Multiple Choice
Which of the following is a monosaccharide?
Glucose
Glucose is a monosaccharide, the simplest form of carbohydrate.
Which carbohydrate is a disaccharide?
Sucrose
Sucrose is a disaccharide composed of glucose and fructose.
What is the primary storage form of carbohydrates in plants?
Starch
Starch is a polysaccharide used by plants to store energy.
Which carbohydrate is important for digestive health and cannot be digested by the body?
Fiber
Fiber is a type of carbohydrate that the body cannot digest, aiding in digestive health.
Where does carbohydrate digestion begin in the body?
Mouth
Carbohydrate digestion begins in the mouth with the enzyme salivary amylase.
In which organ are fructose and galactose primarily converted into glucose?
Liver
Fructose and galactose are transported to the liver where they are converted into glucose or other metabolites.
What is the process of breaking down glucose to produce energy called?
Glycolysis
Glycolysis is the process of breaking down glucose into pyruvate, generating energy.
Which metabolic pathway involves breaking down glycogen into glucose?
Glycogenolysis
Glycogenolysis involves breaking down glycogen into glucose when the body needs energy.
What is the process of creating glucose from non-carbohydrate sources?
Gluconeogenesis
Gluconeogenesis is the creation of glucose from non-carbohydrate sources, especially during low glucose availability.
Which pathway generates NADPH and ribose-5-phosphate?
Pentose Phosphate Pathway
The Pentose Phosphate Pathway produces NADPH and ribose-5-phosphate, essential for biosynthesis and antioxidant defense.
Which carbohydrate is crucial for promoting regular bowel movements?
Fiber
Fiber is a type of carbohydrate that aids in maintaining regular bowel movements and digestive health.
Which type of carbohydrate provides sustained energy and helps maintain stable blood sugar levels?
Complex carbohydrates
Complex carbohydrates are digested slowly, providing sustained energy and stable blood sugar levels.
Which of the following are examples of complex carbohydrates?
Whole grains, legumes, vegetables, fruits
Whole grains, legumes, vegetables, and fruits are examples of complex carbohydrates that provide long-lasting energy.
What is the main carbohydrate used by the brain for energy?
Glucose
Glucose is the primary energy source for the brain and is crucial for cognitive function.
What is the storage form of carbohydrates in animals?
Glycogen
Glycogen is the storage form of glucose in animals, found primarily in the liver and muscles.
Which enzyme begins carbohydrate digestion in the mouth?
Salivary amylase
Salivary amylase is the enzyme that begins the digestion of carbohydrates in the mouth.
Which enzyme is responsible for breaking down lactose in the small intestine?
Lactase
Lactase is the enzyme that breaks down lactose into glucose and galactose in the small intestine.
Which enzyme breaks down maltose into glucose?
Maltase
Maltase breaks down maltose into two glucose molecules in the small intestine.
Which carbohydrate is composed of glucose and fructose?
Sucrose
Sucrose is a disaccharide made up of glucose and fructose, commonly found in table sugar.
What is a key benefit of consuming complex carbohydrates?
Blood sugar regulation
Complex carbohydrates, especially those high in fiber, help slow down glucose absorption, leading to stable blood sugar levels.
Which of the following is a source of complex carbohydrates?
Whole grains
Whole grains are rich in fiber and nutrients, making them a healthy source of carbohydrates.
What is a characteristic of simple carbohydrates?
Rapidly digested, causing quick energy spikes
Simple carbohydrates are quickly digested, leading to fast energy release and potential blood sugar spikes.
Which of the following is an example of simple carbohydrates?
Candy, soda, fruit juice, table sugar
These foods are high in simple sugars, which are quickly absorbed by the body.
What is one benefit of consuming soluble fiber?
Lowers cholesterol levels
Soluble fiber helps reduce cholesterol, promoting heart health.
Which type of fiber helps add bulk to stool and aids in preventing constipation?
Insoluble fiber
Insoluble fiber adds bulk to stool, helping with regular bowel movements and preventing constipation.
Which type of fiber helps regulate blood sugar levels and lower cholesterol?
Soluble fiber
Soluble fiber dissolves in water and can help lower blood cholesterol and glucose levels.
Consuming complex carbohydrates can help reduce the risk of which chronic disease?
Type 2 diabetes
A diet high in whole grains and fiber-rich carbohydrates can reduce the risk of type 2 diabetes by improving insulin sensitivity.
