Podcast
Podcast
Podcast
Something went wrong
Questions and Answers
Questions and Answers
Which of the following is the primary role of an enzyme in a biochemical reaction?
Which of the following is the primary role of an enzyme in a biochemical reaction?
- To alter the equilibrium of the reaction, favoring product formation.
- To provide energy for the reaction to occur spontaneously.
- To act as a reactant and become part of the final product.
- To act as a catalyst, speeding up the reaction without being consumed. (correct)
The suffix '-ase' is most commonly used to denote which type of biomolecule?
The suffix '-ase' is most commonly used to denote which type of biomolecule?
- Vitamins that act as coenzymes in metabolic pathways.
- Lipids involved in energy storage and cell membrane structures.
- Enzymes catalyzing specific biochemical reactions in cells. (correct)
- Carbohydrates that serve as primary energy source.
What is the function of hydrolase enzymes?
What is the function of hydrolase enzymes?
- They catalyze oxidation reactions in cellular respiration and detoxification.
- They catalyze the formation of new bonds between molecules, often requiring ATP.
- They catalyze the transfer of functional groups between different substrates.
- They catalyze reactions involving the addition of water to break chemical bonds. (correct)
Which class of enzymes is responsible for catalyzing oxidation-reduction reactions?
Which class of enzymes is responsible for catalyzing oxidation-reduction reactions?
L-amino acid oxidase is an enzyme that catalyzes which of the following reactions?
L-amino acid oxidase is an enzyme that catalyzes which of the following reactions?
Which subclass of oxidoreductases is responsible for introducing double bonds into a substrate?
Which subclass of oxidoreductases is responsible for introducing double bonds into a substrate?
What is the primary function of transferase enzymes?
What is the primary function of transferase enzymes?
Ligases catalyze which type of reaction?
Ligases catalyze which type of reaction?
Which class of enzymes is involved in the conversion of D to L isomers, or vice versa?
Which class of enzymes is involved in the conversion of D to L isomers, or vice versa?
What effect does increasing substrate concentration typically have on enzyme activity, assuming enzyme concentration is constant?
What effect does increasing substrate concentration typically have on enzyme activity, assuming enzyme concentration is constant?
How does temperature generally affect enzyme activity?
How does temperature generally affect enzyme activity?
Why does enzymatic browning occur in fruits and vegetables when they are cut or bruised?
Why does enzymatic browning occur in fruits and vegetables when they are cut or bruised?
Which enzyme is often elevated in blood serum and used as an indicator of heart or liver damage?
Which enzyme is often elevated in blood serum and used as an indicator of heart or liver damage?
The appearance of certain enzymes not normally found in the blood can indicate:
The appearance of certain enzymes not normally found in the blood can indicate:
What is the primary reason dietary intake of water-soluble vitamins needs to be more frequent than that of fat-soluble vitamins?
What is the primary reason dietary intake of water-soluble vitamins needs to be more frequent than that of fat-soluble vitamins?
Which of the following is a key function of Vitamin C in the body?
Which of the following is a key function of Vitamin C in the body?
Which vitamin is synthesized through a biochemical pathway involving L-Gulonic acid, lactonase, and oxidase?
Which vitamin is synthesized through a biochemical pathway involving L-Gulonic acid, lactonase, and oxidase?
Which of the following is a common dietary source of Vitamin C?
Which of the following is a common dietary source of Vitamin C?
What is the primary function of Vitamin B1 (Thiamine) in the body?
What is the primary function of Vitamin B1 (Thiamine) in the body?
For which of the following processes is Vitamin A (retinol) essential?
For which of the following processes is Vitamin A (retinol) essential?
Which of the following accurately describes the role of Vitamin A in regulating cell differentiation?
Which of the following accurately describes the role of Vitamin A in regulating cell differentiation?
What is the primary way humans obtain Vitamin D?
What is the primary way humans obtain Vitamin D?
Vitamin D plays a critical role in:
Vitamin D plays a critical role in:
What is the primary function of Vitamin E in the body?
What is the primary function of Vitamin E in the body?
Which of the following is a key function of Vitamin K?
Which of the following is a key function of Vitamin K?
Which of the following can lead to a high risk of nutrient deficiencies?
Which of the following can lead to a high risk of nutrient deficiencies?
