General Overview - Nutrients and Digestion Flashcards
What is a nutrient?
A substance that has a useful function when taken into your body.
What are macronutrients, and can you give examples?
Nutrients required in relatively large amounts. Examples include carbohydrates, lipids, proteins, and nucleic acids.
What is the general formula for carbohydrates?
Cn(H2O)n.
What are monosaccharides, and can you name three examples?
Monosaccharides are single sugars with the formula C6H12O6. Examples include glucose, fructose, and galactose.
What is lactose intolerance?
A condition where people lack the enzyme lactase and cannot break down lactose (milk sugar).
What are proteins made of?
Proteins are made of long chains of amino acids. There are 20 different amino acids, 9 of which are essential and must be obtained through diet.
What is denaturation in proteins?
The permanent change in the 3D shape of a protein, which causes it to lose its function.
What are triglycerides composed of?
One glycerol molecule and three fatty acid chains.
What is the difference between saturated and unsaturated fats?
Saturated fats have only single bonds between carbon atoms (C-C), while unsaturated fats have at least one double bond (C=C).
What are enzymes, and what do they do?
Enzymes are proteins that catalyze chemical reactions in the body by lowering activation energy.
What are the two models of enzyme activity?
The Lock & Key model and the Induced Fit model.
How does temperature affect enzyme activity?
Enzymes function best at an optimal temperature (37°C for humans). High temperatures can denature enzymes, while low temperatures reduce their flexibility and activity.
What is competitive inhibition in enzyme activity?
It occurs when a molecule similar in shape to the substrate binds to the enzyme’s active site, preventing the substrate from binding.
What is digestion?
The process of breaking down large, complex organic molecules into small particles that can be absorbed and utilized by the body’s tissues.
What are the four components of digestion?
Ingestion, Digestion, Absorption, and Egestion.
What are the two types of digestion?
- Physical Digestion: Mechanical process of breaking down food. 2. Chemical Digestion: Enzymes break down food through hydrolysis.
What are the accessory organs involved in digestion?
Salivary glands, liver, pancreas, gall bladder, and endocrine glands.
What enzymes are involved in the digestion of proteins?
Proteases such as pepsin, trypsin, chymotrypsin, and peptidases.
What role does the small intestine play in digestion?
It is the major site of digestion and absorption of macromolecule subunits.
What are the three sections of the small intestine?
Duodenum, Jejunum, and Ileum.
What is the function of bile in digestion?
Bile emulsifies fats, increasing the surface area for lipase to break down fats.
What are villi and microvilli, and what is their function?
Villi and microvilli are small finger-like projections in the small intestine that increase the surface area for absorption.
How are carbohydrates digested in the small intestine?
Carbohydrates are broken down by enzymes like amylase, maltase, sucrase, and lactase into simple sugars such as glucose, fructose, and galactose.
What is the role of the pancreas in digestion?
The pancreas releases enzymes like proteases, amylase, and lipase, as well as bicarbonate ions to neutralize stomach acid.
What are the two main functions of the large intestine?
Absorption of water and minerals, and concentration and elimination of waste.