Which metabolic pathway occurs in the mitochondria and produces ATP, NADH, and FADH2?
The citric acid cycle
The citric acid cycle occurs in the mitochondria and is a key part of cellular respiration, producing ATP, NADH, and FADH2 from carbohydrate metabolites.
Which pathway generates a large amount of ATP by using electrons from NADH and FADH2?
Electron transport chain
The electron transport chain uses electrons from NADH and FADH2 to generate a large amount of ATP, making it the final stage of aerobic respiration.
What is the process of converting glucose into glycogen for storage called?
Glycogenesis
Glycogenesis is the process of converting glucose to glycogen for storage in the liver and muscles.
Which process helps maintain blood glucose levels during fasting or low-carbohydrate diets?
Gluconeogenesis
Gluconeogenesis occurs during prolonged fasting or low-carbohydrate intake, producing glucose from non-carbohydrate sources.
What are the main products of the Pentose Phosphate Pathway?
NADPH and ribose-5-phosphate
The Pentose Phosphate Pathway produces NADPH, important for biosynthesis and antioxidant defense, and ribose-5-phosphate, crucial for nucleotide synthesis.
What is the role of NADPH and ribose-5-phosphate produced in the Pentose Phosphate Pathway?
NADPH is used in fatty acid synthesis and ribose-5-phosphate in nucleotide synthesis.
NADPH provides reducing power for fatty acid synthesis and other biosynthetic reactions, while ribose-5-phosphate is a precursor for nucleotide synthesis.
What type of carbohydrate is composed of long chains of sugar molecules?
Polysaccharides
Polysaccharides are long chains of monosaccharide units, making them complex carbohydrates.
Which two carbohydrates serve as storage forms of energy in plants and animals?
Starch and glycogen
Starch and glycogen are both storage polysaccharides; starch is used by plants, while glycogen is used by animals.
In which cellular organelle does the citric acid cycle take place?
Mitochondria
The citric acid cycle occurs in the mitochondria, which is the powerhouse of the cell.
Which of the following foods is high in simple carbohydrates?
Candy, soda, and pastries
Candy, soda, and pastries are high in simple carbohydrates, which can lead to rapid blood sugar spikes.
What is a common effect of consuming simple carbohydrates?
Rapid energy spikes followed by crashes
Simple carbohydrates cause quick increases in blood sugar, leading to rapid energy spikes and subsequent crashes.
Which polysaccharide serves as a structural component in plant cell walls?
Cellulose
Cellulose is a type of fiber found in plant cell walls and is not digestible by humans, providing structural support.
Which monosaccharide is commonly found in fruits and gives them their sweetness?
Fructose
Fructose is a monosaccharide commonly found in fruits and honey, contributing to their sweet taste.
Which part of the body relies heavily on carbohydrates for energy?
The brain and nervous system
The brain and nervous system primarily rely on glucose for energy, making carbohydrates crucial for their function.
Which foods are best for providing long-lasting energy and supporting digestive health?
Whole grains, fruits, and vegetables
Whole grains, fruits, and vegetables are rich in complex carbohydrates and fiber, promoting digestive health and stable energy levels.
What happens during glycogenolysis?
Glycogen is broken down into glucose during energy demand.
During glycogenolysis, glycogen is converted into glucose to meet the body's energy needs, especially during physical activity or fasting.
What is the role of the electron transport chain in cellular respiration?
NADH and FADH2 donate electrons to generate ATP.
In the electron transport chain, NADH and FADH2 transfer electrons, leading to the production of ATP through oxidative phosphorylation.
What is a primary benefit of dietary fiber in the digestive system?
Fiber helps prevent constipation and regulates bowel movements.
Fiber adds bulk to stool and aids in maintaining regular bowel movements, promoting digestive health.
Which macronutrient is the body's primary source of energy?
Carbohydrates
Carbohydrates are broken down into glucose, which is the primary energy source for the body, especially in high-intensity activities.
Which of the following is an example of a food high in added sugars?
Candy and sugary drinks
Candy and sugary drinks contain high amounts of added sugars, leading to quick energy spikes.
What is a typical effect of consuming simple carbohydrates like sugar?
Provides rapid energy that quickly diminishes
Simple carbohydrates provide quick energy that doesn't last, leading to a rapid drop in energy levels.