 Involves the release of energy and gas exchange  Occurs in all cells of all organisms  It is the release of energy from food (glucose) – “life runs on sugar”

 Energy is stored as ATP (a high energy compound) and is released and “re-stored” in a cycle Energy in Energy out Cells use a few billion ATP molecules per minute for cell activities ADP + P ATP ATP cycle clip

Anaerobic  Absence of O 2  Used by some simple organisms (yeast and bacteria)  Occurs in the cytoplasm  Partial breakdown of glucose  Less efficient (less ATP) Aerobic  uses O 2  Used by most organisms  Occurs in the mitochondria  Complete breakdown of glucose  More efficient (more ATP per glucose)

Step 1: Glycolysis: breakdown Of glucose into pyruvic acid Glucose +2 ATP (6- carbon) 4 ATP ( net gain 2 ATP, the only ATP released) 2 Pyruvic acid (3- carbon)

Pyruvic acid (from previous slide) (3- carbon) 2 Lactic Acid (no CO 2 ) 2 ethyl alcohol + 2CO 2 - In bacteria, used to make - cheese, yogurt - In humans leads to muscle fatigue when O 2 is low TOTAL ATP= 2 -in yeast, bacteria: used to make beer, wine and bread Step 2: Fermentation- pyruvic acid converted to another end product. No more ATP released. Glycolysis clip

Glucose (6- carbon +2 ATP 4 ATP ( net gain 2 ATP, the only ATP released) 2 Pyruvic acid (3- carbon) 2 Lactic Acid (no CO 2 )2 ethyl alcohol + 2CO 2 - In bacteria, used to make - cheese, yogurt - In humans leads to muscle fatigue when O 2 is low TOTAL ATP= 2 -in yeast, bacteria and used to make beer, wine and bread Glycolysis song click glucose, glucose

 Cristae in mitochondria provide a large surface area for the series of reactions that occur during aerobic respiration  Step 1: “Anaerobic Phase”- glycolysis occurs in the cytoplasm  Step 2: “Aerobic Phase”- occurs in the mitochondria  End Products: 6 CO H 2 O + 36 ATP Looks like this:

Glucose + 2ATP (6 Carbon) 4 ATP (net 2 ATP) 2 Pyruvic Acid (3 carbon) * O 2 * 2 acetyl CoA (a 2 carbon compound combined w a co-enzyme) + 2CO 2 (exhaled ) High energy 4 CO2 + 2ATP (net 2ATP) 32 ATP (net of 32 ATP) [ e- gives up energy] Krebs cycle H H O2O2 6 H 2 O (vapor) Electron Transport Chain low energy Oxidation/ Reduction final H acceptor

end products: 6 CO H 2 O + 36 ATP

Each turn of the Krebs cycle produces: 1. CO 2 2. ATP 3. Hydrogen- high energy hydrogen atoms are picked up by coenzymes NAD + FAD and carried to the electron transport chain During the e- transport chain (ETC) Oxidation occurs when some atoms lose e- ( via a gain of H) Reduction occurs when some atoms gain e- (via a loss of H) Collectively this is called oxidation- reduction Low energy H’s combine with free oxygen (the final H acceptor) to form H 2 O (vapor)

C 6 H 12 O 6 pyruvic acid + O 2 CO 2 +H 2 O + 36 ATP (aerobic) C 6 H 12 O 6 pyruvic acid lactic acid + 2ATP (anaerobic } humans and bacteria) C 6 H 12 O 6 pyruvic acid ethyl alcohol + CO ATP (anaerobic } bacteria and yeast) like our balloon demo “Cowboy respiration’ clipCowboy respiration’ clip

 The exchange of O 2 and CO 2 between an organism and the environment  the gas exchange surface must be: › Thin › Moist › In contact with O 2 › Near a transport system Adaptations for Gas Exchange 1.Monera, Protist, and Fungi- diffusion occurs across thin, moist cell membrane

2. Plants- respire 24 hours a day  gas exchange occurs in: leaves(stomates and the spongy layer  Stems (lenticles)  roots (root hairs) 3. Land Animals- the trick is to keep the respiratory surfaces moist! (see awesome adaptation sheet)

a)Cellular Aerobic : O 2 +C 6 H 12 O 6 CO 2 + H 2 O + 36 ATP Anaerobic: (when O 2 is not in high supply) C 6 H 12 O 6 lactic acid + 2ATP b) Gas exchange: occurs between the external environment through our respiratory system.

1. Nasal cavity  warms  filters (ciliated mucous membranes)  moistens air 2. Pharynx- “throat”  area where oral and nasal cavities meet 3. Larynx- “voice box”  beginning of the trachea,  mostly cartilage,  has two pairs of membranes vocal cords

4. Epiglottis  flap of cartilage that covers the larynx when you swallow  prevents choking 5. Trachea- “windpipe”  lined with ciliated mucous membranes  has cartilage rings to prevent collapse 6. Bronchi- 2 branches of the trachea  Each branch leads to a lung  Contain cartilage and ciliated mucous membranes

7. Bronchioles- smaller branches of bronchi in each lung (AKA bronchial tubes)  no cartilage  contains mucous membranes  each ends in an alveolus(plural- alveoli) 8. Alveoli- “air sacs”  Microscopic, 1 cell thick  Functional unit of resp. system where gas exchange occurs ( O 2 CO 2 )  surrounded by capillaries

9. Lung-  elastic 10. Pleura- 11. Diaphragm-  Helps to control breathing each bronchus with bronchioles and alveoli is a lung membrane surrounding the lung muscle under the lungs

Breathing - the movement of air in and out of the body a) inhalation- the diaphragm contracts and moves down  Chest cavity expands  Pressure in the cavity decreases  Air rushes into the lungs b) exhalation- diaphragm relaxes and moves up

(exhalation cont. )  Chest cavity gets smaller  Pressure in cavity increases  Air is pushed out of lungs The rate at which you breathe: - Mostly involuntary - At breaths per minute - Regulated by CO 2 concentration in blood - Chemo receptors in vessels send message to medulla in brain - High [CO 2 ]-faster rate of breathing - Low [CO 2 ]- slower - Medulla affects rate of diaphragm

Gas Exchange Capillaries surround alveoli O 2 goes into the blood Carried as oxyhemoglobin (HbO 2 ) O 2 diffuses into cells Used for aerobic respiration Products of cellular respiration (CO 2 + H 2 O) diffuse into blood * CO 2 carried in plasma once in lungs, CO 2 + H 2 O are released during exhalation

 70% as a bicarbonate ion in your plasma CO 2 + H 2 O carbonic acid bicarbonate H ion (H 2 CO 3 )(HCO 3 ) The bicarbonate ions reduce the pH in your blood and this is detected by the medulla.  20 % as carboxyhemoglobin (HbCO 2 ) on RBCs  10 % floats in your plasma as CO 2 carbonic anhydrase

Initially to compensate- hyperventilate and an increase in RBC (blood like motor oil) 25% of climbers experience: AMS- Acute Mountain Sickness brain swelling, headaches, nausea, weakness and shortness of breath  3660 meters: Some people experience HACE- High Altitude Cerebral Edema - brain swells severely - trouble walking; using hands - may hallucinate

HAPE- High Altitude Pulmonary Edema - lungs fill with fluid Mt. Everest Climbers (Summit 8848 m) - climb slowly - Use bottled O 2 - Be experienced (10-15 years)