Photosynthesis & Respiration Cellular Energy Photosynthesis & Respiration

Energy Flow Sun  Glucose (photosynthesis)  ATP (Respiration)

Cell Energy Energy ~ The ability to do work. Main source of energy in living things: Glucose! C6H12O6 Glucose is a monosaccharide. Glucose is made by photosynthesis for autotrophs. Glucose is part of food eaten by heterotrophs. Glucose is powerful – it must be turned into a gentler form of energy called ATP to be used by a cell.

Glucose C6H12O6

How do you get glucose? Autotroph ~ Organism that makes its own food (glucose) by photosynthesis. Ex: plant Heterotroph ~ Organism that must eat food (glucose) from an outside source. Ex: human

Energy Storing Compounds NADPH ATP

ATP Adenosine Triphosphate ATP is an energy storing compound made in the mitochondria. It is made when glucose is broken down. ADENOSINE PO4 PO4 PO4

ATP http://www.biologyinmotion.com/atp/index.html Be sure to watch!

Cellular Organelles Chloroplasts: plant cells; energy from the sun is converted into glucose Mitochondria: glucose is converted into ATP

Chloroplast Structure Outer and Inner membranes contain and protect the inner parts Stroma: area where reactions occur and sugars are created Thylakoids: have chlorophyll molecules on their surface Chlorophyll – pigment that uses sun’s energy to create glucose Stroma lamella: act like the skeleton of the chloroplast, keeping all of the sacs a safe distance from each other and maximizing the efficiency of the organelle.

Mitochondria Outer membrane Cristae: the folds Matrix: contains high number of enzymes; several steps of cellular respiration are performed here DNA Ribosomes

Photosynthesis A chemical reaction in which light energy is converted into bond energy stored in a glucose molecule.

Photosynthesis Reaction Requirements for photosynthesis: Carbon dioxide (CO2) Water (H2O) Light Chlorophyll Products of photosynthesis: Glucose (C6H12O6) Oxygen (O2)

Plant Pigments Chlorophyll - green Xanthophyll - yellow Carotene - orange Anthocyanins *Plant Pigments absorb energy and pass on to chlorophyll

Chlorophyll Chlorophyll is green in color, meaning that green light is reflected, not absorbed. Chlorophyll absorbs primarily red and blue light for photosynthesis.

What is happening? Red Light: Green Light:

Light Reactions Starting molecules: CO2, H2O Ending molecules: O2, NADPH, ATP e-

Dark Reactions (Calvin Cycle) Starting molecules: Ending molecules: CO2 C6H12O6 C5

Cellular Respiration Chemical reactions that convert glucose into ATP. May or may not use oxygen. Occurs in mitochondria.

Aerobic Respiration Oxygen Glucose 36 ATP Water Carbon dioxide Materials Needed: Materials Made: Oxygen Glucose 36 ATP Water Carbon dioxide

Anaerobic Respiration Breaks down glucose without using oxygen. Produces a poisonous waste product. Only produces 2 ATP molecules from one glucose molecule. Two types of anaerobic respiration: Alcoholic fermentation Lactic acid fermentation

Lactic Acid Fermentation C6H12O6 CO2 + lactic acid + 2ATP Produces lactic acid as a waste product. Carried out by bacteria. Causes milk to go sour. Carried out by human muscle cells (reason you are sore after a workout) Used in industry to make cheese and yogurt.

Alcoholic Fermentation C6H12O6 CO2 + alcohol + 2ATP Yeasts and other microorganisms carry out alcoholic fermentation Formation of ethyl alcohol and carbon dioxide as wastes Causes bread dough to rise

Aerobic vs. Anaerobic Respiration Uses O2. Breaks down glucose. Produces 36 ATP. Carried out by plants and animals. Does not use O2. Breaks down glucose. Produces 2 ATP. Alcoholic fermentation is carried out by yeast. Lactic acid fermentation is carried out by bacteria.

Aerobic organisms An organism that requires oxygen

Anaerobic organisms An organism that does not require oxygen

Photosynthesis vs. Respiration Produces C6H12O6 (glucose). Occurs in the chloroplasts. Produces O2 (oxygen gas). Carried out by autotrophs. Produces ATP. Occurs in the mitochondria. Produces CO2 (carbon dioxide). Carried out by heterotrophs and autotrophs. Aerobic respiration produces 36 ATP, anaerobic 2 ATP.