ppt kuliah respirasi
DESCRIPTION
PPT KULIAH biologi farmasi respirasi by Bu NaniTRANSCRIPT
BOTANIBOTANI FARMASIFARMASI
RESPIRASI PADA TUMBUHAN
RESPIRASI RESPIRASI PROSES PEMBENTUKAN DAN PROSES PEMBENTUKAN DAN PELEPASAN ENERGI YANG SIAP DIGUNAKAN UNTUK PELEPASAN ENERGI YANG SIAP DIGUNAKAN UNTUK PROSE PERTUMBUHAN DAN HIDUP TUMBUHAN.PROSE PERTUMBUHAN DAN HIDUP TUMBUHAN.
RESPIRASIRESPIRASITERJADI DENGAN CARA OKSIDASI PADA TEMPERATUR RENDAH DARI
KARBOHIDRAT DENGAN BANTUAN ENZIM DAN SISTEM KEHIDUPAN PADA TUMBUHAN.
MERUPAKAN REAKSI KEBALIKAN DARI FOTOSINTESIS :1. TERJADI SECARA SPESIFIK DENGAN HASIL YANG BERBEDA.
2. TERJADI PADA ORGANELA YANG BERBEDA.
RESPIRASIRESPIRASI
REAKSI KIMIA YANG TERJADI SELAMA RESPIRASI
C6H12O6 + 6O2 + 40 ADP + 40 Phosphates → 6 CO2 + 6 H2O + 40 ATP
RESPIRASI
PROSES DIMANA TERJADI PENGUBAHAN KARBOHIDRAT MENJADI ENERGI YANG SIAP DIGUNAKAN (ATP) PADA TUMBUHAN HIDUP DAN HEWAN.
1. TERJADI BERSAMAAN DENGAN FOTOSINTESIS
2. TERJADI PADA MALAM HARI3. PADA BUAH YANG TUMBUH DAN MATANG4. PADA BIJI YANG SUDAH TUA (DORMANT
SEEDS)
KAPAN RESPIRASI TERJADI ???
DIMANAKAH RESPIRASI TERJADI?DIMANAKAH RESPIRASI TERJADI?RESPIRASI TERJADI DI MITOKONDRIAMITOKONDRIA MERUPAKAN ORGANELLA YANG DITUTUP OLEH MEMBRAN YANG TERDISTRIBUSI PADA SITOSOL PADA ORGANISME EUKARIOT.FUNGSI UTAMA DARI MITOKONDRIA ADALAH UNTUK MENGUBAH MAKANAN MENJADI ENRGI YANG POTENSIAL (ATP)
KOMPENSASI CAHAYA PADA RESPIRASIKOMPENSASI CAHAYA PADA RESPIRASITINGKAT INTENSITAS CAHAYA MENENTUKAN KECEPATAN RESPIRASI
(PEMBENTUKAN CO2) DIMANA AKAN SEBANDING DENGAN KECEPATAN FOTOSINTESIS (PENGGUNAAN CO2).
TERJADI PADA TUMBUHAN YANG HIDUP DI LUAR RUNGAN.
RESPIRASI AEROB (AEROB RESPIRATION)RESPIRASI AEROB (AEROB RESPIRATION)
3 TAHAP RESPIRASI3 TAHAP RESPIRASI1. GLIKOLISIS (TERJADI DI SITOSOL)
TAHAP – TAHAP PADA LIGHT REACTIONTAHAP – TAHAP PADA LIGHT REACTION4. REDUKSI NADP MENJADI NADPH2
SIKLUS KREBS (TCA CYCLE)/SIKLUS ASAM SIKLUS KREBS (TCA CYCLE)/SIKLUS ASAM SITRATSITRAT1.TERJADI DI MATRIX MITOKONDRIA
2. SERANGKAIAN SIKLUS YANG MEMECAH PYRUVAT MENJADI C02 DAN KERANGKA KARBON YANG LAIN.
3. KERANGKA KARBON TERSEBUT DIPAKAI SEBAGAI PEMBENTUKAN PROTEIN, LEMAK, DINDING SEL, HORMON, PIGMEN,DAN MATRIX BIOLOGIS LAINNYA.
