Nutrition and Metabolism

Nutrition and Metabolism Indian Medical PG Question 1: What is the fasting blood glucose level that confirms a diagnosis of diabetes mellitus?

• A. >200
• B. <100
• C. ≥126 (Correct Answer)
• D. 101-125

Nutrition and Metabolism Explanation: ≥126 - A fasting plasma glucose (FPG) level of ≥126 mg/dL on two separate occasions is a diagnostic criterion for diabetes mellitus [1]. - This threshold indicates persistent hyperglycemia beyond what is considered normal. <100 - A fasting plasma glucose level <100 mg/dL is considered normal and does not indicate diabetes or prediabetes [1]. - This range reflects healthy glucose regulation in the body. 101-125 - A fasting plasma glucose level between 100-125 mg/dL indicates prediabetes or impaired fasting glucose (IFG) [1]. - While not diabetes, it signifies an increased risk for developing type 2 diabetes. >200 - A random plasma glucose (RPG) level >200 mg/dL with classic symptoms of diabetes (e.g., polyuria, polydipsia, unexplained weight loss) can confirm diabetes [1]. - However, for a fasting blood glucose alone to confirm diabetes, it needs to be ≥126 mg/dL, and a level >200 mg/dL would be an even more severe manifestation.

Nutrition and Metabolism Indian Medical PG Question 2: A destitute woman is admitted to the hospital with altered sensorium and dehydration; urine analysis shows mild proteinuria and no sugar; which test would be most appropriate to perform next to assess for possible ketosis?

• A. Rothera's test (for ketone bodies) (Correct Answer)
• B. Hays test (for bile salts)
• C. Fouchet's test (for bile pigments)
• D. Benedict's test (for reducing sugars)

Nutrition and Metabolism Explanation: ***Rothera's test (for ketone bodies)*** - The patient's presentation with **altered sensorium** and **dehydration**, along with absent glycosuria, strongly suggests conditions like starvation ketosis or alcoholic ketoacidosis, making a test for ketones essential. - **Rothera's test** specifically detects **acetoacetate and acetone**, key indicators of ketosis, which are important in diagnosing metabolic emergencies. *Fouchet's test (for bile pigments)* - This test is used to detect **bile pigments (bilirubin)** in urine, indicating **jaundice** or liver dysfunction. - The patient's symptoms do not specifically point towards a need for bile pigment detection. *Hays test (for bile salts)* - **Hays test** uses sulfur powder to detect **bile salts** in urine as a floating test. - Bile salts in urine suggest cholestasis or obstructive jaundice, which is not indicated by the current clinical presentation. *Benedict's test (for reducing sugars)* - **Benedict's test** is used to detect **reducing sugars** (like glucose) in urine. - The urine analysis already reported **no sugar**, making this test redundant for the current clinical context.

Nutrition and Metabolism Indian Medical PG Question 3: Which of the following will be target population for screening of diabetes?

• A. People over 40 years of age
• B. People with family history of diabetes
• C. Women who have had a baby weighing more than 4·5 kg
• D. All of the options (Correct Answer)

Nutrition and Metabolism Explanation: ***All of the options*** - All listed groups—**people over 40 years of age**, **individuals with a family history of diabetes**, and **women who have had a baby weighing more than 4.5 kg**—are considered high-risk populations for developing diabetes. - Screening these groups is a **cost-effective strategy** to identify diabetes early, allowing for timely intervention and prevention of complications. *People over 40 years of age* - **Age** is a significant risk factor for type 2 diabetes, with incidence progressively increasing after 40 due to decreased insulin sensitivity. - Routine screening is recommended by guidelines for adults in this age group, regardless of other risk factors. *People with family history of diabetes* - A **genetic predisposition** plays a crucial role in the development of type 2 diabetes, making a family history a strong indicator for increased risk. - Screening is essential for these individuals to detect the condition early, even if they are otherwise asymptomatic. *Women who have had a baby weighing more than 4·5 kg* - Delivering a **large-for-gestational-age infant** (macrosomia) is a strong indicator of prior **gestational diabetes (GDM)**, even if not formally diagnosed at the time. - Women with a history of GDM have a significantly increased risk of developing type 2 diabetes later in life.

