action principle
Chloroplast plants are different from animals. They have no digestive system, so they must rely on other ways to absorb nutrients. Plants are one of the so-called autotrophs. For green plants, in sunny days, they use solar energy for photosynthesis to obtain nutrients necessary for growth and development. The key participant in this process is the internal chloroplast. Under the action of sunlight, chloroplasts transform carbon dioxide entering leaves through stomata and water absorbed by roots into energy substances such as starch and release oxygen at the same time.
Chemical equation CO2+H2O→(CH2O)+O2 (reaction conditions: light energy and chloroplast) 12H2O+6CO2+ sunlight → (chemical reaction with chlorophyll); C6H 12O6 (glucose)+6o2+6H2O H2O → 2h+2e-+12o2 (photolytic water) NADP+2e-+h+→ NADPH (hydrogen transfer) ADP+Pi+ energy →ATP (energy transfer) CO2+C5. 2C3 compound +4NADPH→C3 sugar (organic matter generation or C3 reduction) C3 (partial) →C5 compound (partial) glucose, sucrose, starch, and some also produce fat) ATP→ADP+Pi+ energy (energy consumption) Energy conversion process: light energy → electric energy → unstable chemical energy (energy stored in high-energy phosphate bond of ATP) → stable chemistry. In other words, the carbon reaction does not have to be carried out in the dark.
Photoreaction conditions: light, photosynthetic pigment, photoreaction enzyme. Setting: thylakoid membrane of chloroplast. Photosynthetic reaction (where the pigment is located): (raw material) light (product) water+carbon dioxide-→ organic matter (mainly starch or fat)+oxygen (light and chloroplast are conditions) Chloroplast process: ① photolysis water: 2H2O→4[H]+O2 (catalysis of pigment in light and chloroplast) ②ATP synthesis: ADP+Pi+ energy →ATP. Influencing factors: light intensity, CO2 concentration, water supply, temperature, pH value, mineral elements, etc. Significance: ① Photolysis of water produces oxygen. ② Convert light energy into chemical energy to produce ATP, which provides energy for carbon reaction. (3) Synthesis of NADPH (reduced coenzyme II) from hydrogen ions produced by water photolysis to provide reducing agent NADPH (reduced coenzyme II) for carbon reaction.
Breathing is a chemical process in which biological cells oxidize and decompose organic matter and produce energy, also called cell breathing. Whether autotrophic or not, the energy needed to complete life activities in cells comes from breathing. Mitochondria is the organelle most closely related to respiration in eukaryotic cells, and several key steps of respiration are carried out in it. Breathing is an enzymatic oxidation reaction. Although it is called oxidation reaction, it can be called respiration with or without oxygen (this is because in chemistry, the reaction process with electron transfer can be called oxidation). Breathing in the presence of oxygen is called aerobic breathing; Anaerobic reaction is called anaerobic respiration. For the same amount of organic compounds, the energy produced by anaerobic respiration is less than that produced by aerobic respiration. Aerobic respiration and anaerobic respiration are different reactions in cells and have no direct relationship with organisms. Even organisms that breathe oxygen can breathe anaerobically in cells. The purpose of breathing is to produce adenosine triphosphate (ATP) by releasing energy in food, and ATP is the most important direct energy donor for cells. The process of respiration can be compared to the combustion of hydrogen and oxygen, but the biggest difference between them is that respiration releases the energy in food step by step through a series of reaction steps, rather than releasing it at one time like combustion. During respiration, three nutrients, namely, carbohydrates, protein and basic components of lipids-glucose, amino acids and fatty acids, are broken down into smaller molecules, and energy is transferred to reduced hydrogen (hydrogen with valence of+1) through several steps. Finally, through a series of electron transfer chains, hydrogen is oxidized to generate water; The energy originally stored in it is transferred to ATP molecules for life activities.
Plant respiration process: organic matter (energy storage)+oxygen (through mitochondria) → carbon dioxide+water+energy chemical formula organic matter (energy storage) (generally glucose C6H 12O6)+6O2 → (condition: enzyme) 6CO2+6H2O+ large amount of energy anaerobic respiration chemical formula organic matter (C6h12o6).