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Describe briefly the signs and symptoms of SCID

Describe Briefly the Signs and Symptoms of SCID Severe Combined Immunodeficiency (SCID) is a group of rare genetic disorders characterized by profound defects in both humoral (B-cell) and cellular (T-cell) immunity. It is often termed as “bubble boy disease” due to the extreme measures required to protect affected individuals from infections. Causes Mutations in genes […]

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Compare catabolism of purine and pyrimidine nucleotides

Compare Catabolism of Purine and Pyrimidine Nucleotides The catabolism of purine and pyrimidine nucleotides follows distinct biochemical pathways due to structural differences in their rings. Here is a comparative overview: 1. Structural Differences Purines have a double-ring structure (adenine, guanine) Pyrimidines have a single-ring structure (cytosine, uracil, thymine) 2. End Products Purine catabolism leads to

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Elaborate on the fate of uric acid in the degradation of purine nucleotides

Elaborate on the Fate of Uric Acid in the Degradation of Purine Nucleotides Uric acid is the final product of purine nucleotide degradation in humans and other primates. Unlike many other mammals, humans lack the enzyme uricase, which converts uric acid into the more soluble allantoin. This makes uric acid excretion crucial in maintaining nitrogen

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Enlist any two inhibitors of nucleotide synthesis with their mechanism of action, enzyme inhibited and their use in medicine

Enlist Any Two Inhibitors of Nucleotide Synthesis With Their Mechanism of Action, Enzyme Inhibited, and Their Use in Medicine Nucleotide synthesis inhibitors are crucial in medicine, particularly in cancer therapy, autoimmune diseases, and transplant medicine. Here are two well-known inhibitors: 1. Methotrexate Mechanism of Action: Methotrexate is a folate analog that inhibits dihydrofolate reductase (DHFR),

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Explain the structure of type I RNR

Explain the Structure of Type I RNR Ribonucleotide reductase (RNR) is an essential enzyme responsible for reducing ribonucleotides into deoxyribonucleotides, which are the building blocks of DNA. Type I RNR is the most studied form and is found in many organisms, including bacteria and eukaryotes. Subunit Composition Large Subunit (R1 or α-subunit): Contains the catalytic

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How purine synthesis is regulated?

How Purine Synthesis is Regulated? Purine nucleotide synthesis is tightly regulated to ensure a balanced supply of purines for DNA, RNA, and energy metabolism. The regulatory mechanisms maintain the correct levels of adenine (AMP) and guanine (GMP) nucleotides while avoiding excess buildup that could be wasteful or toxic. Key Regulatory Points in Purine Synthesis 1.

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Explain de novo synthesis of UMP. Describe the steps

Explain De Novo Synthesis of UMP. Describe the Steps Uridine monophosphate (UMP) is a pyrimidine nucleotide that plays a fundamental role in RNA synthesis. In cells, UMP can be synthesized by the de novo pathway from basic precursor molecules including glutamine, aspartate, and bicarbonate. This pathway does not require preformed bases but builds the pyrimidine

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What are catecholamines?

What Are Catecholamines? Catecholamines are a group of chemically related neurotransmitters and hormones that are derived from the amino acid tyrosine. The primary catecholamines are dopamine, norepinephrine (noradrenaline), and epinephrine (adrenaline). Biosynthesis The synthesis of catecholamines occurs mainly in the adrenal medulla and the central nervous system. The pathway involves the following steps: Tyrosine →

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Describe biosynthesis of non essential amino acids of aromatic amino acid family

Describe Biosynthesis of Non-Essential Amino Acids of Aromatic Amino Acid Family The aromatic amino acid family primarily includes phenylalanine, tyrosine, and tryptophan. Among them, tyrosine is considered non-essential because it can be synthesized from phenylalanine in humans. Tryptophan and phenylalanine are essential and must be obtained from the diet. 1. Tyrosine Biosynthesis Tyrosine is synthesized

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Explain the following disorders of amino acid metabolism: Homocystinuria and Hartnup disease

Explain the Following Disorders of Amino Acid Metabolism: Homocystinuria and Hartnup Disease a) Homocystinuria Homocystinuria is an inherited disorder caused by a deficiency in the enzyme cystathionine beta-synthase (CBS), which leads to the accumulation of homocysteine and methionine in the blood and urine. This disorder is typically inherited in an autosomal recessive pattern. Causes and

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