Nutrition and Metabolism Indian Medical PG Question 4: Which of the following metabolic pathways in carbohydrate metabolism is required for the synthesis of nucleic acids?

• A. Gluconeogenesis
• B. Glycolysis
• C. HMP shunt (Correct Answer)
• D. Glycogenesis

Nutrition and Metabolism Explanation: ***HMP shunt*** - The **hexose monophosphate (HMP) shunt**, also known as the **pentose phosphate pathway**, is crucial for producing **ribose-5-phosphate**. - **Ribose-5-phosphate** is a direct precursor for the synthesis of **nucleotides** and subsequently **nucleic acids** (DNA and RNA). *Gluconeogenesis* - This pathway is responsible for the synthesis of **glucose from non-carbohydrate precursors**, primarily to maintain blood glucose levels during fasting. - It does not directly produce components needed for nucleic acid synthesis. *Glycolysis* - **Glycolysis** is the metabolic pathway that breaks down **glucose into pyruvate**, generating ATP. - While it produces intermediates, it is not directly involved in creating the specific pentose sugars required for nucleic acids. *Glycogenesis* - **Glycogenesis** is the process of synthesizing **glycogen from glucose** for storage in the liver and muscles. - This pathway is focused on glucose storage and has no direct role in nucleic acid synthesis.

Nutrition and Metabolism Indian Medical PG Question 5: Calcified canal is explored with all of the given instruments except:

• A. 10 K file (Correct Answer)
• B. 6 K file
• C. C+ file
• D. Profinder

Nutrition and Metabolism Explanation: ***10 K file*** - **#10 K-files** are typically used for initial negotiation of **larger, more accessible canals**, not for exploring highly calcified or severely constricted canals. - Their larger diameter (0.10 mm) makes them too stiff and prone to ledge formation or perforation in extremely calcified areas. *6 K file* - **#6 K-files** are extremely small and flexible (0.06 mm in diameter), making them ideal for initial penetration through tight, calcified canal orifices. - Their fine tip and flexibility help in navigating complex anatomy and overcoming initial resistance without causing iatrogenic damage. *C+ file* - **C+ files** are specifically designed for calcified or severely curved canals due to their **stiffer shaft, non-cutting tip**, and improved resistance to buckling. - They are offered in multiple diameters, including very small sizes like 06 and 08, which are suitable for initial exploration of challenging canal anatomy. *Profinder* - **ProFinder files** are specialized stainless steel hand files with a **triangular cross-section** and non-cutting tip, designed for initial negotiation of difficult and calcified canals. - Their enhanced tip design and shaft stiffness facilitate easy insertion into tight orifices and help maintain the canal pathway.

Nutrition and Metabolism Indian Medical PG Question 6: Which of the following is active in dephosphorylated state?

• A. PEPCK
• B. Pyruvate Carboxylase
• C. Glycogen Synthase (Correct Answer)
• D. Glycogen Phosphorylase

Nutrition and Metabolism Explanation: ***Glycogen Synthase*** - **Glycogen synthase** is primarily active in its **dephosphorylated state**, which is promoted by insulin and signals glycogen synthesis. - Dephosphorylation relieves the inhibitory effect of phosphorylation, allowing the enzyme to efficiently add glucose units to a **growing glycogen chain**. *PEPCK* - **Phosphoenolpyruvate carboxykinase (PEPCK)** activity is primarily regulated at the transcriptional level, not typically by phosphorylation state for activation. - Its expression is induced by **glucagon** and **cortisol** during gluconeogenesis. *Pyruvate Carboxylase* - **Pyruvate carboxylase** is allosterically activated by **acetyl-CoA** and its activity is not directly regulated by phosphorylation/dephosphorylation in the same manner as glycogen synthase. - This enzyme plays a key role in **gluconeogenesis** by converting pyruvate to oxaloacetate. *Glycogen Phosphorylase* - **Glycogen phosphorylase** is active in its **phosphorylated state**, particularly the 'a' form, which is promoted by glucagon and adrenaline for glycogen breakdown. - Phosphorylation activates the enzyme, leading to the **breakdown of glycogen** into glucose-1-phosphate.

