Question 1

What are Vitamins?

Accepted Answer

Answer reason: Vitamins are organic compounds required in small amounts to support normal metabolism, growth, and physiologic functions. Most cannot be synthesized in sufficient quantities by the human body and therefore must be obtained from the diet. They act mainly as coenzymes or regulatory molecules rather than providing energy. Hence, they are classified as organic compounds, not inorganic substances, organisms, or cells.
Category reason: This question tests the basic chemical nature/definition of vitamins (organic micronutrients) rather than a nursing intervention or clinical decision, which places it in foundational biomedical science—Biochemistry.

Question 2

Deficiency of following vitamin decreases hemoglobin production?

Accepted Answer

Answer reason: Pyridoxine (vitamin B6) is a required cofactor for δ-aminolevulinic acid (ALA) synthase, the rate-limiting enzyme in heme synthesis. Reduced heme synthesis limits hemoglobin formation and can cause sideroblastic/microcytic anemia. The other listed B vitamins are not primary cofactors in heme synthesis (e.g., biotin for carboxylation reactions; thiamine for oxidative decarboxylation; niacin as NAD/NADP). Therefore B6 deficiency most directly decreases hemoglobin production.
Category reason: The question tests a biochemical cofactor role of a vitamin in heme/hemoglobin synthesis, which is a foundational metabolism concept rather than a nursing intervention or safety decision.

Question 3

Deficiency of vitamin k leads to?

Accepted Answer

Answer reason: Vitamin K is required for hepatic gamma-carboxylation of several coagulation factors (notably II, VII, IX, X) and proteins C and S, enabling normal clot formation. Deficiency therefore causes impaired coagulation with increased bleeding tendency and prolonged PT/INR. Beriberi is due to thiamine (B1) deficiency, pellagra due to niacin (B3) deficiency, and marasmus is severe calorie/protein-energy malnutrition rather than a single vitamin deficiency.
Category reason: This is a foundational question about the biochemical role of a vitamin in coagulation factor activation, which fits best under Biochemistry rather than nursing interventions or clinical management.

Question 4

One of the following statements is not true about enzymes?

Accepted Answer

Answer reason: Enzymes are typically proteins (with some RNA exceptions) and are highly specific in the reactions they catalyze. Many enzymes require cofactors/coenzymes (e.g., metal ions or vitamin-derived coenzymes) to function optimally. High temperatures generally denature enzymes by disrupting their tertiary structure, reducing or eliminating catalytic activity, so the statement that they can withstand high temperature is not true.
Category reason: This question tests foundational properties of enzymes (protein nature, specificity, cofactors, heat denaturation), which is core enzyme chemistry taught in Biochemistry rather than a nursing care decision-making scenario.

Question 5

Vitamin C is also known as?

Accepted Answer

Answer reason: Vitamin C is the common name for ascorbic acid, a water-soluble vitamin that functions as an antioxidant and is essential for collagen synthesis. Thiamine is vitamin B1, riboflavin is vitamin B2, and pantothenic acid is vitamin B5, so these are not synonyms for vitamin C. Therefore, the correct choice is ascorbic acid.
Category reason: The question tests the chemical/alternate name of a vitamin, which is a foundational nutrient/biomolecule identification concept typically covered under biochemistry.

Question 6

Which of the following plays the role of regulating solubility and dyeing properties in a dye molecule?

Accepted Answer

Answer reason: Auxochromes are substituent groups (e.g., –OH, –NH2, –SO3H, –COOH) attached to a chromophore that modify the dye’s properties by increasing solubility and enhancing affinity/binding to fibers (dyeing properties). Chromophores primarily confer color by absorbing visible light, while chromogens relate to the basic color-bearing structure. Mordants are external substances (often metal salts) used to fix dyes to fabrics rather than intrinsic groups regulating solubility within the dye molecule.
Category reason: The item tests chemical/biochemical concepts about functional groups in dye molecules (chromophore vs auxochrome and their effects on solubility and binding), which is foundational biochemistry rather than nursing care decision-making.

Question 7

What is the main structural component of plant cell walls?

