Mix Examples- Biomolecules Questions in English

(B) $ATP$ (Adenosine Triphosphate) is known as the energy currency of the cell.
It provides the immediate and ready source of energy for various cellular activities,including muscle contraction,active transport,and biosynthesis.
While glucose and glycogen are energy storage molecules,they must be broken down through cellular respiration to produce $ATP$ before their energy can be utilized by the cell.

(A) The correct sequence is $Amino \ acids \rightarrow Protein \rightarrow Enzyme$.
Amino acids are the fundamental building blocks (monomers) of proteins.
Proteins are polymers formed by the polymerization of amino acids.
Enzymes are specialized proteins (often with a prosthetic group) that catalyze biochemical reactions within the cell.
Therefore, the synthesis pathway follows the order of monomers forming polymers, which then function as enzymes.

(A) Water is often referred to as the $Universal$ $Solvent$ because of its polar nature.
When a substance is added to water,the partial electrical charges of the polar water molecules are attracted to the charged ions or partially charged polar molecules of the solute.
This attraction allows water molecules to surround and separate the solute particles,effectively dissolving a wide variety of substances.

(A) The correct answer is $A$. Water does not provide energy for chemical reactions. Energy for cellular processes is provided by $ATP$ $(Adenosine Triphosphate)$. Water acts as a universal solvent, provides a medium for metabolic reactions, and participates in ionization processes within the cell.

(B) The correct answer is $K^+$.
Potassium $(K^+)$ is the most abundant intracellular cation in living cells.
It plays a crucial role in maintaining the electrical neutrality of the cell,regulating osmotic pressure,and stabilizing cytoplasmic emulsions.
It is also essential for protein synthesis and the activation of various enzymes.

(D) The $pH$ of body fluids is maintained within a narrow range to ensure proper physiological function.
Buffer systems in the body,such as the phosphate buffer system,play a crucial role in this regulation.
Specifically,the combination of sodium and potassium phosphates acts as an effective buffer in intracellular and extracellular fluids to neutralize excess acids or bases,thereby maintaining a constant $pH$.

(D) Anabolic processes are metabolic pathways that construct molecules from smaller units,requiring energy.
$(a)$ Synthesis of carbohydrate (e.g.,photosynthesis) is an anabolic process.
$(b)$ Synthesis of fat (lipogenesis) is an anabolic process.
$(c)$ Synthesis of protein (translation) is an anabolic process.
Therefore,all the listed processes are anabolic.

(B) $ATP$ (Adenosine Triphosphate) is known as the energy currency of the cell.
It is an energy-rich compound where energy is stored in the terminal pyrophosphate bonds.
When these bonds are broken through hydrolysis,energy is released to perform various cellular activities,making it the immediate source of energy.

(C) $ATP$ stands for Adenosine Triphosphate. It acts as the primary energy currency of the cell. The energy in $ATP$ is stored in the phosphoanhydride bonds between the phosphate groups. These are specifically known as high-energy phosphate bonds. When these bonds are broken through hydrolysis,a significant amount of energy is released,which is used to drive various endergonic cellular processes.

(B) $ATP$ (Adenosine Triphosphate) is known as the energy currency of the cell.
It acts as the immediate source of energy for various cellular activities,including muscle contraction,nerve impulse conduction,and chemical synthesis.
When the terminal phosphate bond of $ATP$ is broken through hydrolysis,a significant amount of energy is released,which the cell utilizes to perform biological work.

(A) $ATP$ (Adenosine Triphosphate) is known as the energy currency of the cell. It contains high-energy phosphate bonds. When the terminal phosphate bond is hydrolyzed,a significant amount of free energy is released,which is used to drive various cellular processes. In contrast,$ADP$ has less energy than $ATP$ because it has one fewer phosphate bond. $CO_2$ and $H_2O$ are low-energy end products of cellular respiration and do not serve as energy carriers in the same capacity as $ATP$.

(A) The hydrolysis of one molecule of $ATP$ (Adenosine Triphosphate) into $ADP$ (Adenosine Diphosphate) and inorganic phosphate $(Pi)$ releases approximately $7.3 \ kcal$ of energy per mole under standard conditions.
$ATP + H_2O \rightarrow ADP + Pi + 7.3 \ kcal$.