Nutrition and Metabolism Indian Medical PG Question 7: Semantic memory includes all except:

• A. Rules
• B. Language
• C. Events (Correct Answer)
• D. Words

Nutrition and Metabolism Explanation: ***Events*** - **Episodic memory** is the type of long-term memory that stores information about specific **personal events** and experiences, complete with their contextual details like time and place. - Semantic memory, in contrast, involves general facts and knowledge, decoupled from specific personal experiences. *Rules* - **Semantic memory** encompasses our understanding of operating principles and **general truths**, such as the laws of physics or social conventions. - This abstract knowledge about how things work or are structured is a core component of semantic memory. *Language* - The understanding of **vocabulary**, **grammar**, and syntax necessary for communication is a key aspect of semantic memory. - This includes knowledge of word meanings, relationships between words, and how to construct grammatically correct sentences. *Words* - The meaning and definition of individual **words** are stored within **semantic memory**. - This allows us to comprehend spoken and written language and to use words appropriately in context.

Nutrition and Metabolism Indian Medical PG Question 8: An obese patient presented in casualty in an unconscious state, with a blood glucose level of 400 mg/dL and urine testing positive for sugar and ketones. Which drug is most useful in his management?

• A. Glibenclamide
• B. Troglitazone
• C. Insulin (Correct Answer)
• D. Chlorpropamide

Nutrition and Metabolism Explanation: Insulin - The patient presents with **hyperglycemia**, **ketonuria**, and an **unconscious state**, suggestive of **diabetic ketoacidosis (DKA)** or at least severe uncontrolled diabetes requiring urgent glucose management [1], [4]. - **Insulin therapy** is crucial for DKA management, as it lowers blood glucose, resolves ketosis, and helps correct electrolyte imbalances [3]. *Glibenclamide* - This is a **sulfonylurea** that stimulates insulin release from pancreatic beta cells. - It is **contraindicated in DKA** because the pancreas is often severely stressed or non-functional, and it can worsen hypoglycemia if given inappropriately [2]. *Troglitazone* - This is a **thiazolidinedione** (glitazone) which improves insulin sensitivity in peripheral tissues. - It is **not used for acute hyperglycemia or DKA** and was withdrawn from the market due to liver toxicity. *Chlorpropamide* - This is an older **first-generation sulfonylurea**, similar to glibenclamide, that stimulates insulin secretion. - It has a **long half-life** and a higher risk of **hypoglycemia**, making it unsuitable for acute, severe hyperglycemia like DKA [2].

Nutrition and Metabolism Indian Medical PG Question 9: A person switches from a high-fat diet to a low-fat diet with a compensatory increase in carbohydrates to maintain the same caloric intake. Which lipoprotein is likely to increase?

• A. Chylomicron
• B. IDL
• C. HDL
• D. VLDL (Correct Answer)

Nutrition and Metabolism Explanation: ***VLDL*** - A low-fat diet with increased **carbohydrates** can lead to increased hepatic synthesis of triglycerides, which are then packaged into **VLDL** particles for transport from the liver. This is because excess carbohydrates can be converted to fatty acids and then to triglycerides in the liver. - The liver's increased triglyceride production, driven by abundant **glucose** from carbohydrates, directly corresponds to a rise in **VLDL** secretion to export these lipids. *Chylomicron* - **Chylomicrons** primarily transport **dietary fats** (exogenous triglycerides) absorbed from the intestine. - Switching to a low-fat diet would typically lead to a *decrease* in chylomicron production, as less dietary fat is available for absorption. *IDL* - **IDL** (Intermediate-Density Lipoprotein) is a remnant of **VLDL** metabolism, formed after VLDL loses some triglycerides. - While VLDL may increase, leading to *more* IDL formation, IDL itself is not the primary component that *increases* directly due to high carbohydrate intake; rather, the precursor **VLDL** is directly affected. *HDL* - **HDL** (High-Density Lipoprotein) is involved in **reverse cholesterol transport**, picking up excess cholesterol from peripheral tissues and returning it to the liver. - High carbohydrate intake, especially refined carbohydrates, can sometimes lead to a *decrease* in HDL levels, not an increase.