3. DIHASILKAN CO2 DAN DIHASILKAN 10 NADH
TRANSPOR ELEKTRONTRANSPOR ELEKTRON◦ ‘Oxidative Phosphorylation’◦ Series of Proteins in the Mitochondria Helps
Transfer Electrons (e-) from NADH to Oxygen Releases a Lot of Energy
◦ Occurs on Mitochondrial Inner Membrane (Proteins Bound to Membrane)
Respiration StepsRespiration Steps◦ Released Energy
Is Used to Drive the Reaction ADP + P → ATP Many ATP Are
Made◦ Oxygen Is
Required for this Step
◦ Water Is Produced
http://www.uccs.edu/~rmelamed/MicroFall2002/Chapter%205/ch05.htm
Anaerobic RespirationAnaerobic RespirationOnly 2 ATP Are Formed instead of 40
from Aerobic Respiration◦Plant Soon Runs out of Energy◦Can Begin to Suffer from Toxic Levels of
Ethanol and Related CompoundsExtended Periods of Anaerobic
Respiration will Seriously Reduced Plant Growth and Yields
Anaerobic:C6H12O6 + O2 → 2 CH2O5 + 2 H2O + 2 ATPAerobic:C6H12O6 + 6O2 + 40 ADP + 40 Phosphates → 6 CO2 + 6 H2O + 40 ATP
PhotorespirationPhotorespiration In the "normal" reaction, CO2 is
joined with RUBP to form 2 molecules of 3PGA
In the process called photorespiration, O2 replaces CO2 in a non-productive, wasteful reaction
It is believed that photorespiration in plants has increased over geologic time and is the result of increasing levels of O2 in the atmosphere--the byproduct of photosynthetic organisms themselves
The appearance of C4-type plants appears to be an evolutionary mechanism by which photorespiration is suppressed
It has long been the dream of biologists to increase the production of certain crop plants, such as wheat, that carry on C3 PS by genetically re-engineer them to perform C4 PS
It seems unlikely that this goal will be accomplished in the near future due to the complex anatomical and metabolic differences that exist between C3- and C4-type plants
PhotorespirationPhotorespirationRespiration Driven by Light EnergyDiscovered when Scientists Realized that
some Plants Have Faster Respiration Rate in Light than in Dark
Occurs in Chloroplasts and other Structures in a Photosynthetic Cell
Rubisco can React with Oxygen to Start a slightly Different Series of Rxs◦ Result in a Loss or no Net Gain of Dry Matter for
the Plant◦ Less ATP Is Produced from the Photorespiration
http://www.botany.hawaii.edu/faculty/webb/BOT311/BOT311-00/PSyn/Image81.gif
Factors Influencing Factors Influencing PhotorespirationPhotorespirationO2 : CO2 RatioIf Cells Have Low O2 but Higher CO2,
Normal PS Calvin Cycle DominatesC4 Plants Have Little Photorespiration
because They Carry the CO2 to the bundle Sheath Cells and can Build up High [CO2]◦Calvin Cycle Rxs always Favored over
PhotorespirationIf Cells Have Higher O2 and Lower CO2,
Photorespiration Dominateshttp://www.botany.hawaii.edu/faculty/webb/BOT311/BOT311-00/PSyn/Image81.gif
Factors Influencing Factors Influencing PhotorespirationPhotorespirationLight Intensity
◦Increasing Light Intensity will Increase Energy for the Photorespiration Process and for PS
◦C3 Plants Light-Saturate at Lower Light Intensities than C4 Plants Reach Their ‘Break-Even Point’ at much Lower
Light Levels due to Increasing Photorespiration
http://www.botany.hawaii.edu/faculty/webb/BOT311/BOT311-00/PSyn/Image81.gif
Factors Influencing Factors Influencing PhotorespirationPhotorespiration
Temperature◦Aerobic
Respiration and Photorespiration Increase with Temp
◦Plants Have Optimum, Minimum and Maximum Temp Ranges
http://www.botany.hawaii.edu/faculty/webb/BOT311/BOT311-00/PSyn/Image81.gif
Factors Influencing Factors Influencing PhotorespirationPhotorespiration
Net Photosynthesis or Net Assimilation Rate◦C4 Plants generally Have Net Assimilation
Rates about 2 to 3 Times that of C3 Plants◦C4 Plants Are often Called Efficient Plants
