Nutrition And Digestive System Flashcards
Define Nutrients
A substance found in food that’s used by the body to meet important needs.
Nutrients are simple molecules (nutritional substance) that can be used directly by the cells
The 6 important nutrients
Proteins
Carbohydrates
Fats
Water
Vitamins
Minerals
Carbohydrates (3)
- Made of sugar molecule or a chain of sugar molecules
- The body’s main energy source
- 3 types (monosaccharides, disaccharides, polysaccharides)
Monosaccharides
Carbohydrates made of simple sugars (ex: glucose)
Disaccharides
Carbohydrates made of double sugars (ex: lactose)
Examples of monosaccharides & disaccharides (5)
Fruits, pastries, sweets, fruit juice, carbonated drinks
Polysaccharides
Carbohydrates made of complex sugars (ex: starch)
Ex foods: cereals, breads, pasta, potatoes, rice, legumes, tapioca
Fats (6)
- composed of fatty acids and a glycerol
- synonym for lipids
- store and provide energy (longer period (weeks, months) compared to carbohydrates)
- building blocks of hormones and cell membranes
- protect organs and insulate the body from the cold
Ex: cholesterol, vegetable oils, butter, fatty meats, fish, eggs, nuts, croissants, French fries
Types of fats
Saturated, unsaturated, trans
Saturated fats (6)
- unhealthy
- straight fatty acid
- solid fat at room temperature (usually for oils)
- packed very tightly
- can cause heart disease
Ex: butter, coconut oil, crisco
Unsaturated fats (4)
- good fats
- kinked fatty acid
- liquid fat at room temperature
- bent molecules
Trans fat (4)
- bad fats
- made by adding hydrogen and a lot of pressure to vegetable oil
- stiffer fat
- can lead to clog arteries
Proteins (4)
- Large molecules made of chains of amino acids
- build and repair cells and tissues
- provide body with energy after carbohydrates and fats
Ex: meat, fish, eggs, milk, cheese, legumes, tofu, nuts
Water (5)
- transports nutrients and waste products in the body
- Helps regulate the body temperature and needed for chemical reactions in the body
- 70% of the human body
- 2 to 3 L of water a day
Ex: fruits, fruit, juices, vegetables, vegetable juices, soups, milk
Vitamins (4)
- small amounts
- Different functions (contributing to chemical reaction, helping to make energy, helping to fight off infections, helping to repair tissue)
- Main types: A, B1, B2, C, D and E
Ex: fruits, vegetables, dairy products, whole grains, eggs
Minerals (4)
- 4% of the weight of the human body
- Different roles (building, tissue, maintaining fluid in the body, helping muscles to contract, transporting oxygen in the blood)
- minerals: Potassium, calcium, magnesium, phosphorus
Ex: dairy products, legumes, seafood, fish, fruits, vegetables
Function of dietary fibre
Prevent constipation
The energy value of nutrients
Carbohydrates: 17 kJ/g
Fats: 36 kJ/g
Proteins: 17 kJ/g
Vitamins, minerals, dietary fiber, and water: 0
Benedict test
Turns blue to green to orange if positive
Monosaccharides: simple sugars, like glucose or fructose
Disaccharides: lactose and maltose
Lugol
Turns dark purple in the presence of starch
Polysaccharides (complex carbohydrate)