Presentation on theme: "A unit to review 3 main processes cells undertake that deal with energy creation: Photosynthesis, Cellular Respiration, and Fermentation Cellular Processes."— Presentation transcript:
A unit to review 3 main processes cells undertake that deal with energy creation: Photosynthesis, Cellular Respiration, and Fermentation Cellular Processes
Energy 2 Energy Takes Many Forms such as light, heat, electrical, chemical, mechanical, etc. Energy can be changed from one form to another Energy can be stored in chemical bonds & then released later Candles release energy as HEAT & LIGHT
PHOTOSYNTHESIS The process of converting sunlight into FOOD that can be used by the plant cell. This process DOES NOT create energy for the plant.
It Begins with Sunlight! 4
Energy for Life on Earth 5 Sunlight is the ULTIMATE energy source for all life on Earth Plants store energy in the chemical bonds of sugars Chemical energy is released as ATP during cellular respiration
Photoautotrophs Absorb Light Energy 6
Autotrophs 7 Autotrophs include organisms that make their own food Some use the sun’s energy directly Euglena
Autotrophs 8 Plants, and some other organisms that contain chlorophyll, are able to use light energy from the sun to produce food.
Heterotrophs 9 Heterotrophs can NOT directly use the sun’s energy Heterotrophs are organisms that must consume (eat) other organisms for food
Plants 10 Autotrophs – produce their own food (glucose) Process called photosynthesis Mainly occurs in the leaves: a.stoma - pores b.mesophyll cells Stoma Mesophyll Cell Chloroplast
Stomata (stoma) 11 Pores in a plant’s cuticle through which water vapor and gases (CO 2 & O 2 ) are exchanged between the plant and the atmosphere. Guard Cell Carbon Dioxide (CO 2 ) Oxygen (O 2 )
Chlorophyll Molecules 12 Located in the thylakoid membranes Chlorophyll pigments harvest energy (photons) by absorbing certain wavelengths (blue-420 nm and red-660 nm are most important) Plants are green because the green wavelength is reflected, not absorbed.
Inside A Chloroplast 13
Absorption of Light by Chlorophyll 14 wavelength Absorption violet blue green yellow orange red Chlorophyll absorbs blue-violet & red light best
Fall Colors 15 In addition to the chlorophyll pigments, there are other pigments present During the fall, the green chlorophyll pigments are greatly reduced revealing the other pigments Carotenoids are pigments that are either red, orange, or yellow
Photosynthesis 16 Anabolic (small molecules combined) Endergonic (stores energy) Carbon dioxide (CO 2 ) requiring process that uses light energy (photons) and water (H 2 O) to produce organic macromolecules (glucose). 6CO 2 + 6H 2 O C 6 H 12 O 6 + 6O 2 + ATP glucose SUN photons
The Photosynthesis Equation 17
Factors Affecting the Rate of Photosynthesis Amount of available water Temperature Amount of available light energy 18
Two Parts of Photosynthesis 19 Two reactions make up photosynthesis: Light Reaction or Light Dependent Reaction Produces energy from solar power (photons) in the form of ATP and NADPH. Calvin Cycle or Light Independent Reaction Also called Carbon Fixation or C 3 Fixation Uses energy (ATP and NADPH) from light reaction to make sugar (glucose).
Photosynthesis Overview 20
Light Dependent Reaction 21 Reactants: H 2 O Light Energy Products: ATP NADPH
The Calvin Cycle 22 Uses ATP and Uses ATP and NADPH from NADPH from light reaction light reaction as energy as energy Uses CO 2 Uses CO 2 To produce To produce glucose glucose
C 3 Plants Temperate environement 85% of all plants (evergreens, grain plants, deciduous trees) Stomates open during day and closed at night Leaves with larger air spaces 23
C 4 Plants Hot, moist environments 3% of plants (weeds [crabgrass], corn, sugarcane) Stomates open during day and closed at night Thinner leaves with less air space 24
CAM Plants 25 Hot, dry environments 8% of plants (cactus and ice plants) Stomates closed during day and open during the night Thick fleshy leaves
Structure of ATP 26 ATP stands for adenosine triphosphate Composed of a nitrogen base (adenine), the pentose (5C) sugar (ribose), and three phosphate groups. The last phosphate group is bonded with a HIGH ENERGY chemical bond This bond can be broken to release ENERGY for cells to use High Energy Phosphate Bond
Removing a Phosphate from ATP 27 Breaking the last phosphate bond from ATP will: Release ENERGY for cells to use Form ADP Produce a free phosphate group Energy
Releasing Energy From ATP 28 ATP is constantly being used and remade by cells ATP provides all of the energy for cell activities The high energy phosphate bonds can be broken to release energy The reforming the ATP molecule is called phosphorylation (joining free phosphate and ADP together)
Releasing Energy From ATP 29 Adding A Phosphate Group To ADP stores Energy in ATP Removing A Phosphate Group From ATP Releases Energy & forms ADP Lose Gain
More on ATP 30 Cells have enough ATP to last for a few seconds ATP must constantly be made ATP transfers energy very well ATP is NOT good at energy storage
Cells Using Biochemical Energy 31 Cells Use ATP For: Active transport Movement Photosynthesis Protein Synthesis Cellular respiration All other cellular reactions
Glucose 32 Glucose is a monosaccharide C 6 H 12 O 6 One molecule of glucose stores 90 times more chemical energy than one molecule of ATP
Cell Respiration The process of using glucose (sugar) and O 2 (oxygen) to create energy (ATP) for all cells.
When is ATP Made in the Body? During a process called Cellular Respiration that takes place in both plants & animals Cellular Respiration breaks down the glucose molecules to release energy. 34
Equation for Cellular Respiration 6CO 2 + 6H ATP’s C 6 H 12 O 6 + 6O 2 yields 35
Cellular Respiration Requires oxygen Metabolic Pathway that breaks down carbohydrates Breakdown of one glucose results in 36 to 38 ATP molecules Glucose is oxidized and O 2 is reduced, therefore is an oxidation-reduction reaction. Process is Exergonic as High-energy Glucose is broken into CO 2 and H 2 O Process is also Catabolic because larger Glucose breaks into smaller molecules 36
Where Does Cellular Respiration Take Place? It actually takes place in two parts of the cell: Glycolysis occurs in the cytoplasm Krebs Cycle & ETC take place in the mitochondria 37
Stages of Cellular Respiration 1. Glycolysis Occurs in cytoplasm, anaerobic and aerobic, uses two ATP and produces 4, splits glucose into two pyruvate molecules 2. The Krebs Cycle Occurs in matrix (mitochondria), aerobic, occurs twice (creates 1 ATP each cycle), releases CO 2 and two ATP molecules 38
Stages of Cellular Respiration Electron Transport Chain Occurs in the inner membrane (mitochondria), aerobic, creates 34 ATP molecules and releases H2O The end result of Cellular Respiration is 38 ATP molecules.
Fermentation The process of creating energy in the absence of O 2.
Fermentation Occurs when O 2 NOT present (anaerobic) Called Lactic Acid fermentation in muscle cells (makes muscles tired) Called Alcoholic fermentation in yeast (produces ethanol) Nets only 2 ATP 41