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• What is the formula for photosynthesis?

  CO2 + H2O + Sunlight --> C6H12O6 + O2
• What is photosynthesis?


  The biochemical process by which a cell converts light energy into chemical energy, stored in glucose or other organic molecules.

  
• Why is photosynthesis important?

  - provides the primary source of oxygen in the atmosphere

  - serves as foundation of food chain

  -autotrophs require this process to make energy

  
• What are the processes in photosynthesis?

  Light-dependent and Light-independent

  
• Where do the light-dependent reactions take place?

  within the thylakoid membranes

  
• What is the function of chlorophyll?


  absorbs light energy used to produce ATP

  
• How much energy is made during the light-dependent process?

  18ATP

  
• What are the reactants of photosynthesis?

  carbon dioxide, water, and sunlight
• What are the products of photosynthesis?

  glucose and oxygen
• Explain the light-dependent reactions.

  1. Light energy is absorbed by chlorophyll

  2. The energy excited electrons in chlorophyll-a molecules

  3. The energy is used to create 18 ATP

  2. The energy is then used to split water to produce oxygen 3. The energy is used to form the energy-carrying molecules ATP and NADPH from ADP, inorganic phosphate and NADP+

  3. The electrons, having released their energy, return to the chlorophyll molecule

  
• Explain light-independent reactions.


  1. Products of light-dependent reactions (NADPH and ATP are released into the stroma of the chloroplast

  2. The hydrogen released in the light-dependent reactions combines with CO2, using all the energy formed in the light reactions, and extra ATP found in the cell, which is all used to produce glucose

  (AKA Calvin cycle)

  
• What are the factors that impact photosynthesis?

  Light intensity - increase rate until saturation point is reached

  CO2 concentration - higher concentrations increase photosynthesis rate

  Temperature - higher temps increase rate but can be detrimental at extremes

  Water availably - essential for photolysis and maintaining turgor pressure; water stress inhibits photosynthesis

  Chlorophyll concentration - higher concentrations enhance light absorption and photosynthesis activity

  Nutrient availability - deficiencies can limit photosynthesis

  Leafe surface area - larger - more area for light absorption

  Environmental factors - air pollution, altitude, humidity

  
• Compare the light-dependent reaction and the light-independent reaction.


  Light-dependent:

  Occurs in granum (thylakoid membranes)

  Not dependent on temperature

  Decomposes H2O molecules

  Makes ATP (18)

  Uses light and water (and NADP+)

  Photosystems 1&2

  Requires light

  
  

  Light-independent:

  Occurs in the stroma

  Dependent on temperature (enzymes)

  Uses those products to make glucose

  Uses ATP, CO2, and NADPH

  Calvin cycle

  Does not require light

  
• What is the formula for cellular respiration?

  C6H12O6 + 6O2 --> 6CO2 + 6H2O + ATP
• What is cellular respiration?

  The process by which cells break down glucose and other organic molecules in order to produce ATP (primary energy).

  Energy is released by cellular respiration.

  
• Why is cellular respiration important?

  All cells must perform cellular respiration to provide energy for processes such as growth, repair and maintenance.

  
• What processes occur in cellular respiration?

  Aerobic and Anaerobic

  
• What are the conditions for aerobic respiration to occur?

  Presence of oxygen

  
• How much ATP does aerobic respiration generate?

  36-38ATP

  
• What are the reactants of aerobic respiration?

  glucose and oxygen
• What are the products of aerobic respiration?

  carbon dioxide and water
• Where does aerobic respiration occur?

  cytosol and mitochondria

  
• What are the three stages of aerobic respiration?

  1. Glycolysis

  Occurs in the cytoplasm, doesn't need oxygen

  1 glucose -> pyruvic acid + 2ATP

  2. Krebs Cycle

  Occurs in the mitochondria (matrix)

  Requires O2 and co-enzyme NAD+

  Produces 2 ATP + CO2 as a by-product

  3. Electron Transport Chain

  Produces majority of ATO (32-34 molecules)

  Occurs in mitochondria

  
• What are the conditions for anaerobic respiration to occur?

  no oxygen

  
• How much ATP does anaerobic respiration generate?

  2 ATP
• What are the reactants of anaerobic respiration?

  glucose
• What are the products of anaerobic respiration?

  lactic acid (in animals)

  ethanol and carbon dioxide (plants/fungi)
• Where does anaerobic respiration occur?


  cytosol

  
• What are the stages of anaerobic respiration?

  1. Glycolysis

  2. Fermentation

  
• Homeostasis


  The relative physiological constancy of the body, maintaining conditions within small tolerance limits despite external fluctuations.
• Stimulus-response model


  Shows how an organism maintains internal balance in response to changes in its external or internal environment through receptors, processing center, and effectors.
• Receptor


  A specialized cell or group of cells that detects environmental changes (stimuli) and converts them into electrical signals sent to the processing center.
• Effector


  A part of the body that responds to signals from the processing center by carrying out actions to restore balance or produce a desired effect.
• Processing Centre (Control Centre)


  A part of the brain or gland that receives signals from receptors, interprets information, determines responses, and sends signals to effectors.
• Negative Feedback


  Stabilizes systems by reversing changes, e.g., temperature regulation.
• Positive Feedback


  Amplifies changes, moving the system further from the norm until a specific outcome is achieved, e.g., childbirth.
• Central nervous system


  Comprises the brain and spinal cord.
• Peripheral nervous system


  Consists of nerves that relay information to and from the central nervous system.
• Efferent (motor) neurons


  Transmit information from the CNS to tissues and organs (effector cells).
• Afferent (sensory) neurons


  Communicate information from tissues and organs to the CNS.