Enzymes Flashcards
What are enzymes?
Enzymes are biological catalysts that speed up chemical reactions in the body.
True or False: Enzymes are consumed in the reactions they catalyze.
False
Fill in the blank: Enzymes are primarily made up of ______.
proteins
What is the role of enzymes in digestion?
Enzymes break down food into smaller molecules that can be absorbed by the body.
What is the active site of an enzyme?
The active site is the specific region on the enzyme where the substrate binds.
Multiple choice: Which of the following is an example of an enzyme? A) Amylase B) Glucose C) Lipid D) RNA
A) Amylase
What factors can affect enzyme activity?
Temperature, pH, and substrate concentration can all affect enzyme activity.
True or False: Enzymes can work on any substrate.
False
Fill in the blank: The substance that an enzyme acts upon is called a ______.
substrate
What is enzyme specificity?
Enzyme specificity refers to the ability of an enzyme to choose exact substrates from a group of similar chemical molecules.
Multiple choice: Which enzyme breaks down proteins? A) Lipase B) Protease C) Amylase D) Lactase
B) Protease
What is the significance of enzyme inhibitors?
Enzyme inhibitors are substances that decrease enzyme activity, which can be important for regulating metabolic pathways.
Fill in the blank: Enzymes that catalyze the addition of phosphate groups are known as ______.
kinases
What is the importance of coenzymes?
Coenzymes are non-protein molecules that assist enzymes in catalyzing reactions.
True or False: All enzymes require coenzymes to function.
False
Multiple choice: Which of the following is a coenzyme? A) NAD+ B) Glucose C) Protein D) Water
A) NAD+
What is enzyme denaturation?
Enzyme denaturation is the process in which an enzyme loses its structural integrity and functionality due to external factors like heat or pH changes.
Fill in the blank: The model that describes how enzymes and substrates interact is called the ______ model.
lock and key
What is the difference between competitive and non-competitive inhibition?
Competitive inhibition occurs when an inhibitor competes with the substrate for the active site, while non-competitive inhibition occurs when an inhibitor binds to a different site on the enzyme.
Multiple choice: Which enzyme is responsible for digesting carbohydrates? A) Lactase B) Protease C) Lipase D) Amylase
D) Amylase
What role do enzymes play in metabolic pathways?
Enzymes facilitate and regulate the series of biochemical reactions in metabolic pathways.
True or False: Enzymes can be reused multiple times in reactions.
True
Fill in the blank: Enzymes that catalyze the breakdown of lipids are called ______.
lipases
What is the effect of temperature on enzyme activity?
Increased temperature generally increases enzyme activity up to a certain point, after which the enzyme may denature.
Multiple choice: What is the optimal pH for most human enzymes? A) 1 B) 7 C) 8 D) 14
B) 7
What are zymogens?
Zymogens are inactive enzyme precursors that require a biochemical change to become active.
Fill in the blank: The enzyme that catalyzes the conversion of hydrogen peroxide to water and oxygen is called ______.
catalase
What is the primary function of digestive enzymes?
The primary function of digestive enzymes is to break down macromolecules into absorbable units.
True or False: Enzymes can only catalyze one type of reaction.
True
Multiple choice: Which enzyme is involved in the DNA replication process? A) RNA polymerase B) DNA ligase C) Helicase D) All of the above
D) All of the above
What is the role of allosteric sites in enzymes?
Allosteric sites are sites on an enzyme where molecules can bind, causing a change in the enzyme’s activity.
Fill in the blank: Enzymes are sensitive to changes in ______ and ______.
temperature; pH
What is the relationship between enzymes and activation energy?
Enzymes lower the activation energy required for a reaction to occur.
Multiple choice: Which of the following factors does NOT affect enzyme activity? A) Temperature B) pH C) Color D) Substrate concentration
C) Color
What are the two main types of enzymatic reactions?
The two main types are catabolic reactions (breaking down molecules) and anabolic reactions (building up molecules).
What is the primary function of lactate dehydrogenase (LDH)?
To catalyze the conversion of lactate to pyruvate, and vice versa.
True or False: Lactate dehydrogenase is an enzyme involved in anaerobic metabolism.
True
Fill in the blank: Lactate dehydrogenase plays a crucial role in the _____ cycle.
CorI cycle
What are the two main substrates for lactate dehydrogenase?
Lactate and pyruvate
Multiple Choice: Which of the following is a product of the lactate dehydrogenase reaction? A) ATP B) NADH C) NAD+ D) Pyruvate
D) Pyruvate
What is the significance of measuring lactate dehydrogenase levels in the blood?
It can indicate tissue damage or disease, such as myocardial infarction or liver disease.
True or False: Lactate dehydrogenase exists in multiple isoenzymes.
True
What cofactor is necessary for the lactate dehydrogenase reaction?