Which of the following is a common symptom of nutrient deficiency?
Which of the following is a common symptom of nutrient deficiency?
Which processes can cause the loss of nutritional value in foods?
Which processes can cause the loss of nutritional value in foods?
What is the practice of adding nutrients to foods to restore the original concentrations that may have been lost during processing?
What is the practice of adding nutrients to foods to restore the original concentrations that may have been lost during processing?
What is the key difference between the terms 'enrichment' and 'fortification' when discussing addition of nutrients to food?
What is the key difference between the terms 'enrichment' and 'fortification' when discussing addition of nutrients to food?
What is the primary purpose of a Dietary Reference Intake (DRI)?
What is the primary purpose of a Dietary Reference Intake (DRI)?
Which of the following best describes the Recommended Daily Allowance (RDA)?
Which of the following best describes the Recommended Daily Allowance (RDA)?
What does Adequate Intake (AI) refer to in the context of Dietary Reference Intakes?
What does Adequate Intake (AI) refer to in the context of Dietary Reference Intakes?
What is the significance of the Upper Tolerable Intake Level (UL) in dietary recommendations?
What is the significance of the Upper Tolerable Intake Level (UL) in dietary recommendations?
Beyond carbohydrates, proteins, and fat - what are other components found in functional foods?
Beyond carbohydrates, proteins, and fat - what are other components found in functional foods?
How do antioxidants primarily benefit the body?
How do antioxidants primarily benefit the body?
What is the source of heme iron?
What is the source of heme iron?
Which of the following is a primary function of zinc in the human body?
Which of the following is a primary function of zinc in the human body?
Which mineral contributes to bone structures, muscle contraction and heart rate?
Which mineral contributes to bone structures, muscle contraction and heart rate?
Why should fat-soluble vitamins be taken with food?
Why should fat-soluble vitamins be taken with food?
Questions and Answers
Something went wrong
Flashcards
Flashcards
Enzymes
Enzymes
Organic compounds acting as catalysts in biochemical reactions.
-ase
-ase
Suffix that identifies a substance as an enzyme. Examples: urease, sucrase, lipase.
Oxidase
Oxidase
Enzymes catalyzing oxidation reactions.
Hydrolase
Hydrolase
Signup and view all the flashcards
Oxidoreductase
Oxidoreductase
Signup and view all the flashcards
Transferase
Transferase
Signup and view all the flashcards
Hydrolase
Hydrolase
Signup and view all the flashcards
Lyase
Lyase
Signup and view all the flashcards
Isomerase
Isomerase
Signup and view all the flashcards
Ligase
Ligase
Signup and view all the flashcards
Substrate Concentration
Substrate Concentration
Signup and view all the flashcards
Enzyme Concentration
Enzyme Concentration
Signup and view all the flashcards
Temperature (Enzymes)
Temperature (Enzymes)
Signup and view all the flashcards
pH (Enzymes)
pH (Enzymes)
Signup and view all the flashcards
Discoloration of Fruits
Discoloration of Fruits
Signup and view all the flashcards
Lactate dehydrogenase (LDH)
Lactate dehydrogenase (LDH)
Signup and view all the flashcards
Creatinine phosphokinase (CPK)
Creatinine phosphokinase (CPK)
Signup and view all the flashcards
Vitamins
Vitamins
Signup and view all the flashcards
Water Soluble Vitamins
Water Soluble Vitamins
Signup and view all the flashcards
Fat Soluble Vitamins
Fat Soluble Vitamins
Signup and view all the flashcards
Vitamin C
Vitamin C
Signup and view all the flashcards
Vitamin C Functions
Vitamin C Functions
Signup and view all the flashcards
Vitamin C Sources
Vitamin C Sources
Signup and view all the flashcards
Vitamin B Family Functions
Vitamin B Family Functions
Signup and view all the flashcards
Fat-Soluble Vitamins
Fat-Soluble Vitamins
Signup and view all the flashcards
Vitamin A
Vitamin A
Signup and view all the flashcards
Vitamin D
Vitamin D
Signup and view all the flashcards
Vitamin D Sources
Vitamin D Sources
Signup and view all the flashcards
Vitamin E
Vitamin E
Signup and view all the flashcards
Vitamin K
Vitamin K
Signup and view all the flashcards
High Risk for Nutrient Deficiency
High Risk for Nutrient Deficiency
Signup and view all the flashcards
Nutrient Deficiency Symptoms
Nutrient Deficiency Symptoms
Signup and view all the flashcards
Loss of Nutritive Value
Loss of Nutritive Value
Signup and view all the flashcards
Vitamin Deficiency Diseases
Vitamin Deficiency Diseases
Signup and view all the flashcards
Addition of Nutrients to Food
Addition of Nutrients to Food
Signup and view all the flashcards
Dietary Recommendations
Dietary Recommendations
Signup and view all the flashcards
Calcium Sources
Calcium Sources
Signup and view all the flashcards
Phosphorus
Phosphorus
Signup and view all the flashcards
Good sources of magnesium.
