Cellular Respiration and Photosynthesis

The yeast lab Are yeast an animal or a plant? Technically neither. They’re a fungus. So What does that mean? Domain Kingdom Phylum (Division used in Plants) Class Order Family Genus Species Remembering the order: Did King Philip Come Over For Great Soup?

Kingdoms of organisms Cell Structure  Prokaryotes – have a lack of membrane bound structures, rigid, form protein like chains, single strand of DNA, plasmids  Eukaryotes – larger, have membrane bond structures, DNA is organized in nucleus, do not have plasmids

Kingdom of organisms 1. Archaebacteria (ancient bacteria) = can live in extreme conditions 2. Eubacteria (true bacteria) = most use oxygen 3. Protista  All eukaryotic.  Single celled organisms  Ex: Euglena and Paramecium 4. Plantae  Multicellular eukaryotes that photosynthesis to produce food. (autotrophy) 5. Animalia  Multicellular eukaryotes, Heterotrophs that range in size

Kingdoms of organisms 6. Fungi  Heterotrophy (must consume food)  Eukaryotes  Unicellular and multicellular  Absorb small molecules from surroundings (food) generally are decomposers  Example: molds, yeasts and fungi

So what did the yeast do? Fermentation  No oxygen present-Anaerobic pathway  Pyruvic acid converted into  Lactic acid or ethyl alcohol  No ATP created  Regenerates an electron carrier molecule that keeps glycolysis going = keeps ATP in production

Important in manufacturing yogurt and cheese Occurs in your muscle cells during strenuous exercise.  When oxygen is depleted at faster rate than can be supplied to cells, cells switch from aerobic to anaerobic respiration  Lactic acid accumulates in muscle cells (in cytosol)  Increased acidity in cytosol reduces cells capacity to contract = fatigue, pains, muscle cramps Lactic Acid Fermentation

Alcoholic Fermentation Example - Yeast Converts pyruvic acid into ethyl alcohol Important to wine and beer industry Yeast added to fermentation mixture  Ethyl alcohol accumulates until it reaches a concentration that inhibits fermentation

So the yeast performed cellular respiration Conditions for Cellular Respiration  Oxygen present – Aerobic respiration  Majority of ATP occurs in this process (makes 36 ATP molecules)  Oxygen absent – Anaerobic respiration  No ATP created

Equation for Cellular Respiration C 6 H 12 O 6 + 6O 2  6CO 2 + 6H 2 O + energy Reactants = Glucose (sugar), Oxygen Products = Carbon dioxide, Water, ATP

What is ATP? ATP – Adenosine Triphosphate are the energy- storing molecule. Without ATP supplying the cell with an abundant supply of energy the cell would die.

Where does cellular respiration occur? In the Mitochondria!!!!

Do plants undergo cellular respiration? YES!!!!! Cellular respiration does not mean breathing – it is breaking down organic compounds to release stored energy.

Plants also undergo photosynthesis Where photosynthesis occurs: chloroplast Outer membrane Thylakoid Stroma Granum

Chloroplasts contain chlorophyll  Chlorophyll a  Only chlorophyll a is directly involved in light reaction of photosynthesis  Chlorophyll b helps to capture light energy = accessory pigment

Equation for Photosynthesis 6CO 2 + 6H light energy  C 6 H 12 O 6 + 6O 2 Reactants – Carbon dioxide, water, and light Products – Glucose and Oxygen

How does the water and CO2 get into the plant? Xylem  A structure in the stem of a plant that moves water from the roots to the leaves. Stomata  Openings on the leaf that allow gases to move in and out.  Surrounded by guard cells that can open and close as necessary.

What factors affect the rate of photosynthesis? Affected by plant’s environment  Light intensity-  as light , photosynthesis  until light saturation point.  Carbon Dioxide CO 2 , photosynthesis   Temperature  Chemical reactions general  with temperature  If it gets to hot the enzymes can denature and the reaction 