Chapter 2: Carbohydrates
Which statements explain the functions of fiber in overall health?
-Slows down digestions to increase satiety. -Increases fecal bulk to ease bowel movements -Slows down the release of glucose into the blood -Binds bile acids in the gut to reduce circulating cholesterol
Glycogen
-form in which carbohydrates are stored in the body. -Polysaccharide -Limited amount of glycogen is stored in the skeletal muscles and the liver for energy use. -The branch structure makes it possible to yield glucose quickly. -Not consumed in the diet; body takes glucose and builds glycogen to be stored for quick released.
Which sugar is an example of a monosaccharide?
Fructose
Monosaccharides
-Single saccharide units with six carbon atoms. -they are the building blocks for all other carbohydrates -All monosaccharides are simple sugars. -Glucose -Fructose -Galactose
which foods contain carbohydrates with beta bonds?
-Apple -Granola -Bran muffin -Wheat bread
2 forms of carbohydrates found in the body
-Blood glucose -Glycogen
Which foods are good sources of dietary fiber?
-Bran cereal -Honey Oat Bread -Flaxseed crackers
Disaccharides
-Double saccharide units composed of two monosaccharides with a single bond linking them together. -All three disaccharides are simple sugars -Sucrose -Maltose -Lactose
Blood glucose
-Found in blood circulation -Monosaccharide -exact same chemical structure as all other glucose -"blood sugar" -influenced by amount of carbohydrates ingested, ability of body to metabolize carbs, circulating insulin levels.
Sucrose
-Glucose + fructose -This is the granulated table sugar and cane sugar with which most people are familiar.
Lactose
-Glucose + galactose -This is sugar found only in dairy products
Maltose
-Glucose + glucose -This is not generally found in foods, but is an intermediate breakdown of complex starch. -Found in molasses -Found in sweeteners found in processed food products
Sucrase breaks down into
-Glucose and fructose
Polysaccharides - Starch
-Glucose units linked by alpha bonds -Starch is the most significant polysaccharide in human nutrition -the storage form of carbohydrates for plants -Composed of many glucose molecules linked together with alpha bonds -During digestion, alpha bonds are broken to yield individual glucose molecules. -Cereals and grains -Legumes -Vegetables -Fruits
Polysaccharides - Fibers
-Glucose units linked by beta bonds -Individual molecules of fiber are bound together with beta bonds. -Unlike starch, humans, do not have the necessary enzymes to break apart the beta bonds. -fiber is indigestible but still plays an essential role in maintaining and promoting health. -Cellulose -Hemicellulose -Lignin -Algal Polysaccharides -Beta-glucans -Gums -Mucilages -Pectins
Which saccharide is classified as a disaccharide?
-Maltose -Sucrose -Lactose
Galactose
-Monosaccharide -Formed from the digestion of lactose -derived from the sugars in dairy products.
Glucose
-Monosaccharide -the most basic of the simple carbohydrates and the primary fuel for cells -generally crated from the breakdown of other carbohydrates -Can be found in corn syrup; commonly processed in foods.
Fructose
-Monosaccharide -the simple carbohydrate found in fruits and honey
What actions are functions of carbohydrates in the human body?
-Providing dietary fiber -Sparing protein breakdown -Providing the body's energy
Maltase breaks down into
2 glucose molecules
What is the dietary reference intake (DRI) per day for carbohydrates for adults?
225-325 grams
Which food choice provides complex carbohydrates?
Beans
Which food would be the best example of a disaccharide food source?
Beet Sugar
What is the difference between blood glucose and glycogen?
Blood glucose is the carbohydrate circulating in the body, and glycogen is the carbohydrate stored in the body.
Which statement best describes blood glucose?
Blood glucose is the same monosaccharide as the glucose found in food sources.
What is the preferred source of energy for cells in the human body?
Carbohydrates
Which carbohydrate most efficiently adds important bulk to the diet?
Cellulose
Which term represents the actual breakdown of substances resulting from the production and/or storage of gastric and digestive secretions?
Chemical digestion
Which statement concerning dietary fiber provides the best foundation for consumption of dietary fiber to help address constipation?
Dietary fiber adds bulk to fecal matter, stimulating muscle action in the intestine.
Lactose, or milk sugar, is classified as which type of carbohydrate?
Disaccharide
Which statement best describes the relationship between dietary fiber and glucose levels?
Eating dietary fibers may help slow the absorption of glucose by my body.
The body can digest and metabolize carbohydrates to produce which substance for energy?
Glucose
Lactase breaks down into
Glucose and galactose
Which statement about the classification of carbohydrates and their importance in nutrition is correct?
Glucose, fructose, and galactose are all monosaccharides, which are important in human nutrition.
Which component is a storage form of carbohydrates in humans?
Glycogen
How does the body use glycogen?
Glycogen is stored in the muscles and liver and then broken down into glucose for quick energy resources.
What is the purpose of glycogen?
Glycogen is stored in the skeletal muscles and liver for quick release to help the body maintain blood glucose levels.
Which food would be the best example of a monosaccharide food source?
Honey
Which statement correctly characterizes an aspect of chemical digestion?
Humans are not able to break down all polysaccharides through the process of chemical digestion.
which common sugar found outside of plants promotes the absorption of calcium and phosphorus?
Lactose
Which food would provide a source of soluble fiber?
Legumes
Which statement best describes mechanical digestion?
Mechanical digestion is the process of physically breaking down food into smaller particles.
Which class of carbohydrates is considered the building blocks of all carbohydrates?
Monosaccharides
Which statement represents the classifications of carbohydrates?
Monosaccharides and disaccharides are simple carbohydrates, whereas polysaccharides are complex carbohydrates.
Where does carbohydrate digestion begin?
Mouth
Which food would be the best example of a polysaccharide food?
Oats
Which statement outlines the functions of carbohydrates?
Provide energy, spare proteins, and provide dietary fiber
The parotid glands secrete an enzyme that acts on starch to begin its breakdown into dextrins and disaccharides. What is this called?
Ptyalin
Which statement about saliva is accurate?
Saliva contains amylase, an enzyme that begins the process of digesting starches.
Why is segmentation needed within the gastrointestinal tract to complete digestion?
Segmentation helps with mechanical digestion by increasing the breakdown of food particles for chemical digestion.
Which structure is the storage form of carbohydrates in plants?
Starch
Which statement best describes the only real nutrient function of carbohydrates?
The only real nutrient function of carbohydrates is the supply of energy.
How does the pancreas participate in the chemical digestion of carbohydrates?
The pancreas secretes pancreatic amylase, which splits carbohydrates in the small intestine
What does peristalsis most resemble?
Wavy, rippling motion