Interest Grabber

Interest Grabber Section 9-1 • Feel the Burn • Do you like to run, bike, or swim? These all are good ways to exercise. When you exercise, your body uses oxygen to get energy from glucose,a six-carbon sugar. 1. How does your body feel at the start of exercise, such as a long, slowrun? How do you feel 1 minute into the run; 10 minutes into the run? 2. What do you think is happening in your cells to cause the changesin how you feel? 3. Think about running as fast as you can for 100 meters. Could youkeep up this pace for a much longer distance? Explain your answer.

Interest Grabber Section 9-1 • Feel the Burn 1. How does your body feel at the start of exercise, such as a long, slowrun? How do you feel 1 minute into the run; 10 minutes into the run? Students may answer that they feel no fatigue at the start of a run; however, after 1 minute and more so after 10 minutes, they are breathing hard, their heart rate has increased significantly, and their muscles may hurt.

Interest Grabber Section 9-1 • Feel the Burn • 2. What do you think is happening in your cells to cause the changesin how you feel? • Students may say that the increase in heart rate and breathing rate are a response that gets extra oxygen to the cells. The pain may be attributed to the cells becoming fatigued.

Interest Grabber Section 9-1 • Feel the Burn 3. Think about running as fast as you can for 100 meters. Could youkeep up this pace for a much longer distance? Explain your answer. • Students may know that very high levels of performance can be sustained only very briefly even among the best of athletes. Students may say that the body runs out of readily available energy, food, or oxygen, or that the body builds up too many waste products in the cells.

Section Outline Section 9-1 • 9–1 Chemical Pathways A. Chemical Energy and Food B. Overview of Cellular Respiration C. Glycolysis 1. ATP Production 2. NADH Production D. Fermentation 1. Alcoholic Fermentation 2. Lactic Acid Fermentation

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 • __________________________. our bodies form new cells.

3811 1 gram of sugar releases _______ calories of heat energy. • A calorie is the amount of energy needed to raise the temperature of ______________ • ___________________. 1 gram of water 1 degree Celsius.

When we consume food, our bodies breakdown food__________________________________. to release energy and build new cells • The breakdown of food begins with the process called _______________________. glycolysis

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

Glycolysis comes from the Greek word glukus meaning ____________ and the Latin word lysis means ______________________. • “dissolving or decomposing” “sweet”

1st step of glycolysis • 2 ATPS are needed to activate glucose. 2nd step Splitting of Glucose • Glucose is split into 2 3-carbon compounds. See animation of glycolysis

3rd Step of Glycolysis – Energy Generation • 2 NAD+ are reduced. At the same time, a phosphate group is added to each 3 carbon molecule. • 2 ATPs replace those required for activation. • A net of 2 ATPs per glucose are produced in glycolysis.

Glycolysis is the process in which one molecule of glucose is broken in half producing two molecules of ______________________. pyruvic acid / pyruvate Produces 4 ATP molecules. 2 ATP molecules were used in producing the 4 ATP molecules Glycolysis Net gain of 2 ATP overall

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

HIGH ENERGY ELECTRONS require a special carrier, too • ____________ is one • of the carriers that • cells use to transport • high energy electrons. NAD+ ________ + _____ + _____ → ____________ NAD+ 2 e- H+ _______= nicotinamide adenine dinucleotide NAD+

Figure 9–2 Cellular Respiration: An Overview Section 9-1 Mitochondrion Electrons carried in NADH Electrons carried in NADH and FADH2 Pyruvic acid Glucose Electron Transport Chain Krebs Cycle Glycolysis Mitochondrion Cytoplasm

Figure 9–3 Glycolysis Section 9-1 Glucose 2 Pyruvic acid To the electron transport chain

it is needed in following events small • 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 ______________________________. just a few milliseconds not require oxygen ATP production stops

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 Lactic Acid Fermentation NAD+ anaerobic

Alcoholic Fermentation Pyruvic acid + NADH → alcohol + carbon dioxide + NAD+ 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.

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

Lactic Acid Fermentation • Pryuvic acid + NADH → lactic acid + NAD+ • 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.

Chemical Pathways Section 9-1 Glucose Krebs cycle Electrontransport Glycolysis Alcohol or lactic acid Fermentation (without oxygen)

SOUTH DAKOTA SCIENCE STANDARDS • Chapter 9 – Cellular Respiration: • The students will be able to • describe the process of cellular respiration (9-12.L.1.1) • identify the components of glycolysis (9-12.L.1.1) • compare the processes of alcoholic and pyruvic acid fermentations (9-12.L.1.1) • analyze chemical reaction and chemical processes involved in the Krebs Cycle (9-12.L.1.1) • explain the mitochondrial role in the ATP-ADP cycle (9-12.L.1.1) • Assess the role of enzymes in plant reactions (LAB)

SOUTH DAKOTA CORE SCIENCE STANDARDS LIFE SCIENCE:Indicator 1: Understand the fundamental structures, functions, classifications, and mechanisms found in living things • 9-12.L.1.1. Students are able to relate cellular functions and processes to specialized structures within cells. • Photosynthesis and respiration • ATP-ADP energy cycle Role of enzymes Mitochondria Chloroplasts

Core High School Life SciencePerformance Descriptors

SOUTH DAKOTA ADVANCED SCIENCE STANDARDS LIFE SCIENCE:Indicator 1: Understand the fundamental structures, functions, classifications, and mechanisms found in living things. • 9-12.L.1.1A. Students are able to explain the physical and chemical processes of photosynthesis and cell respiration and their importance to plant and animal life. (SYNTHESIS) • Examples: Krebs Cycle

Interest Grabber