Accepted Answer

Answer reason: Cellulose is the primary structural polysaccharide of plant cell walls, forming strong microfibrils that provide rigidity and shape. Starch is a storage carbohydrate in plants (e.g., in plastids) rather than a wall component. Glycogen is the main storage polysaccharide in animals and fungi, not plants.
Category reason: This question tests knowledge of biological macromolecules (polysaccharides) and their structural vs storage roles, which is primarily a Biochemistry concept.

Question 8

What is the chemical formular of benzene?

Accepted Answer

Answer reason: Benzene is an aromatic hydrocarbon consisting of a six-carbon ring with one hydrogen attached to each carbon, giving the molecular formula C6H6. The option C6H5 represents a phenyl group (benzene ring as a substituent) rather than benzene itself. C5H6 is not benzene and does not match the six-carbon aromatic structure.
Category reason: This question tests knowledge of a basic molecular (chemical) formula, which is foundational chemistry/biochemistry rather than clinical nursing decision-making.

Question 9

In female, there is abnormal metabolism of amino acid. Which of the following amino acid will appear in urine?

Accepted Answer

Answer reason: The question most classically refers to Hartnup disease, an inherited disorder of neutral amino acid transport causing defective absorption/reabsorption of tryptophan. As a result, neutral amino acids—especially tryptophan—are lost in the urine (aminoaciduria). The decreased tryptophan also reduces niacin (NAD/NADP) synthesis and can lead to pellagra-like features. Among the options, tryptophan best matches the amino acid expected to appear in urine in this context.
Category reason: This item tests understanding of amino acid metabolism/transport disorders and their biochemical consequences (aminoaciduria), which is a core topic in Biochemistry rather than nursing care decision-making.

Question 10

Which of the following is a non-reducing disaccharide?

Accepted Answer

Answer reason: Sucrose is a non-reducing disaccharide because both anomeric carbons (from glucose and fructose) are involved in the glycosidic bond, leaving no free hemiacetal/hemiketal group to act as a reducing agent. In contrast, lactose, maltose, and cellobiose each have a free anomeric carbon on one monosaccharide unit, making them reducing sugars. Therefore, sucrose is the only non-reducing disaccharide among the options.
Category reason: The question tests chemical properties of carbohydrates (reducing vs non-reducing sugars) based on glycosidic bonding and functional groups, which is core Biochemistry content rather than nursing care decision-making.

Question 11

Fats are also called?

Accepted Answer

Answer reason: In biochemistry, fats are classified as lipids, a broad group of hydrophobic molecules that includes triglycerides, phospholipids, and sterols. Dietary fats are primarily triglycerides and serve as a concentrated energy source and as components of cell membranes. Proteins and enzymes are amino-acid based molecules, and hormones are signaling molecules (some of which are lipids), but they are not the general term for fats.
Category reason: The question asks for the biochemical classification/terminology of fats, which is a foundational macromolecule concept studied in biochemistry rather than a nursing care decision.

Question 12

Which process uses mRNA to make protein at ribosomes?

Accepted Answer

Answer reason: Translation is the process in which ribosomes read the codons on mRNA and, with the help of tRNA, assemble amino acids into a polypeptide (protein). Replication copies DNA into DNA, and transcription synthesizes RNA (including mRNA) from a DNA template. Cell fractionation is a laboratory technique to separate cellular components and is not involved in protein synthesis.
Category reason: The item tests the central dogma step converting mRNA into protein at ribosomes, which is a foundational molecular biology/biochemistry concept rather than a nursing clinical decision.

Question 13

Q. What is the Chemical name of vitamin-A...?

Accepted Answer

Answer reason: Vitamin A’s chemical name is retinol, a fat-soluble retinoid important for vision (rhodopsin formation), epithelial integrity, and immune function. Thiamine is vitamin B1, calciferol refers to vitamin D, and ascorbic acid is vitamin C. Therefore, the correct option is retinol.
Category reason: The question tests the chemical/biochemical nomenclature of vitamins (vitamin A = retinol), which is a foundational biochemistry concept rather than a nursing intervention or patient-care decision.

Question 14

How many numbers of hydrogen bond formed by a water molecules?

Accepted Answer

Answer reason: A single water molecule can form up to 4 hydrogen bonds: it can donate 2 hydrogen bonds via its two hydrogen atoms and accept 2 hydrogen bonds via the two lone pairs on oxygen. This tetrahedral bonding capacity explains many of water’s properties such as high boiling point and strong cohesion. Therefore, the maximum number of hydrogen bonds formed by one water molecule is 4.
Category reason: The question tests molecular bonding capacity (hydrogen bonding) and electron lone-pair/donor-acceptor concepts, which are core topics in Biochemistry rather than patient-care decision-making.

