Disanje - Dušan Kostic - Jasmina MiljkovićNašaŠkola.Net
Takmičenje na portalu www.nasaskola.net
"biramo najbolju lekciju"
februar 2012. godine,
Disanje,
Biologija,
Dušan Kostić, III-4,
Jasmina Miljković,
Prva niška gimnazija "Stevan Sremac"
This presentation describes in details how photosynthesis works along with its process. This presentation also shows the raw materials required for photosynthesis. It also shows the significance of photosynthesis.
Disanje - Dušan Kostic - Jasmina MiljkovićNašaŠkola.Net
Takmičenje na portalu www.nasaskola.net
"biramo najbolju lekciju"
februar 2012. godine,
Disanje,
Biologija,
Dušan Kostić, III-4,
Jasmina Miljković,
Prva niška gimnazija "Stevan Sremac"
This presentation describes in details how photosynthesis works along with its process. This presentation also shows the raw materials required for photosynthesis. It also shows the significance of photosynthesis.
Plants and algae perform photosynthesis, which converts carbon dioxide and water into glucose and oxygen using energy from sunlight. Photosynthesis occurs in chloroplasts and uses chlorophyll to absorb light, which drives the production of ATP and NADPH that fuel the Calvin cycle to produce glucose from carbon dioxide. It is an essential process that generates oxygen and forms the base of the food chain sustaining all life on Earth.
The document summarizes the organization of the mitochondrial electron transport chain. It describes the five complexes of the electron transport chain (Complexes I-V), including their components, functions, and electron transfer processes. Specifically, it details how Complexes I, III, and IV transfer electrons from donors like NADH to final acceptors like oxygen. This generates a proton gradient across the inner mitochondrial membrane, which Complex V then uses to synthesize ATP through oxidative phosphorylation.
The document summarizes key concepts about energy transformations that occur in the human body through respiration and oxidative phosphorylation. Chemical energy from nutrients is converted to ATP through substrate-level phosphorylation and oxidative phosphorylation. Oxidative phosphorylation uses the electron transport chain in the mitochondria to generate a proton gradient across the inner mitochondrial membrane, which drives ATP synthesis from ADP and inorganic phosphate.
The document summarizes two important biogeochemical cycles - the nitrogen cycle and the carbon dioxide-oxygen cycle.
The nitrogen cycle describes how nitrogen exists in different forms and moves between the atmosphere, living things, and the lithosphere through natural processes like nitrogen fixation, assimilation, decomposition, nitrification, and denitrification. Human activities like using nitrogen fertilizers and burning fossil fuels can impact the nitrogen cycle.
The carbon dioxide-oxygen cycle explains how carbon dioxide and oxygen are exchanged between living things and the atmosphere through photosynthesis, respiration, and combustion. Photosynthesis produces oxygen and food, respiration uses oxygen and food to produce energy, and combustion releases carbon dioxide through burning fuels. Human activities such as def
The document summarizes 14 famous tourist attractions in France. It describes the Eiffel Tower as a symbol of Paris and the most visited paid attraction in the world. It notes that Mont St. Michel is a small rock island known for its abbey and church in Normandy. It also mentions that the Palace of Versailles was built by Louis XIV and is famous for its luxurious furnishings and gardens.
The document discusses global religious demographics and the major world religions, including:
- Christianity has the most adherents with over 2.1 billion, followed by Islam with 1.3 billion and secularism/non-religion with 1.1 billion.
- It provides statistics on the number of adherents of several other religions like Hinduism, Chinese folk religion, Buddhism, African traditional religions, and others.
- Tables show the branches of the largest religions and their numbers of adherents, such as Catholics, Sunnis, Vaishnavites, Orthodox, etc.
- Maps and charts illustrate the geographical distribution of major religions like Christianity, Islam, Hinduism, and others around the world.
-
This document provides an overview of photosynthesis presented by a group of 6 students. It describes the key processes and phases of photosynthesis including light reaction, dark reaction, photophosphorylation, photosystems, and alternative pathways such as C4 and CAM photosynthesis. The light reaction uses energy from sunlight to split water and produce ATP and NADPH. The dark reaction then uses these products to fix carbon from carbon dioxide into sugars.
Carbon cycles between the atmosphere, organisms, oceans, and lithosphere. Plants absorb carbon dioxide from the air through photosynthesis, and animals obtain carbon by eating plants or other animals. When organisms die, decomposers release carbon back into the atmosphere or it becomes trapped underground in fossil fuels and other deposits. Human activities like burning fossil fuels have increased the amount of carbon dioxide in the atmosphere, contributing to global warming.
