Biology Questions and Answers February 28, 2020

1. Glucose will react with oxygen in a laboratory setting using a combustion chamber. The reaction is exergonic, with the release of a large amount of energy in the form of heat and the production of carbon dioxide and water according to the following chemical equation: C 6 H 12 O 6 + 6O 2 ? 6CO 2 + 6H 2 O ? ? ? G = ?686 kcal/mol Glucose can also

Change in free energy, AG (in kcalmol) 100 Glucose 100 200 300 GLYCOLYSIS ATP ATP NADH ATP ATP Pyruvate NADH Acetyl CoA 400 In each of these 500 600 700 PYRUVATE PROCESSING AND CITRIC ACID CYCLE drops, energy is transferred to energystoring molecules ATP, NADH, and FADH NADH NADH ATP FADH NADH Oxaloacetate

2. A biologist examines the organelles present in the root cells, stem cells, and leaf cells of a green plant. She finds a high density of mitochondria and no chloroplasts in the root cells, but an abundance of mitochondria and an abundance of chloroplasts in the stem and leaf cells. a. Explain the fact that all of the cells in the plant contain

3. Compare the mechanisms and structural features of aerobic and anaerobic respiration. (4 points)

4. Cellular respiration involves many different subcellular structures that carry out specialized processes that work together to oxidize glucose, forming carbon dioxide and water and releasing energy. a. Explain how the chemical breakdown of glucose results in the production of a hydrogen ion concentration gradient across the mitochondrial

Protons are pumped across this membrane as electrons flow through the respiratory chain. High H Low H H Outer mitochondrial membrane Inner mitochondrial membrane Intermembrane space Matrix

5. The figure below illustrates the effect of insulin on glucose uptake. Explain how insulin is involved in the regulation of cellular respiration. (3 points)

Effect of Insulin on Glucose Uptake Insulin 1 Insulin receptor 55 SE OS CYTOPLASM (2 55 Se es P P Glucose (5) GLUT4 GLUT4 containing vesicle