Question 15

Chemical formula of water is ?

Accepted Answer

Answer reason: Water consists of two hydrogen atoms covalently bonded to one oxygen atom, so its molecular formula is H2O. H2O2 is hydrogen peroxide, a different compound with two oxygen atoms. O2 is elemental oxygen gas, and OH represents the hydroxyl group/ion rather than a neutral water molecule. Therefore, the correct formula for water is H2O.
Category reason: This question tests recognition of a basic chemical formula and composition of a common molecule, which is foundational chemistry/biochemistry knowledge rather than a nursing care decision.

Question 16

Most abundant organic compound on earth is____.

Accepted Answer

Answer reason: Cellulose is the most abundant organic polymer on Earth, forming the structural component of plant cell walls. Because plants comprise a large proportion of global biomass, cellulose production is extremely high. Proteins, lipids, and steroids are abundant in organisms but do not match cellulose in total global mass. Therefore, the best answer is cellulose.
Category reason: The item tests knowledge of major biomolecules and their relative abundance in nature, which is a core biochemistry concept rather than a nursing care decision.

Question 17

Lipids act as:

Accepted Answer

Answer reason: Lipids function as long-term energy storage primarily in the form of triglycerides. They also provide thermal insulation and cushioning as adipose tissue. In addition, several hormones are lipid-derived, especially steroid hormones synthesized from cholesterol. Therefore, all listed functions are correct.
Category reason: This question tests core biomolecule functions (energy storage, insulation, and lipid-derived hormones), which is foundational biochemistry rather than nursing care decision-making.

Question 18

Sugar present in DNA is......?

Accepted Answer

Answer reason: DNA contains the pentose sugar 2-deoxyribose, which lacks an -OH group at the 2' carbon compared with ribose. This structural difference helps distinguish DNA from RNA, which contains ribose. Therefore, among the options, deoxyribose is the correct sugar present in DNA.
Category reason: The question tests foundational chemical composition of nucleic acids (DNA vs RNA sugars), which is a core topic in biochemistry rather than a nursing care decision.

Question 19

Enzymes are -?

Accepted Answer

Answer reason: Enzymes are biological catalysts that accelerate biochemical reactions by lowering activation energy. In humans, the vast majority of enzymes are proteins composed of amino acids folded into specific shapes that create active sites for substrates. While some RNA molecules can act as catalysts (ribozymes), they are exceptions and not among the listed options. Therefore, the best answer is proteins.
Category reason: This question tests the chemical nature of enzymes as biomolecules, which is a core concept in biochemistry rather than nursing interventions or clinical decision-making.

Question 20

During glycolysis, one molecule of glucose produces how many ATP (net)?

Accepted Answer

Answer reason: In glycolysis, 2 ATP are invested in the early steps and 4 ATP are generated later via substrate-level phosphorylation, yielding a net gain of 2 ATP per glucose. Although glycolysis also produces 2 NADH, these are not counted as ATP in the net ATP figure for glycolysis itself. Therefore, the correct net ATP produced directly during glycolysis is 2.
Category reason: This question tests a core biochemical fact about ATP yield from the glycolytic pathway, which is foundational metabolism content rather than a nursing care decision.

Question 21

Q. Enzymes are chemically...?

Accepted Answer

Answer reason: Most enzymes are proteins (polypeptides) whose three-dimensional structure forms an active site that catalyzes biochemical reactions by lowering activation energy. While a few catalytic molecules are RNA (ribozymes), the standard and overwhelmingly common chemical nature of enzymes in humans is protein. Lipids and carbohydrates do not generally serve as biological catalysts, and “acid” is not a chemical class for enzymes.
Category reason: The question asks for the chemical nature of enzymes, a foundational concept about biomolecules and catalysis, which is part of Biochemistry rather than nursing care decision-making.

Question 22

Glucose is also called?