The document outlines the process of photosynthesis through 6 main topics: plant structure, pigments and absorbance spectrum, light-dependent reactions, Calvin cycle, and photorespiration. It discusses the key organelles and structures involved in photosynthesis in plant leaves like chloroplasts, stomata, and mesophyll tissue. It also explains the light and dark reactions of photosynthesis, including the light-dependent reaction where light energy is captured and the Calvin cycle where carbon is fixed into glucose.
Plants and algae perform photosynthesis, which converts carbon dioxide and water into glucose and oxygen using energy from sunlight. Photosynthesis occurs in chloroplasts and uses chlorophyll to absorb light, which drives the production of ATP and NADPH that fuel the Calvin cycle to produce glucose from carbon dioxide. It is an essential process that generates oxygen and forms the base of the food chain sustaining all life on Earth.
The document summarizes the organization of the mitochondrial electron transport chain. It describes the five complexes of the electron transport chain (Complexes I-V), including their components, functions, and electron transfer processes. Specifically, it details how Complexes I, III, and IV transfer electrons from donors like NADH to final acceptors like oxygen. This generates a proton gradient across the inner mitochondrial membrane, which Complex V then uses to synthesize ATP through oxidative phosphorylation.
The document summarizes key concepts about energy transformations that occur in the human body through respiration and oxidative phosphorylation. Chemical energy from nutrients is converted to ATP through substrate-level phosphorylation and oxidative phosphorylation. Oxidative phosphorylation uses the electron transport chain in the mitochondria to generate a proton gradient across the inner mitochondrial membrane, which drives ATP synthesis from ADP and inorganic phosphate.
The document summarizes two important biogeochemical cycles - the nitrogen cycle and the carbon dioxide-oxygen cycle.
The nitrogen cycle describes how nitrogen exists in different forms and moves between the atmosphere, living things, and the lithosphere through natural processes like nitrogen fixation, assimilation, decomposition, nitrification, and denitrification. Human activities like using nitrogen fertilizers and burning fossil fuels can impact the nitrogen cycle.
The carbon dioxide-oxygen cycle explains how carbon dioxide and oxygen are exchanged between living things and the atmosphere through photosynthesis, respiration, and combustion. Photosynthesis produces oxygen and food, respiration uses oxygen and food to produce energy, and combustion releases carbon dioxide through burning fuels. Human activities such as def
The document summarizes 14 famous tourist attractions in France. It describes the Eiffel Tower as a symbol of Paris and the most visited paid attraction in the world. It notes that Mont St. Michel is a small rock island known for its abbey and church in Normandy. It also mentions that the Palace of Versailles was built by Louis XIV and is famous for its luxurious furnishings and gardens.
The document discusses global religious demographics and the major world religions, including:
- Christianity has the most adherents with over 2.1 billion, followed by Islam with 1.3 billion and secularism/non-religion with 1.1 billion.
- It provides statistics on the number of adherents of several other religions like Hinduism, Chinese folk religion, Buddhism, African traditional religions, and others.
- Tables show the branches of the largest religions and their numbers of adherents, such as Catholics, Sunnis, Vaishnavites, Orthodox, etc.
- Maps and charts illustrate the geographical distribution of major religions like Christianity, Islam, Hinduism, and others around the world.
-
This document provides an overview of photosynthesis presented by a group of 6 students. It describes the key processes and phases of photosynthesis including light reaction, dark reaction, photophosphorylation, photosystems, and alternative pathways such as C4 and CAM photosynthesis. The light reaction uses energy from sunlight to split water and produce ATP and NADPH. The dark reaction then uses these products to fix carbon from carbon dioxide into sugars.
Carbon cycles between the atmosphere, organisms, oceans, and lithosphere. Plants absorb carbon dioxide from the air through photosynthesis, and animals obtain carbon by eating plants or other animals. When organisms die, decomposers release carbon back into the atmosphere or it becomes trapped underground in fossil fuels and other deposits. Human activities like burning fossil fuels have increased the amount of carbon dioxide in the atmosphere, contributing to global warming.
The document outlines the process of photosynthesis through 6 main topics: plant structure, pigments and absorbance spectrum, light-dependent reactions, Calvin cycle, and photorespiration. It discusses the key organelles and structures involved in photosynthesis in plant leaves like chloroplasts, stomata, and mesophyll tissue. It also explains the light and dark reactions of photosynthesis, including the light-dependent reaction where light energy is captured and the Calvin cycle where carbon is fixed into glucose.
2. Co je fotosyntéza?
jedinečný dej na Zemi, súbor biochemických
reakcií, při ktorom sa zachytáva energia
slnečného žiarenia. Tá sa potom využíva na
syntézu sacharidov z jednoduchých
anorganických zlúčenín (CO2 a H2O).
zároveň sa energia slnečného žiarenia
premieňa na energiu chemických väzieb.