NAD+
Short Answer: Name one clinical condition associated with elevated lactate dehydrogenase levels.
Myocardial infarction
Multiple Choice: Which tissue has the highest concentration of lactate dehydrogenase? A) Brain B) Heart C) Liver D) Muscle
B) Heart
What is creatine kinase?
Creatine kinase is an enzyme that catalyzes the conversion of creatine and ATP to creatine phosphate and ADP.
True or False: Creatine kinase is primarily found in muscle tissue.
True
What are the three main isoforms of creatine kinase?
CK-MM, CK-MB, and CK-BB.
Fill in the blank: Elevated levels of creatine kinase in the blood can indicate _______.
muscle damage or injury.
Which isoform of creatine kinase is typically associated with the heart?
CK-MB
Multiple Choice: What is the primary function of creatine kinase in muscle cells? A) Energy storage B) Protein synthesis C) ATP regeneration D) Oxygen transport
C) ATP regeneration
What role does creatine phosphate play in muscle metabolism?
Creatine phosphate serves as a rapid source of energy by donating a phosphate group to ADP to regenerate ATP.
True or False: Creatine kinase levels are consistent and do not vary with physical activity.
False
What is the significance of measuring creatine kinase levels in clinical settings?
Measuring creatine kinase levels helps diagnose and monitor conditions related to muscle damage, such as myocardial infarction or rhabdomyolysis.
Short Answer: How does creatine kinase contribute to muscle recovery after exercise?
Creatine kinase helps regenerate ATP, which is crucial for muscle recovery and energy replenishment after exercise.
What does AST stand for in medical terms?
Aspartate Aminotransferase
What is another name for AST?
SGOT (Serum Glutamic-Oxaloacetic Transaminase)
True or False: AST is primarily found in the liver.
False
Which organs have the highest concentrations of AST?
Liver, heart, muscle, and kidneys
Fill in the blank: Elevated AST levels can indicate __________ damage.
tissue
What is the normal range of AST levels in the blood?
Typically 10 to 40 units per liter
Multiple Choice: Which condition is NOT commonly associated with elevated AST levels? A) Hepatitis B) Myocardial infarction C) Diabetes
C) Diabetes
What is the primary function of the AST enzyme?
To facilitate the transfer of amino groups between amino acids and keto acids.
True or False: A low AST level is always a sign of good health.
False
What additional test is often performed alongside AST to assess liver function?
ALT (Alanine Aminotransferase)
Fill in the blank: AST levels may rise due to __________ injury.
cellular
What kind of test is used to measure AST levels?
Blood test
Multiple Choice: Which factor can affect AST levels? A) Age B) Gender C) Both A and B
C) Both A and B
What does a significantly high AST level indicate?
Potential acute liver injury or myocardial infarction
True or False: AST levels can be elevated in muscle disorders.
True
What does ALT stand for?
Alanine Aminotransferase
Is ALT also known as SGPT?
True
What is the primary function of ALT in the body?
To facilitate the conversion of alanine and alpha-ketoglutarate to pyruvate and glutamate.
Which organ is primarily associated with ALT production?
The liver
What is a normal range for ALT levels in adults (in U/L)?
Typically between 7 to 56 U/L
Fill in the blank: Elevated ALT levels may indicate _____ damage.
liver
True or False: ALT levels can be affected by muscle injuries.
False
What type of test measures ALT levels?
Liver function test
Which condition is commonly associated with elevated ALT levels?
Hepatitis
Multiple Choice: Which of the following is NOT a cause of elevated ALT levels?
A) Alcohol use
B) Diabetes
C) High protein diet
D) Viral infection
C) High protein diet
What is the relationship between ALT and AST?
Both are liver enzymes, but ALT is more specific to liver injury than AST.
Fill in the blank: A significant increase in ALT levels may suggest _____ disease.
liver
True or False: ALT levels are used to diagnose liver cirrhosis.
False
What lifestyle change can help lower elevated ALT levels?
Weight loss and regular exercise
What is the significance of monitoring ALT levels in patients with chronic liver disease?
To assess liver function and monitor disease progression.
What is alkaline phosphatase?
Alkaline phosphatase is an enzyme that catalyzes the removal of phosphate groups from various molecules, including nucleotides and proteins.
True or False: Alkaline phosphatase levels can indicate liver and bone disorders.
True
Fill in the blank: The optimal pH range for alkaline phosphatase activity is typically between ___ and ___.
8.5 and 10.5
Which organ is primarily responsible for the production of alkaline phosphatase?
Liver
Multiple Choice: Which of the following conditions can lead to elevated alkaline phosphatase levels? A) Bone disease B) Liver disease C) Pregnancy D) All of the above
D) All of the above
What is the role of alkaline phosphatase in the body?
It plays a crucial role in dephosphorylation processes, aiding in digestion and bone mineralization.
