2 Energy and Thermodynamics

7/28/2019 2 Energy and Thermodynamics

1/39

Topics

1. Introduction

2.Energy and thermodynamics

3.Feeding and ingestion

4. Ionic gradient, electrical potential

5.Electrical signals and neurons

6.Locomotion, muscle and skeleton

7.Heat production and body temperature


2/39


3/39

Reading assignment

Energy and life

http://hyperphysics.phy-astr.gsu.edu/hbase/biology/enercyc.html

Thermodynamics

http://www.estrellamountain.edu/faculty/farabee/biobk/BioBookEner1.html

Biological system and thermodynamics

http://www.bio.net/bionet/mm/neur-sci/1995-July/019223.html

Obesity

http://www.nlm.nih.gov/medlineplus/obesity.html

Food label and calorie information

http://www.nutritiondata.com/

Which exercise burns more calorie?

http://www.healthcentral.com/diet-exercise/quizzes-251185.html
http://hyperphysics.phy-astr.gsu.edu/hbase/biology/enercyc.htmlhttp://www.estrellamountain.edu/faculty/farabee/biobk/BioBookEner1.htmlhttp://www.bio.net/bionet/mm/neur-sci/1995-July/019223.htmlhttp://www.nlm.nih.gov/medlineplus/obesity.htmlhttp://www.nutritiondata.com/http://www.healthcentral.com/diet-exercise/quizzes-251185.htmlhttp://www.healthcentral.com/diet-exercise/quizzes-251185.htmlhttp://www.healthcentral.com/diet-exercise/quizzes-251185.htmlhttp://www.healthcentral.com/diet-exercise/quizzes-251185.htmlhttp://www.healthcentral.com/diet-exercise/quizzes-251185.htmlhttp://www.healthcentral.com/diet-exercise/quizzes-251185.htmlhttp://www.nutritiondata.com/http://www.nlm.nih.gov/medlineplus/obesity.htmlhttp://www.bio.net/bionet/mm/neur-sci/1995-July/019223.htmlhttp://www.bio.net/bionet/mm/neur-sci/1995-July/019223.htmlhttp://www.bio.net/bionet/mm/neur-sci/1995-July/019223.htmlhttp://www.bio.net/bionet/mm/neur-sci/1995-July/019223.htmlhttp://www.bio.net/bionet/mm/neur-sci/1995-July/019223.htmlhttp://www.estrellamountain.edu/faculty/farabee/biobk/BioBookEner1.htmlhttp://hyperphysics.phy-astr.gsu.edu/hbase/biology/enercyc.htmlhttp://hyperphysics.phy-astr.gsu.edu/hbase/biology/enercyc.htmlhttp://hyperphysics.phy-astr.gsu.edu/hbase/biology/enercyc.html


4/39

What is physiology?

Physiology deals with the (1) processes,

(2) activities and (3) phenomenaincidental

to and characteristics oflife.


5/39

What is live?

What is death?

Why do you need a supply

of energy to be alive?


6/39

What are living organisms made of?atoms

molecules

macromolecular complex

elementary cellular structures

organelles

cellstissues

organ systems

animal

(Chemistry)

(Biochemistry)macromolecules

(Cell Biology)

(Genetics)(Histology)

(Physiology)


7/39

Energyis necessary to maintain

structure, but structure is in turn

necessary to utilize the energy.


8/39

Laws of Thermodynamics

1. The amount ofenergy present in this

Universe is constant.

2. There is alwaysa certain amount ofenergy which changes into a lower quality

form such as heat and becomes less

available to do work.

(Concept of entropy)


9/39


10/39

Different forms of energyGravitational energy

Energy of rotationEnergy of orbital motion

Energy of nuclear fission

Energy of nuclear fusionSolar energy

Sound energy

Electrical energy

Energy of chemical reaction

Chemical potential energy

Heat

Cosmic radiation


11/39

Laws of Thermodynamics

1. The amount ofenergy present in this

Universe is constant.

2. There is alwaysa certain amount ofenergy which changes into a lower quality

form such as heat and becomes less

available to do work.