3. Co je fotosyntéza?
Schopnosť fotosyntézy majú :
- vyššie rastliny
- zelené a hnedé riasy
- sinice
- zelené baktérie
7. Kde fotosyntéza prebieha?
V chloroplastoch sa nachádzajú tzv. fotosyntetické
(asimilačné) farbivá, ktoré zachytávajú svetelné žiarenie.
Najvýznamnejšie sú chlorofyly.
Rozonávame sedem typov chlorofylov (a, b, c, d, e).
Najvýznamnejší je chlorofyl a absorbuje oblasť svetelného
žiarenia s vlnovou dĺžkou 400 – 700 nm a chlorofyl b.
- štruktúrne sa od seba líšia len jednou funkčnou skupinou.
10. K čomu slúžia fotosyntetické pigmenty?
asimilačné pigmenty fungujú ako
„zberače“ slnečnej energie fotónov rôznej
vlnovej dĺžky,
energiu postupne prenášajú až na
konečný akceptor chlorofyl a
jedine chlorofyl a transformuje svetelnú
energiu na chemickú
11. Aké fotosyntetické pigmenty rozlišujeme?
chlorofyly – zelené farbivá
vyššie rastliny, zelené riasy: chlorofyly a, b
hnedé riasy: chlorofyly a, c
červené riasy: chlorofyly a, d
baktérie: bakteriochlorofyly a, b
karotenoidy – žltororanžové
xantofyly
karoteny
fykobiliny
fykoerytrin – červenofialový
fykocyanin – modrozelený
12. Aké je zloženie slnečného žiarnia?
fotosyntetizujúce organizmy využívajú len
viditeľnú časť spektra, tj. 400 – 700 nm
16. Svetelná (primárna) fáza fotosyntézy
dochádza k absorpcii svetelnej energie a jej premena na
energiu chemickú
prebieha na tylakoidoch chloroplastov
Uskutočňuje sa 2 fotosystémami:
Fotosystém I, kde je aktívny chlorofyl a1 s vlnovou dĺžkou
700 nm, preto sa označuje P-700
Fotosystém II, kde je aktívny chlorofyl a2 s vlnovou dĺžkou
680 nm, preto sa označuje P-680
17. Fotosytém I
Molekula P700 pohltí svetlo – prejde do excitovaného stavu a zároveň sa
výrazne zníži jej oxidačno – redukčný potenciál (P700*), tým sa z nej
stane redukovadlo, ktoré ľahko uvoľní elektrón.
18. Fotosytém I
Uvoľnený elektrón je transportovaný reťazcom bielkovinových
prenášačov (feredoxín – Fd, flavoproteín – Fp) až na koenzým NADP+
.
19. Fotosytém I
Prijatím elektrónu sa NADP+
sa redukuje na NADPH + H+
Na túto redukciu sú potrebné 2 elektróny, preto vždy vychádzame z excitácie
dvoch molekúl P700.
20. Fotosytém I
Redukovaný koenzým NADPH je jedným z konečných produktov
svetelnej fázy fotosyntézy – neskôr sa využije v tmavej fáze.
21.
22. Pôvodná molekula P700 stratila jeden elektrón, aby sa vrátila do
základného stavu, musí si chýbajúci elektrón doplniť – zdrojom je
fotosystém II.
23. Fotosytém II
Ožiarením a excitáciou molekuly P680 sa uvoľní jeden elektrón, ktorý je
transportovaný bielkovinovými prenášačmi (plastochinón – PQ,
cytochrómami a plastocyanínom – PC) až na molekulu P700.
24. Aj tu sa uvažuje o excitácii dvoch molekúl P680, teda o uvoľnení
2 elektrónov.
25. Akým spôsobom sa doplní elektrón
do P680?
doplní sa rozkladom molekuly vody účinkom
svetla - fotolýza vody:
H2O → ½ O2 + 2 H+
+ 2e-
kyslík - atmosféra
protóny – tvorba redukčného činidla
elektróny – fotosystém II
26. Fotosytém II
Pri transporte elektrónov medzi P-680 a P-700 sa tvorí ATP (dej –
fotofosforylácia). Dochádza k prenosu protónov zo stromy chloroplastov
do vnútra tylakoidov.
27. ATP je druhým konečným produktom svetelnej fázy fotosyntézy.
28. Elektróny z fotolýzy vody sa nevracajú na miesto, z ktorého
boli uvoľnené – ide preto o necyklický dej = necyklický
prenos elektrónov (necyklická fotofosforylácia).
