Enzymes Enzyme are partly or entirely a protein that can tremendously increase the efficiency of a biochemical reaction and is generally specific for that reaction. The term enzyme (Gr. en = in + zyme = living) was first discovered by W. Kuhne in 1878 while working on fermentation. Nature of Enzymes – Physical Properties The enzymes are proteins wholly or partly. ...
Read More »Biochemistry of Biological Nitrogen Fixation
Biochemistry of Biological Nitrogen Fixation Nitrogen fixing bacteria that occur in association with higher plants, especially with those of family Leguminaceae (fabaceae), are termed as symbionts. The symbiotic association of nitrogen-fixing bacteria with plants roots generally occurs in multicellular structures called nodules. The best characterized symbiotic association involving nodules is one occurring on roots of leguminous plants. About 200 legume ...
Read More »Nitrogen Cycle
Nitrogen Metabolism Nutrient Assimilation Higher plants are autotrophic organisms that can synthesize all of their molecular components from inorganic nutrients from the local environment. The mineral nutrients taken up by plants are converted into carbohydrates, lipids and amino acids. It is called nutrient assimilation. Nitrogen Assimilation Nitrogen is a key element in many of the compounds present in the plants. ...
Read More »Oxidative Phosphorylation
Oxidative Phosphorylation – ATP Synthesis Oxidative phosphorylation occurs in mitochondria here transfer of electrons is coupled with ATP formation from ADP and Pi. It is driven by the strong thermodynamics tendency of O2 to become reduced, therefore, called oxidative phosphorylation. Oxidative phosphorylation accounts for only a small fraction of ATP generated in living cells of higher plants. The number of ...
Read More »Electron Transport Chain
Respiratory Chain When NADH2 and FADH2 are produced in the Krebs cycle or in glycolysis are oxidized, ATP is produced. The electrons are transferred via several intermediate compounds before water is made. These electron carriers constitute electron transport system or respiratory chain. Components of Electron Transport System An electron system consists of: Cytochromes, four of the b type and two ...
Read More »krebs cycle
Krebs Cycle Hans A. Krebs first proposed a series of breakdown of pyruvate in the presence of oxygen, therefore the cycle is called Krebs Cycle. The cycle is also called citric acid cycle because formation of an important intermediate citric acid. krebs cycle takes place in the matrix of mitochondria. Entry of Pyruvate in to Mitochondria The pyruvate produced in the ...
Read More »Mechanism Of Respiration
Mechanism Of Respiration Respiration suggests that respiration is multi-step process in which glucose is oxidized during a series of reactions. These reactions can be subdivided into three stages: Glycolysis It is carried out by a group of soluble enzymes located in the cytosol (liquid part of cytoplasm). Chemically, the glucose undergoes a limited amount of oxidation to produce two molecules ...
Read More »What Are Plastids
Plastids The membranous bound and pigment containing bodies present in the cell are called plastids. Plastids were Discovered by Schimper in 1883. Plastids are present only in plant cells and some algae. Plastids are semi-autonomous bodies of cells. They contain their own DNA and ribosome. So, they are self-replicating organelles. The newly form plastid is called protoplastid. It then changes into ...
Read More »Fermentation
The respiration which happens without oxygen is called anaerobic respiration. There are two perspectives about the source of fermentation: (an) It is a developmental sidestep. A few life forms use to hold glycolysis working under anaerobic conditions. (b) It is a biochemical remainder. It has developed right on time in the history of life. Around then the world’s environment contained ...
Read More »Respiration In Plants
Respiration Tissue Respiration Respiration is a series of enzyme controlled oxidation-reduction reactions during which carbohydrates (respiratory substrate) produced during photosynthesis are oxidized to carbon dioxide and oxygen is reduced to water. Energy is released as a result of bond by bond breakage of respiratory substrate. Much of this energy is stored into molecules of adenosine triphosphate (ATP). The process is ...
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