and C3 Plants Called Non-Efficient Plants◦A Few C3 Plants Have Low Respiration and
Similar Assimilation Rates as C4 Plants Sunflower Peanut
http://www.botany.hawaii.edu/faculty/webb/BOT311/BOT311-00/PSyn/Image81.gif
Factors Influencing Factors Influencing PhotorespirationPhotorespiration
Net Photosynthesis or Net Assimilation Rate◦Cooler Temps Are the only Time when C3
Plants Have Higher Net Assimilation Rates than C4 Plants PEP Carboxylase Needed to Incorporate CO2
into the 4-Carbon Structure no Longer Functions
C4 PS Rates Drop Dramatically or Stophttp://www.botany.hawaii.edu/faculty/webb/BOT311/BOT311-00/PSyn/Image81.gif
Factors Influencing Factors Influencing PhotorespirationPhotorespiration
Net Photosynthesis or Net Assimilation Rate◦Cooler Temps Are the only Time when C3
Plants Have Higher Net Assimilation Rates than C4 Plants PEP Carboxylase Needed to Incorporate CO2
into the 4-Carbon Structure no Longer Functions
C4 PS Rates Drop Dramatically or Stophttp://www.botany.hawaii.edu/faculty/webb/BOT311/BOT311-00/PSyn/Image81.gif
Factors Affecting Factors Affecting RespirationRespiration
Kind of Cell or Tissue◦Young and Developing Cells
(Meristematic Areas) usually Have Higher Respiration Rates
◦Developing and Ripening Fruit and Seeds, too
◦Older Cells and Structural Cells Respire at Lower Rates
Factors Affecting Factors Affecting RespirationRespiration
Temperature◦Respiration generally Has Higher
Optimum and Maximum Temps than PS Rxs
◦Can Have Net Dry Matter Loss at High Temps where Respiration Exceeds PS
◦Temp Refers to Temp Inside Plant or Animal Cell, not Air Temp Using Irrigation to Help Cool the Plant Can
Keep the Plant in Net Gain Range
Factors Affecting Factors Affecting RespirationRespiration
Oxygen◦Low O2 Can Reduce Aerobic Respiration
and Increase Anaerobic Respiration◦Low O2 Can Reduce Photorespiration
Factors Affecting Factors Affecting RespirationRespiration
Light◦Can Enhance Rate of Photorespiration◦Does not Directly Affect other Forms of
Respiration
Factors Affecting Factors Affecting RespirationRespiration
[Glucose]◦Adequate Glucose Needed to Carry out
Respiration◦Reductions can Occur
Reduced PS Reduced Flow of Carbohydrates in Plant
Insect Feeding Phloem Blockages
Factors Affecting Factors Affecting RespirationRespiration
[CO2]◦Higher CO2 Levels Reduce Rate of
Respiration Feedback Inhibition
◦Seldom Occurs except when O2 Levels Are Limited Flooded, Compacted Soils
Factors Affecting Factors Affecting RespirationRespiration
[ATP]◦Higher [ATP] Reduces Rate of Respiration
Feedback Inhibition◦Usually Occurs when other Metabolic
Processes Have Slowed or Stopped
Factors Affecting Factors Affecting RespirationRespiration
Plant Injury◦ Injury will Increase Respiration◦ Plant’s Growth Rate Increases in Attempt to
Recover Mechanical Damage Hail Mowing, Grazing, Cultivation, Wind
◦ Plant Synthesizes Compounds to Fight Pests Insect Feeding Diseases
◦ Some Herbicides Kill Plants by Disrupting or Affecting Respiration Generally an Indirect Effect Herbicide Disrupts Enzyme Activity or some other
Metabolic Process that will Affect Respiration
Plant Mitochondria and Plant Mitochondria and Chloroplasts May Have Evolved Chloroplasts May Have Evolved from Bacteriafrom Bacteria
Many of the features of the mitochondrial genetic system resemble those found in prokaryotes like bacteria. This has strengthened the theory that mitochondria are the evolutionary descendants of a prokaryote that established an endosymbiotic relationship with the ancestors of eukaryotic cells early in the history of life on earth. However, many of the genes needed for mitochondrial function have since moved to the nuclear genome.