29. 29
Aký je význam necyklickej fotofosforylácie?
tvorí sa ATP
vzniká redukčné činidlo NADPH + H+
pre
sekundárne procesy
do atmosféry se uvolňuje kyslík
ATP sa využije v tmavej fáze fotosyntézy jako zdroj energie na
tvorbu sacharidov.
NADPH + H+
– ako látka potrebná na redukciu oxidu uhličitého.
30. 30
Cyklický prenos elektrónov (cyklická fotofosforylácia)
Elektrón uvoľnený molekulou P700 sa cez feredoxín – Fd,
cytochrómy a plastocyanín – PC vracia späť na molekulu P700.
32. 32
Aký je význam cyklickej fotofosforylácie?
tvorí sa len ATP, (nevzniká ani redukovadlo
NADPH, nie je ani produkovaný kyslík)
Pri necyklickej fotofosforylácii sa vytvorí ATP a NADPH + H+
v
rovnakom množstve. Pre tmavej fáze fotosyntézy sa však
spotrebuje viac ATP jako NADPH + H+
. Cyklická
fotofosforylácia vlastne vyrovná tento rozdiel.
33. Tmavá (sekundárna) fáza fotosyntézy
nevyžaduje prítomnosť svetla = tmavá (temnostná),
syntetická fáza
dochádza k fixácii CO2 a jeho premene na sacharidy
CO2 sa redukuje, potrebná energia sa získava z ATP 0
uskutočňuje sa v stróme chloroplastov
34. Podľa priebehu sekundárnych procesov rozdeľujeme
rastliny na dve skupiny:
1. Rastliny C3
2. Rastliny C4
35. Rastliny C3
Sacharidy sa vytvárajú metabolickým reťazcom –
CALVINOV a BENSONOV cyklus
uhlík vstupuje v podobe CO2 a opúšťa ho ako glukóza
spotrebúva sa ATP ako zdroj energie a NADPH + H+
ako
zdroj vodíka
36. CALVINOV CYKLUS
primárnym akceptorom molekuly CO2 je ribulóza-1,5-
bisfosfát (RuBP).
po naviazaní sa rozpadne na dve molekuly kyseliny
3-fosfoglycerovej (s troma uhlíkmi - preto C3).
2 molekuly kyseliny 3-fosfoglycerovej sú redukované
na glyceraldehyd-3-fosfát z 1/6 molekuly sa
tvorí glukóza, zvyšných 5/6 sa obnoví na ribulózu - 1,5-
bisfosfát, ktorá sa vráti a opäť viaže CO2.
Keď tento cyklický dej prebehne šesť krát, vytvorí sa
postupne jedna molekula glukózy.
37.
38. Produkty fotosyntézy (sacharidy) bývajú u rastlín C3 z
veľkej časti (až 50 %) odbúravané už pri fotosyntéze
oxidačnými procesmi (dýchaním) za vzniku voľného
CO2 fotorespiráciou.
Medzi rastliny C3 patria všetky dvojklíčnolistové rastliny
a niektoré jednoklíčnolistové rastliny.
40. HATCHOV A SLACKOV CYKLUS
akceptorom CO2 je fosfoenolpyruvát, ktorý sa po
naviazaní mení za účasti NADPH + H+
a ATP
na oxalacetát, (má 4 uhlíky - preto C4).
Oxalacetát sa zložitými reakciami mení na glukózu a
fosfoenolpyruvát.
Rastliny C4 majú podstatne nižšiu fotorespiráciu a tým je výťažok
z fotosyntézy vyšší. Poskytujú vyššie výnosy. Patria
sem tropické trávy, kukurica, proso, bambus, cukrová trstina a
niektoré ďalšie jednoklíčnolistové rastliny.
41.
42. Účinnosť fotosyntézy závisí od činiteľov:
vlnová dĺžka a intenzita svetla – rastlina využíva len 2%
svetla, zvyšok odráža alebo prepúšťa
množstvo CO2 – v atmosfére je 0,03%. Jeho zvýšenie alebo
zníženie spomaľuje fotosyntézu. Toto má význam pri pestovaní
kultúrnych rastlín, keď napr. v skleníku je možné umelo
zvyšovať množstvo CO2 a tým ovplyvniť výnos z pestovaných
rastlín. Z 1 g CO2 sa vytvorí asi 0,5 g sušiny.
teplota – optimum sa pohybuje medzi 25 – 30°C
množstvo vody – nedostatok vody spomaľuje fotosyntézu,
pretože sa uzatvárajú prieduchy, ktorými preniká do rastliny
CO2