(B) When fruits and vegetables are cut,the phenolic compounds (such as tannic acid) present in the plant cells are exposed to oxygen in the air.
In the presence of iron ions (often transferred from the metal knife) and the enzyme polyphenol oxidase,these compounds undergo oxidation.
This oxidation process leads to the formation of dark-colored pigments known as melanins,which cause the cut surface to turn brown or dark.

(B) $ATP$ (Adenosine triphosphate) acts as the primary energy currency of the cell.
When $ATP$ is converted into $ADP$ (Adenosine diphosphate),the terminal phosphate bond is broken through hydrolysis.
This reaction releases a significant amount of energy,which is utilized by the cell to perform various biological processes.

(D) $ATP$ (Adenosine Triphosphate) was discovered by Karl Lohmann in $1926$.
Later,the $ATP$ cycle was described by Fritz Lipmann in $1941$,for which he was awarded the Nobel Prize in $1953$.

(A) The hydrolysis of a single $ATP$ molecule into $ADP$ and inorganic phosphate $(Pi)$ releases approximately $7.3 \ kcal/mol$ of energy under standard conditions.
Among the given options,$8 \ kcal$ is the closest value to the standard biological estimate.

(A) $ATP$ stands for Adenosine triphosphate. It is a complex organic chemical that provides energy to drive many processes in living cells, such as muscle contraction, nerve impulse propagation, and chemical synthesis. It is often referred to as the energy currency of the cell.

(D) $ATP$ (Adenosine Triphosphate) is an energy-rich molecule.
Energy is primarily stored in the high-energy terminal phosphate bonds,specifically the phosphoanhydride bonds,which are often referred to as pyrophosphate bonds.
When these bonds are hydrolyzed,a significant amount of free energy is released to perform cellular work.

(B) The Pentose Phosphate Pathway $(PPP)$ provides Erythrose-$4$-phosphate,which is a key intermediate required for the synthesis of shikimic acid.
Shikimic acid serves as a vital precursor for the biosynthesis of aromatic amino acids and various aromatic ring compounds in plants.

(C) The pentose phosphate pathway $(PPP)$,also known as the hexose monophosphate shunt,is an alternative metabolic pathway to glycolysis.
Its primary significance includes:
$1$. The production of $NADPH$,which is essential for reductive biosynthesis (e.g.,fatty acid synthesis).
$2$. The generation of ribose-$5$-phosphate,which is a precursor for nucleotide synthesis.
$3$. The production of various sugar intermediates with $3, 4, 5, 6,$ and $7$ carbon atoms,which are utilized in various biosynthetic pathways.
$4$. Some of these intermediates,such as erythrose-$4$-phosphate and sedoheptulose-$7$-phosphate,are crucial in the Calvin cycle for $CO_2$ fixation.
Therefore,both options $(a)$ and $(b)$ are correct.

(B) The correct answer is $B$. In the human body,glucose is converted into glycogen (glycogenesis) and stored primarily in the liver and skeletal muscles. The total amount of stored glycogen is approximately $400 \text{ g}$,with about $100 \text{ g}$ stored in the liver and $300 \text{ g}$ stored in the muscles.

(A) The process of synthesizing glycogen from glucose is called $Glycogenesis$.
In the liver,excess glucose is converted into glycogen for storage,which helps in maintaining blood glucose levels.
$Glycolysis$ is the breakdown of glucose into pyruvate.
$Glycogenolysis$ is the breakdown of glycogen into glucose.
Therefore,the correct term for the synthesis of glycogen is $Glycogenesis$.

(C) Enzymes,vitamins,and hormones are all essential biological chemicals that act as regulators of various physiological processes within an organism.
Enzymes act as biological catalysts to speed up biochemical reactions.
Hormones act as chemical messengers that coordinate body activities.
Vitamins act as co-factors or essential components for metabolic pathways.
Therefore,they all collectively aid in the regulating mechanism of the body's metabolic and physiological functions.

(B) Vitamins are generally classified into two major groups based on their solubility:
$1$. Fat-soluble vitamins: These include Vitamin $A, D, E$ and $K$. They are stored in the body's fat tissues.
$2$. Water-soluble vitamins: These include Vitamin $B$-complex and Vitamin $C$. They are not stored in the body in large amounts and are excreted through urine,thus requiring regular replenishment through the diet.

