biological reactions

5. Thermodynamics concept considering a biological approach Heat produced by humans/animals is due to the slow combustion of food in their bodies. The body of an animal/humans contains internal thermal energy Et , which is the product of the mass and specific heat, and chemical energy Ec stored in the tissue of the body The energy released by the food is balanced by the lost body heat and the work done by the body.

6. Thermodynamic changes are essential for biochemical function and metabolism i.e. anabolism and catabolism

7. Thermodynamic concepts are used to explain: The direction of chemical reactions T he speed of the chemical reactions e.g. enzymatic reactions T he concentration conditions of the equilibrium state T he maximum work performed through a chemical transformation H ow the cell can operate and are able to produce their characteristic compounds and maintain their metabolic processes

8. System

9. Types of system Isolated-No exchange of energy or matter . Example: A thermos is an attempt to isolate a system. An ice chest is another example of an attempt to isolate a system Closed: Only energy allowed to exchange . Examples: A chicken’s egg, Unopened can of soda. Stoppered reaction flask Open: Both energy and matter allowed to exchange. Examples: Humans, Cell , Open reaction flask. Opened can of soda

10. Laws of thermodynamics The laws of thermodynamics are important unifying principles of  biology . These principles govern the chemical processes (metabolism) in all biological organisms. The First Law of Thermodynamics, also known ​as the  law of conservation of energy , states that energy can neither be created nor destroyed. It may change from one form to another, but the  energy in a closed system  remains constant

11. First Law of Thermodynamics in Biological Systems All biological organisms require energy to survive. In a closed system, such as the universe, this energy is not consumed but transformed from one form to another . Cells, for example, perform a number of important processes. These processes require energy. In  photosynthesis , the energy is supplied by the sun. Light energy is absorbed by cells in plant leaves and converted to chemical energy The chemical energy is stored in the form of glucose, which is used to form complex carbohydrates necessary to build plant mass.

12. The energy stored in glucose can also be released through cellular respiration. This process allows plant and animal organisms to access the energy stored in carbohydrates, lipids, and other macromolecules through the production of ATP . This energy is needed to perform cell functions such as DNA replication, mitosis, meiosis, cell movement, endocytosis, exocytosis, and apoptosis.