(Concept of entropy)


12/39

Both 1st and 2nd Laws ofThermodynamics refer to observations

made on the Universe and not only the

system that we are interested in.

Universe= System +Surrounding


13/39

SURROUNDING

SYSTEM


14/39

Living systems would appear defy theSecond Law of Thermodynamics because oftheir high degree of maintained order.

How do you reconcile the low entropy of anorganism with this fundamental physical law?

Can the 2nd law of thermodynamics beapplied here?

egg

Highly-ordered

organism


15/39

Ingestion of food by animal increases the entropy of

the food molecules by breaking them down intosmaller molecules of lower free energy content.

The free energy liberated is utilized by animal cells

to drive energy-requiring reactions.

H2OCO2

Nitrogenous

waste

H2O

H2O


16/39

Initial State

Final State


17/39

In relationship to chemical reactions, Gibbs Free

Energy(G)defines if the reaction would go

spontaneously from the initial state to the final state.

where H = change in enthalpy (heat content)

G = H - T S

G = H +(- T S)

S = change in entropy (energy that is highly

dispersed and not available to do work)

Reactions would go spontaneously in the direction of

achieving a final state of lower internal energy in the

system.


18/39

Initial State

Final State


19/39


20/39

Whats the meaning ofG?

-G= the maximum amount of energytheoretically available for the system to dobiological useful work on its surrounding

when the system goes from initial state tothe final state if the process is reversible.

= Exergonic

G = Gfinal - Ginitial


21/39

+ G= the amount of energytheoreticallythesurrounding has to supply to the system so

that it can go from the initial state to the final

state

= Endergonic

G = Gfinal - Ginitial


22/39

G = 0 = equilibrium

A + B C + D

Keq = [C] [D]

[A] [B]

IfKeqis very big, e.g. 106, we basically still assumethere is some A and some B left.

Thermodynamics deals with collections of matter.

It does not apply to several molecules. As such itsanalyses depend a lot on statistical probability.


23/39

Under what condition will an

endergonic reaction proceed?


24/39


25/39

ADP

C6H12O6 + 6O2COUPLE

ATP

6CO2 + 6H2O

G = +7000 cal / mole

G = -420,000cal / mole

G = -686,000cal / mole


26/39


27/39

Biological TranducersTransformation Transducers

Chemical electrical

mechanicalChemical

Chemical osmotic

Light

Sound

electrical

electrical

Light chemical

Brain, nerve

Nose, tongue

Muscle

Kidney

Eye

Ear

Plant


28/39

What is unique to living organisms?

The essential feature of living organisms is

their ability to capture, transformand

storevarious forms of energy accordingto the specific instructions of their

individual genetic materials.


29/39


30/39


31/39


32/39

Photosynthesis

(leaf)CO2 + H2O O2 + C6H12O6

PLANTS

Solar

energy

Respiration (mitochonddria)

ATP

Mechanical Transport Assembly

contractionof solute of biomolecules

ADP ADP ADP

Protein

FatsCarbohydrate


33/39

Solar energy/light

Chemical potential energy e.g. Na+ or K+ gradient

Chemical energy, ATP

Chemical energy, e.g. carbohydrate

Electrical energy, e.g. membrane potential

Heat

Heat

Heat

Heat

Chemical energy, ATP


34/39

End


35/39

Teaching is transmission of knowledge

to students

Instruction Paradigm

Versus

Teaching is facilitation of students

learning

Learning Paradigm


36/39

Be an Active Listener

People speak at 100 to 175 words per minute,but they can listen intelligently at up to 300 words

per minute.

Mind-driftthinking about other things whilelistening to someone.

Listen with a purpose (gain info, obtain

directions, understand others, solve problems,

share interests, show support)

Try repeating words mentally as they say it

control mind drift.


37/39


38/39

Topics

1. Introduction

2.Energy and thermodynamics

3.Feeding and ingestion4. Ionic gradient, electrical potential

5.Electrical signals and neurons

6.Locomotion, muscle and skeleton

7.Heat production and body temperature


39/39

Documents

2 Energy and Thermodynamics