Good sources of magnesium.
Signup and view all the flashcards
Electrolyte Sources
Electrolyte Sources
Signup and view all the flashcards
Sources of iron
Sources of iron
Signup and view all the flashcards
Flashcards
Something went wrong
Study Notes
Study Notes
Enzymes
- Enzymes are organic compounds that act as catalysts for biochemical reactions.
- Bread dough rising is a result of CO2 production from yeast acting on sugars.
Classification of Enzymes
- The suffix "-ase" identifies a substance as an enzyme, like urease, sucrase, and lipase.
- Pepsin, chymotrypsin, and trypsin are digestive enzymes.
- The type of reaction an enzyme catalyzes is often noted with a prefix such as Oxidase (catalyzes oxidation) and Hydrolase (catalyzes hydrolysis).
- The identity of the substrate is often included in the enzyme name, such as glucose oxidase, pyruvate carboxylase, and succinate dehydrogenase.
- Cellulase functions in the hydrolysis of cellulose.
- L-amino acid oxidase functions in the oxidation of L-amino acid.
- Lactate dehydrogenase functions in the removal of hydrogen from lactate ion.
Main Classes and Subclasses of Enzymes
- Oxidoreductases catalyze oxidation/reduction reactions, using subclasses like oxidases, reductases, and dehydrogenases.
- Transferases catalyze the transfer of functional groups, exemplified by transaminases and kinases.
- Ligases catalyze the formation of new bonds, including synthetases and carboxylases.
- Lyases catalyze the removal of groups to form double bonds, employing dehydratases, decarboxylases, deaminases, and hydratases.
- Isomerases catalyze the conversion between isomers, using racemases.
Enzyme Class Examples
- Oxidoreductases catalyze oxidation-reduction reactions, like lactate dehydrogenase removing hydrogen from a molecule.
- Transferases catalyze the transfer of a functional group from one molecule to another.
- Hydrolases catalyze hydrolysis reactions where water addition breaks a bond, and examples include carbohydrases, proteases and lipases.
- Lyases catalyze the addition of a group to a double bond (or removal to form double bond), like Fumarase.
- Isomerases catalyze the isomerization of a substrate (rearrangement of atoms), like Phosphoglyceromutase.
- Ligases catalyze the bonding of two molecules using ATP, exemplified by pyruvate carboxylase.
Factors Affecting Enzyme Activity
- Reaction rate increases with substrate concentration until full saturation occurs, then the rate levels off.
- Reaction rate increases with increasing enzyme concentration, assuming enzyme concentration is much lower than that of substrate.
- Temperature: Reaction rate increases with temperature until the protein is denatured and activity stops sharply.
- pH: Maximum enzymatic activity is possible only within a narrow pH range; outside this pH range, the protein is denatured.
Discoloration of Fruits & Vegetables
- Exposure of the fruit's tissues to oxygen results in discoloration, also known as the "browning reaction".
- The browning reaction is caused by the phenolase enzyme (oxidoreductase).
- Enzymatic browning can be prevented by immersing sliced fruits in cold water, refrigeration, or boiling, which destroys the enzyme.
- Adding lemon juice to sliced fruits inhibits enzymatic activity of phenolase; Vitamin C in lemon serves as an antioxidant which produces colorless oxidation products.
Medical Uses of Enzymes
- The appearance of certain enzymes not normally found in the blood can indicate tissue damage in an organ.
- Assays of abnormal enzyme activity in blood serum can be used to diagnose disease states.
