February 14, 2014

Pick up the handout and schedulefrom the front

1st Law of ThermodynamicsThe energy of the universe isconstant. Energy can be transformed & transferred, but it cannot be created or destroyed.

2nd Law of ThermodynamicsEvery energy transfer ortransformation makes the universe more disordered. In other words,every energy transfer or transformation increases theentropy of the universe

Based on free energy changes, reactions can be classified as exergonic (energy outward) or endergonic (energy inward). An exergonic reaction proceeds with a net release of free energy. They occur spontaneously. An endergonic reaction is one that absorbs free energy from its surrounds; the energy is stored in the product; they are nonspontaneous.

Energy Transfer

25 kJHere is a food pyramid that begins with producers and ends with tertiary consumers. If the producer level contains 25,000 kJ of energy and this pyramid follows the 10% rule, then how much energy gets transmitted to the tertiary consumers?All of the questions are printed at the back of your handout

42 g/m2Carbon Flow in a Grassland Ecosystem

How much carbon (g/m2) is released into the atmosphere as a result of the metabolic activity of the herbivores?

G = H TSG = Free EnergyH = EnthalpyS = EntropyT = Temperature in Kelvin represents change in value over time

An experiment determined that when a protein unfolds to its denatured (D) state from the original folded (F) state, the change in Enthalpy is H = H(D) H(F) = 56,000 joules/mol. Also the change in Entropy is S = S(D) S(F) = 178 joules/mol. At a temperature of 20C, calculate the change in Free Energy G, in j/mol, when the protein unfolds from its folded state. The correct answer is 3,846 joules/mol.G = H TSG = (56,000 joules/mol) 293 K (178 joules /mol)G = 56,000 joules/mol 52,154 joules/mol = 3,846 joules/mol

A + B + energy ABThere are many types of biochemical reactions taking place in any living system. Which of the followingbest characterizes the reaction represented above?A) CatabolismB) Oxidation-reductionC) Exergonic reactionD) Endergonic reaction

Energy Transfer

6CO2 + 6H20 + energy C6H12O6 + 6O2C6H12O6 + 6O26CO2 + 6H20 + energyWhen you compare the formula for photosynthesis with cellular respiration, which is exergonic, which is endergonic? They are both oxidation/reduction reactions.

6CO2 + 6H20 + energy C6H12O6 + 6O2C6H12O6 + 6O26CO2 + 6H20 + energy

CELLULAR RESPIRATION- AN OVERVIEW

Where is the energy transfer?

Where is the energy transfer?

A molecule that is phosphorylated:

Has an increased chemical reactivity; it is primed to do cellular workHas a decreased chemical reactivity; it is less likely to provide energy for cellular workHas been oxidized as a result of a redox reaction involving the gain of inorganic phosphateHas been reduced as a result of a redox reaction involving the loss of an inorganic phosphate

Which of the following statements describes the results of this reaction?

C6H12O6 + 6O2 6CO2 + 6H20 + energy

a. C6H12O6 is oxidized and O2 is reducedb. O2 is oxidized and H20 is reducedc. CO2 is reduced and O2 is oxidizedd. C6H12O6 is reduced and CO2 is oxidized

Starting with one molecule of glucose, thenet products of glycolysis are:

2 NAD+, 2 H+, 2 pyruvate, 2 ATP and 2 H202 NADH, 2 H+, 2 pyruvate, 2 ATP, and 2 H202 FADH2, 2 pyruvate, 4 ATP and 2 H206 CO2, 6 H20, 2 ATP and 2 pyruvate

Where is the energy transfer?

Where is the energy transfer?

Where is the energy transfer?

Where is the energy transfer?

Where is the energy transfer?

Where is the energy transfer?

Where is the energy transfer?There is compartmentalization within themitochondrion. What purpose does it serve?

How is a concentration gradient important inthe process shown here?

What is the significance of the inner membranebeing folded?

Add it all up-

This is probably26-28 ATPThis number isProbably lower

The oxygen consumed during cellular respiration is involved directly in which process or event?GlycolysisAccepting electrons at the end of the end of the electron transport chainc.The citric acid cycled.The oxidation of pyruvate to acetyl CoA

Organic molecules besides carbohydrates can transfer energy

Which process in eukaryotic cells will proceed normally whether O2 is present or not and therefore probably evolved first?Electron transportGlycolysisThe citric acid cycleOxidative phosphorylation

You have a friend who lost 7 kg (about 15 pounds) of fat on a low carb diet. How did the fat leave her body?

It was released as carbon dioxide and waterb. Chemical energy was converted to heat and releasedc. It was converted to ATP, which weighs less than fatd. It was converted to urine and eliminated from the body

Photosynthesis!!!

Relate the structure to the function-

We have compartmentalization again

Lots of surface area

Relate structure and function-

-At the organ level

-At the tissue level

-At the cellular level

-At the molecular level

Photosynthesis- An Overview

Where is the energy transfer?

Where is the energy transfer?

Where is the energy transfer?

Where is the energy transfer?

C3 PlantsWhere is the energy transfer?

Use these terms to summarize the Calvin Cycle.

Carbon dioxide (CO2)Ribulose biphosphate (RuBP)Rubisco 3-phosphoglycerateATPNADPHGlyceraldehyde-3-phosphate (G3P)Glucose

In the Calvin Cycle, CO2 is attached to a molecule of RUBP. This is catalyzed by the enzyme rubisco. The six carbon product splits, forming two molecules of 3-phosphoglycerate. 3-phosphyglycerate receives a phosphate from ATP and electrons from NADPH forming a molecule of G3P. Two molecules of G3P can combine to form a molecule of glucose.

Where is the energy transfer?

Photosynthetic Adaptations

Alternate mode of carbonfixation that forms a 4-carbon compound as its first product.A way to cut down on photorespiration.Sugarcane, corn, members ofthe grass family (at least 1000 plants)

CAM PhotosynthesisEvolved in succulent plants, many cacti, pineapples &other plants. Open stomata during night, close during day

Compare and contrast the energy transfer in mitochondria & chloroplasts

Energy Flow in a Hardwood ForestWhat percentage of the biomass in the forest community is tied up in theGrass layer which has a question mark?

The EndThe End

This is very simple, there are a lot of other questions you could ask about this if time permits. For example- according to the 1st lawq of thermodynamics, energy cannot be destroyed. What happened to the energy?This applies to the conservation of matter, but I think it fits here. This is part of the carbon cycle which we need to review and also relates to cellular respiration. These 2 problems (this one and the energy pyramid) are so simple, that sometimes students cant work them because they think there is a trick.This is the only slide on enzymes, elaborate as much as you feel necessary.Important part is the energy transferTo save time and condense the ppt, I took out the other slides on fermentation.I think its important to mention this, especially to show where nitrogenous wastes come from.Emphasize, this is part of the carbon cycle