How Is a Marathoner Different from a Sprinter? Muscles in human legs contain two different types of muscle fibers Marathoners have more slow-twitch fibers, which perform better in endurance exercises Sprinters have more fast-twitch fibers, which perform best in short bursts of intense activity
The different types of muscle fibers use different processes for making ATP Slow-twitch fibers undergo aerobic (in the presence of O2) respiration Fast-twitch fibers undergo anaerobic (in the absence of O2) respiration Cellular respiration is the process by which cells produce energy aerobically
Animal Plant Food serves as a source of raw materials for the cells in the body and as a source of energy. Food serves as a source of raw materials for Animal the cells Cells in the body and as a source of energy. Mitochondrion Plant Cells
Both plant and animal cells carry out the final stages of cellular respiration in the mitochondria. Animal Cells Outer membrane Intermembrane space Mitochondrion Inner membrane Matrix Plant Cells
Photosynthesis and cellular respiration provide energy for life All living organisms require energy to maintain homeostasis, to move, and to reproduce Photosynthesis converts energy from the sun to glucose and O2 Cellular respiration breaks down glucose and releases energy in ATP Energy flows through an ecosystem; chemicals are recycled
Breathing supplies oxygen to our cells and removes carbon dioxide Breathing and cellular respiration are closely related Breathing brings O 2 into the body from the environment O 2 is distributed to cells in the bloodstream In cellular respiration, mitochondria use O 2 to harvest energy and generate ATP Breathing disposes of the CO 2 produced as a waste product of cellular respiration
O 2 CO 2 Breathing Lungs CO 2 Bloodstream O 2 Muscle cells carrying out Cellular Respiration Glucose O 2 CO 2 H 2 O ATP
Cellular respiration banks energy in ATP molecules The reactants O 2 and glucose regroup to form the products CO 2 and H 2 O Energy from glucose is released and stored in ATP
Glucose Oxygen gas Carbon dioxide Water As a result of respiration, energy is released from the chemical bonds and used for the production of ATP. Energy The respiration reactions are controlled by ENZYMES
CONNECTION The human body uses energy from ATP for all its activities The body needs a continual supply of energy to maintain basic functioning In addition, ATP supplies energy (kilocalories) for voluntary activities An average adult human needs about 2,200 kcal of energy each day
Cellular Respiration There are two types of Respiration: Anaerobic Respiration Aerobic Respiration
Aerobes Aerobes are organisms that use the Aerobic Respiration pathway. Aerobes require oxygen.
Anaerobes Anaerobes are organisms that use the Anaerobic Respiration pathway Most anaerobes are bacteria (not all). Anaerobes do NOT require oxygen.
Aerobic Respiration The Advantages Aerobic respiration is so fast that cells can produce thousands of ATP molecules in a few milliseconds.
ATP Sum Max = 38 ATPs per glucose
However... Some energy (2 ATP s) is used to shuttle compounds into the mitochondria..so, some biologists teach there is an actual ATP yield of 36 ATP s per glucose.
Name each of these cells, describe their relative numbers of mitochondria and explain why they have that number.
Anaerobic Respiration Anaerobic Respiration does NOT require oxygen! The 2 most common forms of Anaerobic Respiration are: 1. Alcoholic Fermentation, and 2. Lactic Acid Fermentation
Alcoholic Fermentation is carried out by yeast, a kind of fungus.
Alcoholic Fermentation Does NOT require O2 Produces CO 2 and ethanol Produces 2 ATPs.
Fermentation Alcoholic Fermentation Yeasts and a few other microorganisms use alcoholic fermentation, forming ethyl alcohol and carbon dioxide as wastes. The equation for alcoholic fermentation: glucose ethanol + CO2 + some energy C 6 H 12 O 6 2CH 3 CH 2 O + 2CO 2
Question Why is the alcohol content of wine always around 12-14%? Because Alcohol is toxic and kills the yeast at high concentrations. Oh Yeah..The Holes in Swiss Cheese are bubbles of CO2 from fermentation.
Importance of Fermentation Alcohol Industry - almost every society has a fermented beverage. Baking Industry - many breads use yeast to provide bubbles to raise the dough.
Fermentation Lactic Acid Fermentation In many cells, glucose can be converted to lactic acid. This type of fermentation is called lactic acid fermentation. It generates 2 ATPs. The equation for lactic acid fermentation: glucose lactic acid + some energy
Lactic Acid Fermentation Carried out by human muscle cells under oxygen debt. Lactic Acid is a toxin and causes fatigue, soreness and stiffness in muscles.
Comparing Aerobic and Anaerobic Respiration Aerobic Respiration- requires a mitochondrion and oxygen is a three phase process Produces 38 ATPs Anaerobic does not require oxygen consists of one phase only Produces 2 ATPs