Cellular Respiration

Both plant and animal cells carry out the final stages of cellular respiration in the mitochondria. Outer membrane Intermembrane space Mitochondrion Inner membrane Photo Credits: left: ©Bob Gurr/DRK Photo; middle bottom: ©John Durham/Science Photo Library/Photo Researchers, Inc. ; middle top: ©Ron Boardman/Stone; right: ©Keith Porter/Photo Researchers, Inc. Matrix Plant Cells 2

But first: Cellular Energy. Chemical reactions in cells require energy to get started = activation energy. Can be endergonic= use (store) energy or exergonic= release energy www.southtexascollege.edu/modeh/1408webpage_files/CH6_files/image003.jpg&imgrefurl=http://www.southtexascollege.edu/modeh/1408webpage_files/CH6.htm&usg=__P6-_4tWlMbpjq5LuN1BcEquw9h4=&h=250&w=469&sz=21&hl=en&start=0&zoom=1&tbnid=45Ll12d7qvXKyM:&tbnh=89&tbnw=167&prev=/images%3Fq%3Dexergonic%2Breaction%26um%3D1%26hl%3Den%26sa%3DN%26biw%3D1366%26bih%3D575%26tbs%3Disch:1&um=1&itbs=1&iact=hc&vpx=98&vpy=296&dur=3458&hovh=164&hovw=308&tx=89&ty=187&ei=kzsfTcehM8GqlAewnaDaCw&oei=kzsfTcehM8GqlAewnaDaCw&esq=1&page=1&ndsp=21&ved=1t:429,r:14,s:0

But first we need to lower the energy. How can the cell do this? http://littlezhelovesmarshmallows.blogspot.com/2008_09_01_archive.html

A catalyst or enzyme can lower this for the cell! Enzymes performance can be affected by Heat, pH, and concentration of the substrate (molecules enzymes act on).

Cellular Respiration C6H12O6 + 6O2 6CO2 + 6H2O + ATP How energy (ATP) and water are created using glucose and oxygen (An exergonic reaction) C6H12O6 + 6O2 6CO2 + 6H2O + ATP Does this Equation look familiar?? 6

What is created?? 38 ATP!!!!! A compound Used To Store Energy In Living Organisms 7

So how do we get the ATP???

What do cells use ATP For: Active transport Movement Photosynthesis Protein Synthesis Cellular respiration All other cellular reactions Amoeba 9

More on ATP Cells Have Enough ATP To Last For A Few Seconds ATP must constantly be made ATP Transfers Energy Very Well ATP Is NOT Good At Energy Storage 10 10

So what happens when Oxygen is not present? anaerobic respiration (Fermentation) Called Lactic Acid in muscle cells! Called Alcoholic fermentation in yeast (produces ethanol) Nets only 2 ATP (from glycolysis) How does that compare to aerobic respiration? 11

Electron transport chain Process Products Glucose Anaerobic without oxygen Aerobic with oxygen Glycolysis Pyruvic acid +2 ATP Fermentation Kreb’s cycle Ethyl alcohol (0 ATP) Electron transport chain Or Lactic acid (0 ATP) 36 ATP Carbon dioxide

Types of organisms Obligate aerobes: Must have oxygen to survive What type of cellular respiration will these organisms use? Obligate anaerobes: cannot survive if oxygen is present Peptostreptococcus can cause brain, liver, breast, and lung abscesses, as well as generalized necrotizing soft tissue infections. Commensal organisms in humans, living predominantly in the mouth, skin, gastrointestinal, and urinary tracts, and compose a portion of the bacterial gut flora. Under immunosuppressed or traumatic conditions these organisms can become pathogenic, as well as septicemic, harming their host. Salmonella: They cause illnesses like typhoid fever, paratyphoid fever, and the foodborne illness. Found worldwide in cold- and warm-blooded animals (including humans), and in the environment. Facultative anaerobes: prefer to use oxygen but can survive without it if needed

How are Photsynthesis and Cellular Respiration related?