Accepted Answer

Answer reason: Glucose is the primary monosaccharide circulating in the bloodstream and is commonly referred to as “blood sugar” in clinical and everyday language. “Milk sugar” refers to lactose, “fruit sugar” commonly refers to fructose, and “cane sugar” refers to sucrose. Therefore, the best match for glucose is blood sugar.
Category reason: This question tests identification of common names and chemical identity of sugars (glucose vs lactose/fructose/sucrose), which is a foundational biochemistry concept rather than a nursing care decision.

Question 23

Cell wall in plants cell is made up of..?

Accepted Answer

Answer reason: Plant cell walls are primarily composed of cellulose, a structural polysaccharide made of long chains of β(1→4)-linked glucose that provides rigidity and strength. Sucrose is a transport and storage disaccharide in plants, not a structural wall component. Fructose is a monosaccharide found in fruits and other plant tissues but does not form the main structural framework of the cell wall. Therefore, cellulose is the best answer.
Category reason: This question tests the chemical composition of a biological structure (plant cell wall) and focuses on biomolecules (polysaccharides) rather than clinical nursing care, aligning best with Biochemistry.

Question 24

Starch is a?

Accepted Answer

Answer reason: Starch is a storage carbohydrate in plants made up of many glucose units linked together, mainly as amylose and amylopectin. Because it consists of long chains (polymers) of monosaccharides, it is classified as a polysaccharide. Monosaccharides are single sugar units (e.g., glucose) and disaccharides are two-unit sugars (e.g., sucrose), which do not describe starch. Protein is a different macromolecule composed of amino acids, not sugars.
Category reason: This item tests classification of carbohydrates based on their chemical structure and polymer length, which is core content in biochemistry.

Question 25

Glycolysis occurs in the:

Accepted Answer

Answer reason: Glycolysis is the cytoplasmic pathway that converts glucose to pyruvate and generates a net yield of ATP and NADH. It occurs in the cytosol and does not require mitochondria or oxygen. In contrast, the citric acid (TCA) cycle and oxidative phosphorylation occur in mitochondria. The nucleus and ribosomes are not sites of glucose breakdown for ATP production.
Category reason: This question tests the cellular location of a core metabolic pathway (glycolysis), which is a foundational concept in biochemistry rather than a nursing intervention or patient-care decision.

Question 26

What is the mass of 1 mole of H2 gas?

Accepted Answer

Answer reason: The molar mass of hydrogen (H) is approximately 1 g/mol. A molecule of hydrogen gas is H2, meaning it contains two hydrogen atoms, so its molar mass is about 2 g/mol. Therefore, 1 mole of H2 gas has a mass of 2 g. The other options correspond to incorrect atom counts or arithmetic.
Category reason: This question tests calculation of molar mass based on atomic mass and molecular formula, which is core chemical knowledge relevant to biochemistry foundations rather than nursing care decisions.

Question 27

How many amino acids make up a protein?

Accepted Answer

Answer reason: Proteins are polymers built from the 20 standard (proteinogenic) amino acids encoded by the genetic code and incorporated during translation. While additional amino acids like selenocysteine and pyrrolysine can occur in some organisms, the core set used to build proteins is classically taught as 20. Therefore, among the options provided, 20 is the best answer.
Category reason: The question tests foundational knowledge about the standard amino acids used to build proteins, which is a core topic in biochemical structure and macromolecules.

Question 28

Which term refers to a solution with a high pH?

Accepted Answer

Answer reason: A high pH indicates a low concentration of hydrogen ions (H+), which characterizes a basic (alkaline) solution. Acidic solutions have low pH due to higher H+ concentration, while neutral solutions have pH around 7. “Ionic” describes the presence of charged particles and does not specifically indicate pH level.
Category reason: This question tests the acid–base concept of pH and the definitions of acidic, neutral, and basic solutions, which are foundational chemical principles within biochemistry.

Question 29

What process produces proteins?

Accepted Answer

Answer reason: Protein production occurs during translation, when ribosomes read mRNA codons and tRNAs deliver the corresponding amino acids to build a polypeptide chain. Transcription makes RNA from a DNA template and does not directly create protein. Replication copies DNA prior to cell division, and mutation is a change in genetic sequence that may alter protein structure but is not the normal protein-synthesis step.
Category reason: The question tests the central dogma steps of gene expression and which step directly synthesizes proteins, which is a core concept in biochemistry/molecular biology rather than nursing care decisions.

Question 30

Photosynthesis primarily produces molecules of what?

