Cellular respiration-real life

• So far we’ve looked at glucose entering into cellular respiration... But what about proteins, carbs, fats & lipids? They give us energy too right?

• We need to eat a balanced diet-fats/lipids: essential for use of fat soluble

vitamins in our food to be used... – Proteins help build muscle, etc.

• These enter the metabolic process at different stages.

Varied diet and metabolic pathways

Nutrients enter the metabolic process at different stages.

• Proteins Amino acids pyruvate or krebs intermediate

• Carbos sugars glucose Glycerol G3P (in glycolysis)• Fats Fatty acids acetyl CoA

deamination

HTTP://WWW.YOUTUBE.COM/WATCH?V=PQMSJSME780&FEATURE=RELATED

http://www.youtube.com/watch?v=00jbG_cfGuQ cell resp crash courseVideo on breakdown during aerobic exercise

Anaerobic respiration

Photoautrophheterotroph

chemoautotrophwe all do it!

Cellular Respiration: The Big Picture

Cellular Respiration: The Details

Related Pathways

Fermentation occurs in the ABSENCE OF OXYGEN.

LACTIC ACID FERMENTATION

or

ALCOHOLIC FERMENTATION.

Aerobic respiration

• Yields 36 ATP/glucose

• Produces CO2 and water

Fermentation

• Yields 2 ATP/glucose

• Produces ethanol or lactic acid

Anaerobic Pathways

• When oxygen is not available• Eukaryotes still carry out glycolysis by

transferring the H atoms in NADH to pyruvate • The NAD+ molecules formed allow glycolysis

to continue

Ethanol (Alcohol) Fermentation

Occurs in yeast cells and is used in wine, beer, and bread making

Ethanol (Alcohol) Fermentation

• A molecule of CO2 is removed from pyruvate, forming a molecule of acetaldehyde

• The acetaldehyde is converted to ethanol by attaching H from NADH

• FINAL PRODUCTS: ATP, CO2, ethanol

A particular organism releases carbon dioxide and alcohol as its end products. The organism is

most likely which of the following?

a. an animalb. an algac. a green plantd. a yeaste. a virus

d. a yeast

Anaerobic and aerobic respiration are similar in all but one of the following ways. Which one is the

exception?

A) NAD+ is reducedB) carbon dioxide is a productC) ADP is combined with inorganic phosphate to form ATPD) acetaldehyde is converted into ethanolE) both can release energy from glucose

D) acetaldehyde is converted into ethanol

Lactate (lactic acid) fermentation

• Occurs in animal muscle cells during strenuous exercise• FINAL PRODUCTS: ATP, lactate

What happens to lactic acid after it is formed in a muscle cell?

• Lactic acid travels in the bloodstream to the liver, where it is oxidized back to pyruvate, which then goes through the Krebs cycle and oxidative phosphorylation.

• The presence of lactic acid in the muscle tissues leads to stiffness, soreness, and fatigue.

Oxygen debt

• Oxygen debt refers to the extra oxygen required by the liver to oxidize lactic acid to CO2 and water (through the aerobic pathway)

• Panting “pays” for the oxygen debt

During active exercise, the supply of oxygen becomes inadequate for the level of activity you are attempting to

maintain. How do the catabolic reactions of the cell continue?

• Glycolysis continues to supply small amount of ATP, and the pyruvate that normally would continue on the Krebs cycle as acetyl-CoA is instead converted to lactate to regenerate NAD+ to allow glycolysis to continue.

VO2 max and the Lactate Threshold

• The maximum oxygen uptake (VO2 max) is the maximum volume of oxygen that the cells of the body can remove from the bloodstream in one minute per kg of body mass while the body experiences max. exertion.

• The lactate threshold (LT) is the value of exercise intensity at which blood lactate concentration begins to increase sharply.

Overview of Cellular Respiration which occurs in

STAGE 1: GLYCOLYSIS

STAGE 2: TWO MAIN PATHWAYS,

DEPENDING ON WHETHER THERE IS OXYGEN IN THE

CELL.

Aerobic Respiration produces nearly 20 times

as much ATP as is produced by Glycolysis

alone.

Anaerobic respiration

Read and make notes134-137 and answer #1-8 pg 137