Chemical Pathways Chapter 9 Section 1 Name:___________________________________

Each of our bodies has a different way to let us know when we are hungry. Food serves as a source of raw materials from which __________________________.

A calorie is the amount of energy needed to raise the temperature of ______________ ___________________. 1 gram of sugar releases _______ calories of heat energy.

The breakdown of food begins with the process called _______________________. When we consume food, our bodies breakdown food__________________________________.

Video 2 Click the image to play the video segment. Video 2 Glycolysis Video Chapter 9B.mpg

Glycolysis comes from the Greek word glukus meaning ____________ and the Latin word lysis means ______________________.

1 st step of glycolysis See animation of glycolysis 2 nd step Splitting of Glucose

3 rd Step of Glycolysis – Energy Generation.

Glycolysis is the process in which one molecule of glucose is broken in half producing two molecules of ______________________.

GLYCOLYSIS Happens in ______________ of cell Four electrons are passed to an electron carrier called _______________ NAD + accepts electrons to make __________ _______ is nicotinamide adenine dinucleotide.

HIGH ENERGY ELECTRONS require a special carrier, too ____________ is one of the carriers that cells use to transport high energy electrons. ________ + _____ + _____ → ____________ _______= nicotinamide adenine dinucleotide

Go to Section: Glucose Glycolysis Cytoplasm Pyruvic acid Electrons carried in NADH Krebs Cycle Electrons carried in NADH and FADH 2 Electron Transport Chain Mitochondrion Figure 9–2 Cellular Respiration: An Overview Mitochondrion Section 9-1

Go to Section: Glucose To the electron transport chain Figure 9–3 Glycolysis Section Pyruvic acid

NADH holds the electron until ___________________ ______________________. The energy yield from glycolysis is __________. The process is so fast that cells can produce thousands of ATP molecules in __________________. Besides speed, glycolysis does _________________. Without NAD+, the cell cannot keep glycolysis going, and ______________________________.

Following Glycolysis when oxygen is absent: If oxygen is not present, a cell begins with glycolysis and continues with a different pathway called fermentation. There are two types of fermentation: ________________ During fermentation NADH converts to _________. This is an ______________ process.

Alcoholic Fermentation Used in bread production (leavened bread) uses yeast to raise the bread. Yeast uses sugar and gives off carbon dioxide. The alcohol generated cooks out of the bread when baking.

Go to Section: Glucose Pyruvic acid Lactic acid Figure 9–4 Lactic Acid Fermentation Section 9-1

Lactic Acid Fermentation When you exercise vigorously by running/swimming, your muscle cells need oxygen. When there is not enough oxygen, your body can’t produce all the ATP that it needs. Your muscles begin to generate ATP by lactic acid fermentation. This buildup causes a painful burning sensation. This is why muscles feel sore or you get a side ache. You need to breathe to reverse the lactic acid fermentation to cellular respiration.

Lactic Acid Fermentation Unicellular organisms produce lactic acid as a waste product during fermentation. Prokaryotes (good bacteria) are used in the production of a wide variety of foods and beverages such as cheese, yogurt, buttermilk, sour cream, pickles, sauerkraut, and kimchi. All of the above foods are produced using lactic acid fermentation.

Go to Section: Glucose Glycolysis Krebs cycle Electron transport Fermentation (without oxygen) Alcohol or lactic acid Chemical Pathways Section 9-1