glucose, faKy acids, amino acids

-­‐ the breaking down of organic macromolecules (glucose, fa8y acids, amino acids, etc.) in the presence of oxygen to produce ATP (occurs in mitochondria) (glucose)
Burning Calories and Cellular RespiraDon •  “Burning calories” refers to the process of using organic molecules from food to make ATP in cellular respiraDon •  Metabolic rate is the rate at which your body turns nutrients into usable energy (ATP) •  Metabolic rate is increased by exercise and adding muscle mass What is ATP? •  Stands for adenosine tri-­‐
phosphate •  Produced in mitochondria during cellular respiraDon •  ATP is used to power any process in the cell that requires energy Nature.com ATP Hydrolysis ATP and PhosphorylaDon •  PhosphorylaDon is the process of adding a phosphate group to an organic molecule (oNen a protein) to acDvate or inacDvate the molecule. •  ATP is oNen a source of phosphate groups for these reacDons h8p://www.nature.com/scitable/topicpage/protein-­‐
funcDon-­‐14123348 Proteins can become acDve through removal or addiDon of a phosphate group (kinases are enzymes that add phosphate groups •  Energy from food is measured in Calories •  Energy is stored in the bonds (electrons) of the food molecules •  Electrons from these macromolecules are used in the cell to produce ATP 3 Steps of Cellular Respira4on (each produces some ATP) 1)  Glycolysis -­‐ spliYng of glucose (2 ATP) (anaerobic -­‐ no O2 needed) 2) Citric Acid (Krebs) cycle (2 ATP) (aerobic -­‐ O2 needed) 3) Electron transport chain (32-­‐34 ATP) (aerobic) *steps 2 and 3 happen inside mitochondria *step 1 happens in the cytoplasm outside the mitochondria Electron Carriers •  A molecule capable of accepDng one or more electrons from another molecule •  Carriers donate these electrons to another molecule inside the mitochondria to aid in ATP producDon •  NAD+ and FADH are e-­‐ carriers NAD+ picks up e-­‐ from glucose and transports them to the e-­‐ transport chain chemistry.ewu.edu Glycolysis Summary •  Glucose is broken down by enzymes in the cytoplasm (into 2 molecules of pyruvic acid) •  A net gain of 2 ATP •  Electron carrier NADH is produced Glucose 2 ATP 2 pyruvic acid molecules Glycolysis (metabolic pathway) tutorvista.com What happens without oxygen? •  Krebs cycle and electron transport chain (ETC) cannot occur •  Glycolysis is followed by fermenta2on •  There are two types of fermentaDon: alcoholic and lac2c acid See diagram O2
Glucose
Glycolysis Krebs cycle and Electron transport chain (inside mitochondria) Pyruvic Acid
No O2
LacDc Acid FermentaDon •  Happens in muscle of humans and other animals in the absence of oxygen ( anaerobic) •  LacDc acid and CO2 are produced •  Does not produce ATP, but it does allow glycolysis to occur again and again to produce ATP for a limited Dme •  Produces burning feeling during exercise Alcoholic FermentaDon •  Happens in microorganisms (yeast and bacteria) in the absence of oxygen (anaerobic) •  Alcohol and CO2 are produced •  Used in the beer and wine industry O2
Glucose
Glycolysis Krebs cycle and Electron transport chain (inside mitochondria) Pyruvic Acid
No O2
Krebs (a.k.a. Citric Acid, TCA) cycle •  Happens in matrix in aerobic condiDons •  Pyruvic acid passes into the mitochondria •  Electrons are removed from pyruvic acid and passed on to NAD
+ and FADH •  2 ATP are produced/glucose molecule •  CO2 is produced mitochondrial-­‐disorder-­‐informaDon.com Electron Transport Chain •  Happens in the inner membrane of the mitochondria •  Enzyme called ATP synthase helps to create massive amounts of ATP •  Electron carriers from glycolysis and Kreb’s cycle aid in the process by donaDng their electrons Aerobic vs. Anaerobic Anaerobic Respira4on (glycolysis & fermenta4on) •  Energy produced quickly •  No oxygen needed •  Few ATP produced Aerobic Respira4on (glycolysis, Krebs cycle, ETC) •  Energy produced more slowly •  Oxygen needed •  More ATP are produced per molecule of glucose Blood Glucose RegulaDon •  Insulin (hormone released from pancreas) helps glucose get into cells from the bloodstream •  EaDng carbohydrates sDmulates insulin release •  Glucose is taking in by cells via facilitated diffusion •  Once inside the cell, glucose is split during glycolysis Effect of Obesity (insulin resistance) •  Insulin resistance is a condiDon where cells don’t take in glucose like they should •  This is enhanced by having too much adipose (fat) Dssue •  Can lead to type II diabetes h8p://viim.org What is Photosynthesis? The process of using sunlight to
convert CO2 and water into glucose
and oxygen
6 CO2 + 6 H2O
C6H12O6 + 6 O2
Reaction takes place in the
chloroplast
Cellular Respiration vs. Photosynthesis
CO2 (from cell respiration) O2 + carbohydrates (from photosynthesis) ConverDng Solar Energy •  Plants trap the sun’s energy using a green pigment called chlorophyll •  Chlorophyll is inside the chloroplast •  Solar energy is used to transform CO2 into sugar Factors that Affect Photosynthesis •  Water availability •  Light intensity (varies from species to species) •  Temperature (extremes slow down photosynthesis - below 0oC and above 35oC)