- Lactate dehydrogenase (LDH), Creatinine phosphokinase (CPK), Aspartate transaminase (AST), and Alanine transaminase (ALT) are examples of enzymes which can indicate heart or liver disease.
- Heart attack symptoms include irregular breathing and pain in the left chest that may radiate to the neck, left shoulder & arm.
- Heart attack risk factors include family history, smoking, high blood pressure, diabetes, being overweight, poor diet, and stress.
Characteristics of Vitamins
- Vitamins are organic compounds essential in small amounts for proper body function.
- The word "vitamin" is derived from the Latin word "vita," meaning "life".
- Required amounts of vitamins are expressed as micrograms or milligrams.
- A well-balanced diet usually meets the body's vitamin requirements.
Water-Soluble vs. Fat-Soluble Vitamins
- Water-soluble vitamins are absorbed directly into the blood, while fat-soluble vitamins first enter the lymph system.
- Water-soluble vitamins travel without protein carriers, while fat-soluble vitamins often require protein carriers.
- Water-soluble vitamins circulate in the water-filled parts of the body, while fat-soluble vitamins are found in cells associated with fat.
- The kidneys remove excess water-soluble vitamins in urine, but fat-soluble vitamins tend to remain in fat-storage sites.
- Water-soluble vitamins are not likely to reach toxic levels unless taken in very large doses; fat-soluble vitamins are likely to reach toxic levels when consumed from supplements.
- Water-soluble vitamins need to be replenished in frequent doses, while fat-soluble vitamins are needed in periodic doses.
- Water-soluble vitamins function as coenzymes, while fat-soluble vitamins do not.
- Water-soluble vitamins include thiamine, riboflavin, niacin, vitamin B6, folate, vitamin B12, pantothenic acid, biotin, and vitamin C and must be replenished often because they are easily eliminated from the body in urine.
Water Soluble Vitamins
- Vitamin C: Ascorbic Acid is required in the diet of humans, monkeys, apes and guinea pigs.
- Vitamin C is a cyclic ester, forming a ring structure.
- Vitamin C functions as a co-substrate in the formation of structural protein collagen and in the biosynthesis of the amino acids, hydroxyproline and hydroxylysine.
- Vitamin C acts as a specific antioxidant and general antioxidant for water soluble substances in blood and other body fluids.
- Vitamin C is often added to foods as a preservative and is involved in the metabolism of several amino acids.
- Sources of Vitamin C include oranges (50 mg per 100 g), strawberries (60 mg per 100 g), bell peppers (128 g per 100 g), and cabbage (60 mg per 100g).
- Vitamin B family components of coenzymes in the human body and must be chemically modified before they can be usable as coenzymes.
- Dietary sources of B Vitamins include fruits (bananas/watermelon/oranges), vegetables (mushrooms/leafy greens/potato/squash), whole wheat products, whole grains, fortified cereals, chicken, fish, red meat, animal liver, eggs, legumes, peanuts and soybeans.
Fat Soluble Vitamins
- The fat-soluble vitamins are designated as A, D, E, K and are stored mostly in the liver.
- Vitamin A (retinol) is involved in Vision, Cell Differentiation, Health of Epithelial Tissues, and Reproduction and Growth.
- Vitamin D is produced in the skin of humans and animals by the action of sunlight (UV light); food sources include liver, fatty fish (salmon), egg yolks, foods fortified with Vit D (milk, margarine).
- Vitamin D is needed for maintenance of normal blood levels of calcium and phosphate ions.
- Vitamin E has four forms (alpha, beta, delta and gamma-tocopherol) and its primary function is an antioxidant.
- Vitamin E exerts its antioxidant effect in the lungs and is involved in the conversion of Arachidonic acid to prostaglandins.
- Sources include plants oils (products like magarine, salad dressings and shortenings), green and leafy vegetables and whole grain products.
- Vitamin K is essential to the blood clotting process and is required for the biosynthesis of several other proteins in the plasma, bone and kidney; half of the body's Vitamin K is synthesized by intestinal bacteria, the other half from diet.
- Sources include green leafy vegetables like spinach and cabbage ,peas and tomatoes and animal tissues like liver.
Nutrient Deficiencies
- High risk groups for nutrient deficiencies include those with restricted food intake, elimination of food groups, diets low in nutrients, older adults, pregnant women, and vegans.