Accepted Answer

Answer reason: The overall purpose of photosynthesis is to convert light energy into chemical energy stored in carbohydrates, with glucose (or its immediate precursors that form glucose) as the main product. ATP and NADPH are generated in the light reactions but are primarily short-lived intermediates used to drive carbon fixation in the Calvin cycle rather than being the primary end product. Oxygen is released as a byproduct from water splitting, not the main synthesized energy-storage molecule. Therefore, glucose best represents what photosynthesis primarily produces.
Category reason: This question tests the fundamental biochemical outcome of photosynthesis (energy conversion into carbohydrates), which is a core topic in biochemistry rather than patient-care decision-making.

Question 31

In the link reaction, pyruvate is converted into _____.?

Accepted Answer

Answer reason: The link reaction (pyruvate oxidation) converts pyruvate into acetyl-CoA via the pyruvate dehydrogenase complex in the mitochondrial matrix. During this process, one carbon is released as CO2 and NAD+ is reduced to NADH. Acetyl-CoA then enters the citric acid (Krebs) cycle to continue aerobic energy production. Oxaloacetate is regenerated within the Krebs cycle, while lactic acid and ethanol are anaerobic fermentation end products, not link reaction products.
Category reason: This question tests a core metabolic pathway step in cellular respiration (pyruvate oxidation to acetyl-CoA), which is foundational biochemical knowledge rather than a nursing care decision.

Question 32

2Na + Cl2 → 2NaCl. How many grams of NaCl from 4.6 g of Na?

Accepted Answer

Answer reason: From the balanced equation, 2 mol Na produce 2 mol NaCl, so the mole ratio Na:NaCl is 1:1. Moles of Na = 4.6 g ÷ 23 g/mol = 0.20 mol, so moles of NaCl formed = 0.20 mol. Mass of NaCl = 0.20 mol × 58.5 g/mol = 11.7 g, which corresponds to option B; however selecting based on listed answer key expectation in the image set is not possible since no key is shown.
Category reason: This is a stoichiometry/mole-to-mass conversion problem using a balanced chemical equation, which is foundational chemistry content rather than nursing care decision-making, fitting best under Biochemistry.

Question 33

What is the chemical name of common salt?

Accepted Answer

Answer reason:  Sodium chloride Common table salt is chemically sodium chloride (NaCl), an ionic compound formed from sodium (Na+) and chloride (Cl−) ions. Sodium carbonate (Na2CO3) is washing soda, calcium chloride (CaCl2) is used as a desiccant/de-icer, and potassium nitrate (KNO3) is saltpeter. Therefore the correct chemical name of common salt is sodium chloride.
Category reason: This item tests identification of a common ionic compound by its chemical name/formula, which is a core chemistry/biochemistry concept rather than nursing care decision-making.

Question 34

Which of these is a polysaccharide?

Accepted Answer

Answer reason:  Glycogen Glycogen is a polysaccharide made of many glucose units linked together and serves as the primary storage form of glucose in animals (especially liver and muscle). Glucose itself is a monosaccharide (single sugar unit). Insulin is a peptide hormone (protein), and cholesterol is a lipid (sterol), not a carbohydrate polymer.
Category reason: This question tests classification of biomolecules (mono- vs polysaccharides and other macromolecules), which is a core topic in Biochemistry.

Question 35

Cholesterol is synthesized mainly in which part of the body.?

Accepted Answer

Answer reason:  Liver The liver is the primary site of endogenous cholesterol synthesis, largely via the HMG-CoA reductase pathway in hepatocytes. It also plays a central role in packaging cholesterol into lipoproteins (e.g., VLDL) and converting cholesterol into bile acids for excretion. While many tissues can synthesize some cholesterol, hepatic production is the dominant source for whole-body cholesterol homeostasis.
Category reason: This question tests where cholesterol is synthesized in the body, a foundational biochemical concept about lipid metabolism rather than a nursing care decision, so it fits Biochemistry.

Question 36

Why does [Cu(H2O)6]+ solution appear blue in color?

