2.35: Know that ATP Provides Energy for Cells

ATP (ADENOSINE TRIPHOSPHATE): High energy molecule that functions as an immediate source fo power for cell processes

ATP PRODUCTION BY RESPIRATION

Diagram showing the Production of ATP from Respiration

EQUATION:

EXPLANATION: ATP (Adenosine Triphosphate) contains three covalently bonded Phosphate groups that store potential energy between their bonds This potential energy is released and used by the cell when the end Phosphate is removed from ATP, forming Adenosine Triphosphate (ADP) and Phosphate (Pi) Cell respiration can regenerate ATP from the resulting ADP + Pi by using energy in organic compounds (involves oxidation) This is a continuous cycle, allowing molecules to be recycled to provide a constant source of immediate energy in the cell to facilitate metabolic pathway

2.34: Understand How the Process of Respiration Produces ATP in Living Organisms

ATP (ADENOSINE TRIPHOSPHATE): High energy molecule that functions as an immediate source fo power for cell processes

ATP PRODUCTION BY RESPIRATION

Diagram showing the Production of ATP from Respiration

EQUATION:

EXPLANATION: ATP (Adenosine Triphosphate) contains three covalently bonded Phosphate groups that store potential energy between their bonds This potential energy is released and used by the cell when the end Phosphate is removed from ATP, forming Adenosine Diphosphate (ADP) and Phosphate (Pi) Cell respiration can regenerate ATP from the resulting ADP + Pi by using energy in organic compounds (involves oxidation) This is a continuous cycle, allowing molecules to be recycled to provide a constant source of immediate energy in the cell to facilitate metabolic pathway

2.36: Describe the Differences between Aerobic and Anaerobic Respiration

*AEROBIC RESPIRATION: Breakdown of Glucose in the presence of Oxygen to produce Carbon Dioxide and Water to release energy; occurs in the Mitochondria of the cell

EQUATION:

s

Glucose      +      Oxygen       →       Carbon Dioxide      +      Water

s

s

*ANAEROBIC RESPIRATION: Breakdown of Glucose in the absence of Oxygen to produce Lactic acid (and small amounts of energy) in humans, and Carbon dioxide and Ethanol (and small amounts of energy) in yeast and plants; occurs during exercise and causes cramps in humans (due to build-up of Lactic acid)

EQUATION FOR ANAEROBIC RESPIRATION (HUMANS):

s

Glucose       →       Lactic Acid

s

EQUATION FOR ANAEROBIC RESPIRATION (YEAST AND PLANTS):

s

Glucose       →       Ethanol      +      Carbon Dioxide

2.38: Know the Word Equation for Anaerobic Respiration in Plants and in Animals

ANAEROBIC RESPIRATION: Breakdown of Glucose in the absence of Oxygen to produce Lactic acid (and small amounts of energy) in humans, and Carbon dioxide and Ethanol (and small amounts of energy) in yeast and plants; occurs during exercise and causes cramps in humans (due to build-up of Lactic acid)

EQUATION FOR ANAEROBIC RESPIRATION (HUMANS):

s

Glucose       →       Lactic Acid

s

EQUATION FOR ANAEROBIC RESPIRATION (YEAST AND PLANTS):

s

Glucose       →       Ethanol      +      Carbon Dioxide

2.37: Know the Word Equation and the Balanced Chemical Symbol Equation for Aerobic Respiration in Living Organisms

AEROBIC RESPIRATION: Breakdown of Glucose in the presence of Oxygen to produce Carbon Dioxide and Water to release energy; occurs in the Mitochondria of the cell

EQUATION:

2.39: Practical: Investigate the Evolution of Carbon Dioxide and Heat from Respiring Seeds or Other Suitable Organisms

INVESTIGATING EVOLUTION OF CARBON DIOXIDE

Diagram showing the use of Respiring Organisms to Investigate Carbon Dioxide Production

METHOD: One end of a capillary tube is attached to a flask of Sodium Hydroxide to allow the inflow of air (inlet pipe) This flask is connected by a capillary tube to a flask of Hydrogen Carbonate (indicator A) This flask is connected by a capillary tube to a flask of respiring organism (e.g worms) This Flask is connected by a capillary tube to a flask of Hydrogen Carbonate (indicator B) Lastly, one end of a capillary tube is attached to this flask to allow the outflow of Air (outlet pipe)

RESULT: As air enters the first capillary tube, Sodium Hydroxide will absorb and remove Carbon Dioxide, therefore causing Hydrogen Carbonate indicator to turn red (indicator A) As air (deficient of Carbon Dioxide but abundant in Oxygen) enters the flask of respiring organisms, organisms will respire aerobically to produce Carbon Dioxide as waste product, therefore causing Hydrogen Carbonate indicator to turn Yellow (indicator B) This hence shows the production of Carbon Dioxide by living organisms, showing the evolution of Carbon Dioxide

INVESTIGATING EVOLUTION OF HEAT

Diagram showing the Use of Thermo Flasks with Seeds to investigate the Evolution of Heat

METHOD: Two thermo flasks are set up - one with germinating seeds and another with boiled seeds Thermometer wrapped in cotton wool is added into each thermo flask; cotton wool prevents the loss of heat Thermometer is used to measure and record the initial temperature in both thermo flasks After a fixed number of days, thermometer is used to measure and record the final temperature in both thermo flasks

RESULT: As germinating seeds are alive, they will respire aerobically to produce energy in the form of heat, therefore causing temperature of thermo flask to increase after the fixed period of time As boiled seeds are dead, they will not respire and therefore will not produce heat energy, causing temperature of thermo flask to remain constant after the fixed period of time Hence, this shows that living organisms respire to release energy in the form heat, therefore showing the evolution of heat