- Increased nutrient needs can also be caused by a health condition and some medications.
- Nutrient deficiency symptoms include cracks/sores in mouth and lips, digestive disturbances, loss of appetite, weakness, insomnia, muscle cramps/weakness, nerve damage, anemia, and fatigue.
- Deficiency of certain vitamins resulted to widespread diseases in the early 20th century and included rickets (Vit D), scurvy (Vit C), beri-beri (Vit B complex) and pellagra (Vit B complex) which were thought to be infectious diseases.
- Nutritional value can be lost by light, heat, oxidation, bacteria, enzymes and harvesting/post-harvest facilities, processing or handling methods, as well as storage.
Addition of Nutrients to Food
- By 1900, biochemists and physiologists had identified protein, fat, and carbohydrates as the basic nutrients in food.
- By 1916, new data had led to the discovery that food contained vitamins, and the lack of "vital amines" could cause disease.
- The focus of nutrition programs shifted in the second half of the century from disease prevention to control chronic conditions, such as cardiovascular disease and obesity.
- Enrichment involves addition of specific amounts of selected nutrients in accordance with a standard of identity as defined by the U.S. Food and Drug Administration (FDA).
- Restoration involves addition to restore the original concentration of key nutrients.
- Nutrification is a generic term intended to encompass any addition of nutrients to food.
- Fortification involves addition of nutrients in amounts significant enough to render the food a good to superior source of the added nutrients
- Dietary Reference Intake are the best available evidence-based nutrient standards for estimating optimal intakes.
- RDA (Recommended Daily Allowance) serves as intake goals for healthy individuals, meeting or exceeding the estimated requirements of 97-98 % of the population.
- AI (Adequate Intake) is used when data is insufficient to determine an RDA and is likely to exceed the actual requirements of almost healthy adults.
- EAR (Estimated Average Requirement): The amount estimated to meet the needs of 50 % of individuals.
- UL (Upper Tolerable) Intake Level is above which toxicity is likely to occur.
- RENI (Recommended Energy and Nutrient Intake) is based on Philippine RDA (by Food and Nutrition Research Institute).
- Common myth: Natural source is more superior from synthetic, Truth : the body cannot tell the difference whether the source is synthetic (manufactured in the laboratory) and gets the same benefit.
- There are 13 known vitamins.
- A diet high in fiber and low in fats is the best way to meet the daily nutritional needs and vitamin supplements do not provide energy or calories.
- Supplements are best when accompanied by a well balanced diet and should not replace a healthy diet.
- For most part of vitamins, supplements are safe to take.
- Fat soluble vitamins are more likely to be toxic than water soluble vitamins.
Minerals
- Minerals regulate body processes and give structure to things in the body, contribute no calories, and cannot be destroyed by heat.
- Major minerals include calcium, phosphorus, magnesium, and electrolytes (sodium, chloride, potassium); trace minerals include chromium, copper, fluoride, iodine, iron, manganese, selenium, and zinc.
- Calcium - natural sources include milk, yogurt and cheese.
- Key functions of Phosphorus are to generate energy, regulate energy metabolism and is a component of DNA, RNA, bones and teeth.
- Key functions of Magnesium are to regulate body functions as part of 300 enzymes.
- Chloride, Potassium and Sodium are types of Electrolytes.
- Iron is part of hemoglobin and carries oxygen; sources include animals (heme), plants (non-heme), and vitamin C helps absorption.
- Zinc supports the health of the immune system; a deficiency is common and can be affected by smoking and excessive alcohol consumption.
- Food cravings can indicate specific nutrient needs, such as craving chocolate could indicate a need for Magnesium.
- Functional foods provide benefits beyond basic nutrition, such as phytonutrients, prebiotics/probiotics, fatty fish/omega 3's, oats, soy protein, and flaxseed.
- Antioxidants slow damage of body cells, improve immune function and are found in colourful fruits/veggies and grains; Vitamin C, Vitamin E and Carotenoids are examples.
- Phytonutrients "Spark" body processes that may fight or reduce the risk of some diseases; examples include carotenoids, lutein, lycopene, flavanols, prebiotics/probiotics, and soybeans.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Study Notes
Something went wrong