Accepted Answer

Answer reason:  Due to d–d electronic transitions in the d-orbitals In the hexaaquacopper complex, ligand field splitting separates the copper d-orbitals into different energy levels. Visible light is absorbed to promote electrons between these split d levels (d–d transitions). The complementary color of the absorbed light is transmitted/observed, giving the solution its characteristic blue appearance. The color is not because copper metal or water is intrinsically blue, nor specifically due to oxygen atoms absorbing red light.
Category reason: This question tests the chemical basis of solution color due to electronic transitions in a coordination complex, which is a foundational chemistry/biochemistry concept rather than nursing care or clinical decision-making.

Question 37

Q: The maximum amount of product formed is called?

Accepted Answer

Answer reason:  Theoretical yield Theoretical yield is the calculated maximum amount of product that can be formed from given reactants assuming the reaction goes to completion with no losses. Actual yield is what is obtained experimentally and is typically lower due to side reactions and procedural losses. “Limiting yield” is not a standard term; instead, the limiting reagent determines the theoretical yield. “Excess product” is incorrect terminology because “excess” refers to a reactant, not the product.
Category reason: This question tests a foundational chemistry/stoichiometry concept (maximum possible product from a reaction), which is part of biochemical/basic chemical principles used in health sciences rather than clinical nursing decision-making.

Question 38

Which macromolecule is composed of amino acids?

Accepted Answer

Answer reason:  A) Protein Proteins are polymers made from amino acid monomers linked by peptide bonds to form polypeptide chains. Lipids are primarily built from fatty acids and glycerol, carbohydrates from monosaccharides, and nucleic acids from nucleotides. Therefore, the macromolecule composed of amino acids is protein.
Category reason: This is a foundational question about the chemical building blocks (monomers) of biological macromolecules, which is core biochemistry content rather than nursing care decision-making.

Question 39

The energy currency of a cell is?

Accepted Answer

Answer reason: ATP ATP is the primary immediate energy carrier used by cells to power processes such as active transport, muscle contraction, and biosynthesis. Hydrolysis of ATP to ADP (and inorganic phosphate) releases usable free energy via phosphate bond energy transfer. NADH is mainly an electron carrier used to generate ATP in oxidative phosphorylation, while DNA and RNA store/transfer genetic information rather than serving as the cell’s energy currency.
Category reason: This question tests foundational cellular energy metabolism and high-energy phosphate compounds, which are core topics in Biochemistry rather than nursing care decision-making.

Question 40

What is the central dogma of molecular biology?

Accepted Answer

Answer reason: DNA → RNA → Protein The central dogma describes the usual flow of genetic information: DNA is transcribed into RNA, and RNA is translated into protein. This explains how nucleotide sequence information ultimately determines amino acid sequence and protein function. While exceptions exist (e.g., reverse transcription in retroviruses), the core principle remains DNA → RNA → protein in most cells.
Category reason: This question tests the foundational flow of genetic information (transcription and translation), a core concept of molecular biology/biochemistry rather than patient-care decision-making.

Question 41

Which is a storage polysaccharide in animals?

Accepted Answer

Answer reason: Glycogen Glycogen is the primary storage polysaccharide in animals, stored mainly in the liver and skeletal muscle as a readily mobilizable glucose reserve. Cellulose is a structural polysaccharide in plant cell walls, not an animal storage form. Chitin is structural (e.g., arthropod exoskeletons and fungal cell walls). Starch is the main storage polysaccharide in plants.
Category reason: This question tests biochemical knowledge of carbohydrate storage forms (glycogen vs starch/cellulose/chitin), which is foundational biochemistry rather than nursing decision-making.

Question 42

Cabon atoms is ___?

Accepted Answer

Answer reason: C_ tetravalent Carbon has four electrons in its outer (valence) shell and typically forms four covalent bonds to complete an octet. This tetravalency explains carbon’s ability to form stable single, double, and triple bonds and to build diverse organic molecules. The other options describe atoms that commonly form 1, 2, or 3 bonds, which does not match carbon’s usual bonding behavior.
Category reason: This question tests a foundational chemical property (valency) of carbon relevant to organic chemistry and biomolecules, which falls under Biochemistry rather than nursing care decision-making.

Question 43

Which of the following bases is found only in RNA?

Accepted Answer

Answer reason: Uracil Uracil is the pyrimidine base used in RNA in place of thymine. DNA contains thymine, whereas RNA contains uracil, while adenine, cytosine, and guanine are found in both DNA and RNA. Therefore, uracil is the base found only in RNA among the listed choices.
Category reason: This question tests core nucleic acid composition (DNA vs RNA bases), which is a foundational molecular concept covered in Biochemistry rather than nursing care decision-making.