Nutrition and Metabolism Indian Medical PG Question 10: An infant presents with failure to thrive and recurrent vomiting episodes. Sepsis screen was negative, blood urea is elevated and urine shows high orotic acid level. Which of the following enzyme is absent?

• A. 1
• B. 2
• C. 3 (Correct Answer)
• D. 4

Nutrition and Metabolism Explanation: ***Correct Option 3 (Ornithine Transcarbamylase)*** - The presence of **elevated urine orotic acid** is pathognomonic for **ornithine transcarbamylase (OTC) deficiency**. - This occurs because carbamoyl phosphate accumulates in mitochondria when it cannot be converted to citrulline, then leaks into the cytoplasm where it enters the **pyrimidine synthesis pathway**, producing orotic acid. - The elevated blood urea indicates hyperammonemia, and the clinical picture of failure to thrive with recurrent vomiting is classic for OTC deficiency. - **OTC deficiency is the only urea cycle disorder that causes orotic aciduria** because the block occurs after carbamoyl phosphate formation but before citrulline synthesis. *Incorrect Option 1 (N-acetylglutamate synthase)* - N-acetylglutamate synthase produces N-acetylglutamate, which is an **allosteric activator of carbamoyl phosphate synthetase I (CPS1)**. - Deficiency here would impair CPS1 activity, leading to **decreased carbamoyl phosphate formation**. - This would cause hyperammonemia but **not orotic aciduria**, as insufficient carbamoyl phosphate would be available to shunt into pyrimidine synthesis. *Incorrect Option 2 (Carbamoyl Phosphate Synthetase I)* - CPS1 deficiency prevents formation of carbamoyl phosphate from ammonia and CO₂. - This causes severe hyperammonemia with very low or absent carbamoyl phosphate levels. - **No orotic aciduria occurs** because the substrate (carbamoyl phosphate) needed for pyrimidine synthesis is not produced. *Incorrect Option 4 (Downstream urea cycle enzymes)* - Later enzymes in the cycle include argininosuccinate synthetase and argininosuccinate lyase. - Deficiencies cause accumulation of citrulline or argininosuccinate respectively, with hyperammonemia. - **No orotic aciduria occurs** because carbamoyl phosphate is successfully converted to citrulline and doesn't accumulate to shunt into pyrimidine synthesis.

Nutrition and Metabolism Flashcard 1 of 10

Question: Each cycle of MMC consists of _____ phases

Answer: 3

Nutrition and Metabolism Flashcard 2 of 10

Question: Correct sequence of specific dynamic values (SDA) of proteins _____ lipids > carbohydrates.

Answer: >

Nutrition and Metabolism Flashcard 3 of 10

Question: _____ score is the best indicator of protein quality*calculated by?

Answer: Digestible indispensable amino acid

Nutrition and Metabolism Flashcard 4 of 10

Question: _____ deficiency presents with hypercholesterolemia and weight loss

Answer: Manganese

Nutrition and Metabolism Flashcard 5 of 10

Question: Starter F75 has 75 kcal and _____ g protein per 100 mL

Answer: 0.9

Nutrition and Metabolism Flashcard 6 of 10

Question: 1. Identify → _____ 2. Nutritional values → _____

Answer: Soyabean

Extra Information: 

Nutrition and Metabolism Flashcard 7 of 10

Question: _____ is an internal protein indicator

Answer: BV(biological value)

Extra Information: 

Nutrition and Metabolism Flashcard 8 of 10

Question: _____ has the maximum NPU(net protein utilisation)

Answer: egg

Extra Information: 

Nutrition and Metabolism Flashcard 9 of 10

Question: _____ is the best protein indicator

Answer: digestible indispensable amino acid score(DIAAS)

Extra Information: 

Nutrition and Metabolism Flashcard 10 of 10

Question: b1172ab22c5a40b4808b1a321f9bac0e-ao-19

Answer: RDA(recommended daily allowance)

Extra Information: IRON IN PREGNANCY IS 27 MG/DAY