Patho_Exam1_review.docx

What is epidemiology: study of disease occurrence in human population. To explain the spread of infectious diseases during epidemics and had emerged as a science to study risk factors for multifactorial diseases such as heart diseases and cancer. Types of movement into / out of cell: 1. Diffusion: From areas of higher concentration to areas of lower concentration. passive process by which molecules and other particles in a solution become widely dispersed and reach a uniform concentration because of energy created by their spontaneous kinetic movements. 2. Simple Diffusion: kinetic movement of molecules or ions occurs through a membrane opening or through intermolecular spaces without any interaction with a carrier protein. 3. Facilitated Diffusion: occurs down a concentration gradient; thus, it does not require input of metabolic energy. It requires a transport protein b/c substance such as glucose cannot pass unassisted through cell membrane since they are not lipid soluble and cannot pass through pores. 4. Active Transport: Movement from an area of higher concentration to one of lower concentration, resulting in an equal distribution of permeable substances across the cell membrane. Energy is required to pump the ions “uphill” or against their concentration gradient 5. Primary Active Transport: Direct use of ATP in the transport of solute such as sodium, potassium, calcium, and hydrogen ions (sodium-potassium ATP pump). Na+/K+ pump moves sodium from inside of cell to the extracellular region, where its concentration is about 14 times greater than inside; and the pump returns potassium to inside cell where concentration is about 35 times greater than it s outside. Your text here 1 6. Secondary Active Transport: Utilization of the energy derived from the primary active transport of one solute for the cotransport of a second solute. It harnesses the energy derived from the primary active transport of one substance (sodium), for the cotransport of a second substance 7. Vesicular Transport: mechanism in which materials are transported in membrane bound vesicles. There are two types: endocytosis (materials are moved into a cell in a vesicle formed from the cell membrane – cells engulf materials from the surroundings); and exocytosis (materials are moved out of a cell by fusion of a vesicle with the cell membrane – secretion of intracellular substances into the extracellular spaces – excretes cellular debris) True or false? An action potential is the result of K+ movement into the cell False Rationale: An action potential occurs when Na+ moves into the cell, making it more positive on the inside (depolarization). When K+ leaves the cell, it becomes less positive (more negative) until it returns to resting membrane potential (repolarization). Glycolysis : Aerobic and Anaerobic Cell Metabolism: 1). The glycolytic pathway; 2). Citric acid cycle; 3). Electron transport chain Anaerobic Energy Metabolism: - Occurs in the cytoplasm - Glycolysis breaks glucose, using pyruvate and Nicotinamide Adenine Dinucleotide Hydrogen (NADH) - Produces 2 ATP molecules/ glucose molecule - If oxygen is not present, then pyruvate makes lactic acid - If oxygen is present, then pyruvate lead to aerobic mitochondrial pathway Aerobic Energy Metabolism: is the way the body creates energy through the combustion of carbohydrates, amino acids, and fats in the presence of oxygen - Occurs in the mitochondria - Carbon-containing nutrients + O2 → CO2 + H2O + ATP - Citric acid cycle + electron transport system - Produces 34 to 36 ATP molecules/ glucose molecule True or false? ATP is produced without oxygen True: Rationale: ATP can be produced in the cytosol without oxygen during glycolysis Citric Acid Cycle: By products are 2 carbon dioxide molecules; 1 ATP, and reduced NADH, and FADH2 (Flavin Adenosine Dinucleotide Hydrogen). known as the TCA cycle (tricarboxylic acid cycle) or the Krebs cycle – is a series of chemical reactions used by all aerobic organisms to release stored energy through the oxidation of acetyl-CoA derived from carbohydrates, fats, and proteins, into adenosine triphosphate (ATP). Citric Acid byproduct is: carbon dioxide. 2 ATP are produced in this cycle Under aerobic conditions (presence of oxygen), both pyruvic acid molecules formed by glycolytic pathway enter the mitochondria, where each combines with acetyl-coenzyme A (acetyl-CoA). Through two rounds of the citric acid cycle this generates 6 NADH, 2 FADH2, and 2 ATP total. After oxidative phosphorylation, this is 24 ATP total. As such glucose generates 38 ATP total, a fraction of the ATP is generated from fatty acids. Electron Transport Chain: each glucose molecules of ATP (two from glycolysis and two from the citric acid cycle). The electron transport chain is the final component of aerobic respiration and is the only part of glucose metabolism that uses atmospheric oxygen. Electron transport is a series of redox reactions that resemble a relay race. A total of 32 ATP molecules are generated in electron transport and oxidative phosphorylation Electron Transport Chain byproduct is: water and ATP Electrons are passed rapidly from one component to the next to the endpoint of the chain, where the electrons reduce molecular oxygen, producing water. This requirement for oxygen in the final stages of the chain can be seen in the overall equation for cellular respiration, which requires both glucose and oxygen.