Question 44

Which is true for excess reagent?

Accepted Answer

Answer reason: Some remains unused An excess reagent is present in an amount greater than required by the balanced chemical equation relative to the limiting reagent. Because the limiting reagent is consumed first, the excess reagent is not completely consumed when the reaction stops. Therefore, some of the excess reagent remains unreacted after completion. The limiting reagent (not the excess reagent) determines the maximum amount of product formed.
Category reason: This question tests a foundational concept of reaction stoichiometry (limiting vs excess reagent) in chemistry, which fits best under Biochemistry as a basic science underpinning health sciences.

Question 45

Where in the cell does glycolysis occur?

Accepted Answer

Answer reason: Cytoplasm Glycolysis is a cytosolic metabolic pathway that converts glucose to pyruvate through a series of enzyme-catalyzed reactions in the cell’s cytoplasm. It does not require mitochondria or oxygen, so it occurs outside the mitochondria in essentially all cells. In contrast, the citric acid (Krebs) cycle and oxidative phosphorylation primarily occur within mitochondria in eukaryotic cells.
Category reason: This question tests the cellular location of a core metabolic pathway (glycolysis), which is foundational metabolism content within Biochemistry rather than a nursing care/judgment scenario.

Question 46

In a reaction, if 2 mol of X requires 1 mol of Y and you have 5 mol of X and 3 mol of Y, what is limiting?

Accepted Answer

Answer reason: X The stoichiometric ratio is 2 mol X : 1 mol Y, so 5 mol X would require 2.5 mol Y. Since 3 mol Y are available, Y is in excess relative to X. Alternatively, 3 mol Y would require 6 mol X, but only 5 mol X are present, so X limits the reaction yield.
Category reason: This question tests stoichiometry and limiting reactants, which are foundational chemical principles relevant to biochemistry rather than nursing care decision-making.

Question 47

Which atom is most abundant in the human body?

Accepted Answer

Answer reason: b) Oxygen Oxygen is the most abundant element in the human body by mass (about 65%), largely because water makes up a major fraction of body weight and oxygen is also a key component of many organic molecules. Hydrogen is the most abundant by number of atoms, but not by mass. Carbon and nitrogen are essential for biomolecules but contribute less to total body mass than oxygen.
Category reason: This is a foundational question about elemental composition of the human body, which is a core concept in biochemistry rather than nursing care decision-making.

Question 48

What type of compounds are vitamins?

Accepted Answer

Answer reason: Organic Vitamins are organic compounds required in small amounts for normal metabolism and physiologic functions, and most cannot be synthesized in sufficient quantities by the human body. They differ from minerals, which are inorganic nutrients. While some vitamins (e.g., vitamin D) are steroid-derived in structure, the class “vitamins” as a whole is defined as organic compounds, not steroids.
Category reason: This question tests the chemical nature/classification of vitamins (organic vs inorganic), which is a foundational biomolecules concept best categorized under Biochemistry rather than nursing care decisions.

Question 49

Ketosis occurs due to excess:

Accepted Answer

Answer reason: Fats Ketosis results from increased production of ketone bodies when fatty acids are used as the primary fuel source, typically due to low carbohydrate availability or insulin deficiency. Enhanced fat breakdown (lipolysis) increases hepatic ketogenesis (acetoacetate, beta-hydroxybutyrate, acetone). Proteins, vitamins, and water do not directly cause ketone body overproduction in the way excess fat metabolism does under carbohydrate deprivation.
Category reason: This question tests the metabolic basis of ketone body formation and macronutrient utilization, which is a core concept in biochemistry rather than a nursing care decision.

Question 50

Proteins are made up of?

Accepted Answer

Answer reason: Amino acids Proteins are polymers built from amino acid monomers linked together by peptide bonds. The sequence of amino acids determines the protein’s primary structure and ultimately its function after folding. Sugars form carbohydrates, fatty acids are key components of lipids, and nucleotides are the building blocks of nucleic acids (DNA/RNA).
Category reason: This is a foundational question about the chemical building blocks of macromolecules, which is core biochemistry knowledge rather than a nursing care decision.

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