(C) Vitamins are classified into two categories based on their solubility: water-soluble and fat-soluble.
Water-soluble vitamins include Vitamin $B$ complex and Vitamin $C$.
Fat-soluble vitamins include Vitamin $A, D, E$ and $K$.
These vitamins are stored in the body's fatty tissues and the liver,and they require dietary fat for absorption.

(A) Vitamin $C$ is chemically known as Ascorbic acid.
It is also referred to as the anti-scorbutic factor because its deficiency leads to the disease scurvy.
Therefore,the correct option is $A$.

(C) Vitamin $D$ is chemically known as calciferol.
It is a fat-soluble vitamin that plays a crucial role in calcium and phosphorus absorption,which is essential for maintaining healthy bones and teeth.

(C) Vitamin $C$ (ascorbic acid) is highly sensitive to heat and oxidation. When food containing Vitamin $C$ is cooked or heated,the vitamin structure breaks down,leading to its destruction. Therefore,it is considered heat labile.

(A) Hyperkeratosis is a condition characterized by the thickening of the outer layer of the skin (stratum corneum).
It is a well-documented clinical sign of hypervitaminosis $A$,which occurs due to the excessive intake of Vitamin $A$ (retinol).
Excess Vitamin $A$ interferes with normal keratinocyte differentiation,leading to the accumulation of keratin and the characteristic skin thickening associated with hyperkeratosis.

(C) The term "vitamin" was coined by Casimir Funk in $1912$. He derived it from the words "vita" (life) and "amine" (as he initially believed all vitamins were amines). Therefore, option $C$ is the correct answer.

(D) Vitamins are classified into two categories based on their solubility: fat-soluble and water-soluble.
Fat-soluble vitamins include $A, D, E,$ and $K$.
Water-soluble vitamins include the $B$-complex group and Vitamin $C$.
An antioxidant is a molecule that inhibits the oxidation of other molecules,protecting cells from damage caused by free radicals.
Vitamin $C$ (ascorbic acid) is a well-known water-soluble vitamin that functions as a potent antioxidant in the human body.
Therefore,Vitamin $C$ is both water-soluble and an antioxidant.

(D) Vitamin $B_{12}$ is chemically known as $Cyanocobalamin$. It is a water-soluble vitamin that plays a crucial role in the functioning of the brain and nervous system,and in the formation of red blood cells. It is not associated with pellagra (caused by $B_3$ deficiency),yellow enzymes (flavin enzymes),or beri-beri (caused by $B_1$ deficiency).

(D) Vitamin $B_{12}$,also known as cobalamin,is a complex organometallic compound.
It contains a central cobalt ion $(Co^{3+})$ coordinated to a corrin ring system.
$A$ characteristic feature of its structure is the presence of a cyanide group $(-CN)$ attached to the cobalt atom,forming a cobalt-cyanide linkage.
Therefore,the correct option is $D$.

(A) Vitamins are classified into two categories: fat-soluble and water-soluble.
Fat-soluble vitamins $(A, D, E, K)$ are stored in the body's fatty tissues and liver,so they are not easily excreted.
Water-soluble vitamins ($B$-complex and $C$) are not stored in the body in significant amounts.
Excess amounts of water-soluble vitamins are filtered by the kidneys and excreted through urine.
Therefore,Vitamin $C$ is the vitamin that is generally excreted in human urine.

(A) The vitamin theory was proposed by Frederick Gowland Hopkins and Casimir Funk in $1912$.
Casimir Funk is credited with coining the term 'vitamine' (vital amine) after isolating a substance from rice polishings that could cure beriberi.
Hopkins contributed significantly by demonstrating that certain accessory food factors (vitamins) are essential for health and growth,even if present in minute quantities.

(B) Vitamin $D$ is essential for the absorption of calcium from the gastrointestinal tract.
Excessive intake of vitamin $D$ leads to an abnormally high level of calcium in the blood,a condition known as $Hypercalcemia$.
This excess calcium is often mobilized from the bones through bone reabsorption,which can lead to weakened bones and the deposition of calcium in soft tissues.

