Table of Contents
- 1 Why is the pentose phosphate pathway?
- 2 Does the pentose phosphate pathway occur in the brain?
- 3 What are the two main functions of pentose phosphate pathway?
- 4 Where does HMP shunt occurs?
- 5 How is pentose phosphate pathway regulated?
- 6 What activates the pentose phosphate pathway?
- 7 What regulates the pentose phosphate pathway?
- 8 How is the pentose phosphate pathway controlled?
- 9 Where does photosynthesis and cellular respiration occur?
- 10 Where does telophase occur?
Why is the pentose phosphate pathway?
The pentose phosphate pathway meets the need of all organisms for a source of nicotinamide adenine dinucleotide phosphate (NADPH) to use in reductive biosynthesis, such as fatty acid, cholesterol, neurotransmitter, and nucleotide biosynthesis, and synthesizes five-carbon sugars (Figure 1).
Does the pentose phosphate pathway occur in the brain?
The pentose phosphate pathway (PPP) is an essential metabolic pathway in the glucose metabolism of the brain. However, its products NADPH and ribose-5-phosphate have important functions in brain cells as electron donor for various enzymatic reactions and as precursor for the synthesis of nucleotides, respectively.
Does pentose phosphate pathway occur in muscle?
DIRECT oxidation of glucose-6-phosphate through the pentose phosphate pathway is known to occur in various animal tissues. The activity of these enzymes in skeletal muscle is exceptionally low compared with that of most other mammalian tissues studied1.
What are the two main functions of pentose phosphate pathway?
The pentose phosphate shunt pathway (Fig. 3.6) has two major roles: provision of NADPH that is utilized in biosynthetic reactions and oxidative defense, and generation of 5-carbon intermediates that are precursors for nucleic acids (Dringen et al., 2007).
Where does HMP shunt occurs?
The hexose monophosphate shunt (HMP) is also called the pentose phosphate pathway. It occurs in the cytoplasm and is a major source of NADPH and 5-carbon sugars. The HMP consists of two irreversible oxidative reactions and a series of reversible sugar-phosphate conversions. No ATP is consumed or produced directly.
What inhibits the pentose phosphate pathway?
Dichloroacetate (DCA) is a pyruvate dehydrogenase kinase (PDK) inhibitor. 6-aminonicotinamide (6-AN) is an inhibitor of NADP+-dependent enzymes of the pentose phosphate pathway, glucose-6-phosphate dehydrogenase (G6PD) and 6-phosphogluconate dehydrogenase (6-PGD). All chemicals were purchased from Sigma.
How is pentose phosphate pathway regulated?
The regulation of the pentose phosphate pathway is at the level of its first enzyme, namely, glucose-6-phosphate dehydrogenase, which is controlled by the redox state of the NADP couple, NADPH having a powerful feedback inhibition on this enzyme.
What activates the pentose phosphate pathway?
Treatment of plant tissues with methylene blue and nitrate, which accepts electrons from NADPH stimulates the oxidative pentose phosphate pathway. The ratio of NADPH/NADP+ appears to be the principal factor regulating the flux through the pentose phosphate pathway.
What is the main source of glucose carbons for gluconeogenesis?
What is the main source of glucose carbons for gluconeogenesis? Explanation: The main source of glucose carbons for gluconeogenesis is alanine derived from the breakdown of muscle proteins.
What regulates the pentose phosphate pathway?
How is the pentose phosphate pathway controlled?
Where does EMP pathway occur?
The curved, bold line near the top of the figure represents the cytoplasmic membrane; reactions above that curved line occur in the periplasm, those beneath it occur in the cytoplasm. The EMP pathway is present in organisms from every branch of the bacteria, archaea, and eukarya.
Where does photosynthesis and cellular respiration occur?
Cellular respiration occurs at all times. Photosynthesis takes place in plant leaves containing the chlorophyll pigment. Cellular respiration takes place in the cytoplasm and mitochondria of the cell. Photosynthesis utilizes sunlight to produce food molecules.
Where does telophase occur?
Telophase (from the Greek τέλος (télos), “end” and φάσις (phásis), “stage”) is the final stage in both meiosis and mitosis in a eukaryotic cell.
Where does the phosphorus cycle begin?
The phosphorus cycle begins its journey in the crust of the Earth, as phosphorous is found in rocks. Weathering causes it to break free from the rocks and wash away into the ground. At this time, the phosphorus gets mixed in the soil. Land plants are now able to soak up the phosphorus from the ground.