True or False: Alkaline phosphatase is only found in the liver.
False
What are the main types of alkaline phosphatase isoenzymes?
Liver, bone, intestinal, and placental alkaline phosphatase.
Short Answer: How can alkaline phosphatase levels be measured?
Through a blood test.
What might elevated alkaline phosphatase levels indicate when associated with other symptoms?
Possible liver disease, bone disorders, or bile duct obstruction.
What is the primary function of acid phosphatase?
The primary function of acid phosphatase is to catalyze the hydrolysis of phosphate esters in an acidic environment.
True or False: Acid phosphatase activity is significantly higher in prostatic tissue compared to other tissues.
True
Fill in the blank: Acid phosphatase is often used as a biomarker for ________ cancer.
prostate
Which of the following is a common source of acid phosphatase in the human body? (A) Liver (B) Brain (C) Prostate (D) Skin
C) Prostate
What is the significance of measuring acid phosphatase levels in clinical diagnostics?
Measuring acid phosphatase levels can help in diagnosing prostate cancer and monitoring its progression.
What does GGT stand for?
Gamma-glutamyl transferase
True or False: GGT is primarily found in the liver.
True
What is the primary function of the GGT enzyme?
To transfer amino acids and peptides across cell membranes.
Fill in the blank: Elevated levels of GGT in the blood can indicate __________.
Liver disease or bile duct obstruction
Which organ is primarily associated with high levels of GGT?
Liver
Multiple Choice: Which of the following conditions is NOT typically associated with elevated GGT levels? A) Alcohol abuse B) Diabetes C) Hepatitis D) Cholestasis
B) Diabetes
What is a common test that measures GGT levels?
Liver function test
True or False: GGT levels can be affected by medications and alcohol consumption.
True
What can low GGT levels indicate?
Generally, low GGT levels are not associated with any significant health issues.
Fill in the blank: GGT is involved in the metabolism of __________.
Glutathione
Multiple Choice: An increase in GGT levels can be a sign of which of the following? A) Heart disease B) Kidney failure C) Liver dysfunction D) Lung cancer
C) Liver dysfunction
What other enzyme is often measured alongside GGT to assess liver health?
Alanine aminotransferase (ALT)
True or False: GGT levels are the same in all age groups.
False
Which demographic factors can influence GGT levels?
Age, sex, and ethnicity
What lifestyle factor is known to significantly elevate GGT levels?
Excessive alcohol consumption
What is amylase?
Amylase is an enzyme that catalyzes the hydrolysis of starch into sugars.
True or False: Amylase is found only in saliva.
False: Amylase is found in saliva, pancreatic juice, and other tissues.
Fill in the blank: Amylase breaks down ______ into maltose and dextrin.
starch
What are the two main types of amylase?
Salivary amylase (also known as ptyalin) and pancreatic amylase.
Multiple Choice: Which type of amylase is secreted by the pancreas?
Pancreatic amylase
What is the optimal pH for salivary amylase activity?
Approximately 6.7 to 7.0.
True or False: Amylase activity decreases in acidic conditions.
True
Short Answer: Why is amylase important in digestion?
It initiates the breakdown of carbohydrates, facilitating nutrient absorption.
What can result from a deficiency of amylase?
Malabsorption of carbohydrates and digestive issues.
Multiple Choice: Which food contains high levels of amylase?
Sprouted grains
What is lipase?
Lipase is an enzyme that catalyzes the hydrolysis of fats and lipids.
True or False: Lipase is produced primarily in the pancreas.
True
Fill in the blank: Lipase breaks down triglycerides into ______ and fatty acids.
glycerol
Which type of lipase is secreted by the pancreas?
Pancreatic lipase
What is the primary function of gastric lipase?
To initiate the digestion of dietary fats in the stomach.
Multiple Choice: What is the optimal pH range for pancreatic lipase activity? A) 1-2 B) 7-8 C) 9-10 D) 3-4
B) 7-8
What role does bile play in lipase activity?
Bile emulsifies fats, increasing the surface area for lipase to act.
True or False: Lipase only functions in the digestive system.
False
What are the products of lipase action on triglycerides?
Glycerol and free fatty acids.
What condition may result from lipase deficiency?
Malabsorption of fats, leading to conditions like steatorrhea.
What is the primary function of aldolase in the body?
Aldolase primarily catalyzes the reversible condensation of dihydroxyacetone phosphate and glyceraldehyde-3-phosphate to form fructose-1,6-bisphosphate in glycolysis.
True or False: Aldolase is an enzyme involved in the citric acid cycle.
False
Fill in the blank: Aldolase is classified as a __________ enzyme.
lyase
Which of the following is a type of aldolase? A) Aldolase A B) Aldolase B C) Aldolase C D) All of the above
D) All of the above
In which metabolic pathway does aldolase play a crucial role?
Glycolysis