(D) Vitamin $D$ is known as the anti-rachitic vitamin.
It plays a crucial role in the absorption of calcium and phosphorus from the intestine,which is essential for healthy bone development.
$A$ deficiency of Vitamin $D$ leads to rickets in children and osteomalacia in adults,characterized by the softening and weakening of bones.

(C) The anti-scorbutic vitamin is $Vitamin \ C$ (ascorbic acid).
It is called anti-scorbutic because it prevents the deficiency disease known as scurvy in humans.

(B) The vitamin $B$ complex consists of several water-soluble vitamins that play important roles in cell metabolism.
$Riboflavin$ is vitamin $B_2$.
$Cyanocobalamine$ is vitamin $B_{12}$.
$Nicotinamide$ is a form of vitamin $B_3$ (Niacin).
$Nicotin$ (or nicotine) is an alkaloid found in the nightshade family of plants,particularly tobacco,and is not a vitamin or part of the vitamin $B$ group.

(A) Vitamin $A$ was discovered by $McCollum$ and $Davis$ in $1915$.
They isolated it from butter and egg yolk,identifying it as a fat-soluble growth factor.

(C) Vitamin $E$ (tocopherol) is sensitive to light and is destroyed by exposure to ultraviolet $(UV)$ rays. It is also susceptible to oxidation,which leads to the loss of its biological activity.

(C) Vitamin $M$ is an older term for Folic acid (also known as Vitamin $B_9$).
It was historically named Vitamin $M$ because it was found to be essential for the growth of monkeys (the letter $M$ stands for 'monkey').
Folic acid is crucial for $DNA$ synthesis,repair,and methylation,and it plays a vital role in the production of red blood cells.

(B) Cow's milk appears slightly yellowish in colour primarily due to the presence of $Riboflavin$ (also known as $Vitamin B_2$).
$Riboflavin$ is a water-soluble vitamin that exhibits an orange-yellow pigment,which imparts this characteristic colour to the milk.

(B) Vitamins are classified into two groups based on their solubility: fat-soluble and water-soluble.
Fat-soluble vitamins (e.g.,$A, D, E, K$) can be stored in the body's adipose tissue and liver,so they do not need to be consumed every single day.
Water-soluble vitamins (e.g.,$B$-complex and $C$) are not stored in the body in significant amounts and are excreted through urine.
Therefore,water-soluble vitamins must be replenished through our daily diet to maintain optimal health.

(D) The correct answer is $D$.
Vitamin $C$ (ascorbic acid,$C_6H_8O_6$) is known as the antiscorbutic vitamin.
It is abundantly found in fresh vegetables and citrus fruits like lemons,oranges,tomatoes,and pineapples.
Vitamin $C$ is essential for the synthesis of collagen fibers,which are vital for wound healing and maintaining connective tissues.
$A$ deficiency of Vitamin $C$ leads to a disease called scurvy,characterized by bleeding gums and delayed wound healing.
Unlike many animals that can synthesize it,humans and apes must obtain it through their diet.

(A) Vitamin $A$ is known as the antixerophthalmia vitamin because its deficiency leads to xerophthalmia,a condition characterized by dryness of the conjunctiva and cornea of the eye.
Vitamin $A$ (retinol) is essential for maintaining healthy vision and epithelial tissues.

(C) Fish-liver oils,such as cod-liver oil,are well-known natural sources of fat-soluble vitamins.
Specifically,they are rich in Vitamin $A$ (retinol) and Vitamin $D$ (calciferol).
Vitamin $A$ is essential for vision and immune function,while Vitamin $D$ is crucial for calcium absorption and bone health.

(D) Folic acid is known as Vitamin $B_9$ and pantothenic acid is known as Vitamin $B_5$.
Both of these vitamins are water-soluble and are essential components of the Vitamin $B$ complex group.
Therefore,they belong to the Vitamin $B$ complex family.

(A) The intracellular fluid $(ICF)$ contains high concentrations of potassium ions $(K^+)$ and magnesium ions $(Mg^{2+})$,with potassium being the most abundant intracellular cation.
In contrast,the extracellular fluid $(ECF)$ is rich in sodium ions $(Na^+)$ and chloride ions $(Cl^-)$.
Therefore,potassium is the dominant intracellular cation.