Nutrition And Digestive System Flashcards
(51 cards)
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)
Biuret test
Turns purple when proteins are present
Proteins
Solution of potassium hydroxide and copper sulphate
Sudan Red Test
Fat, soluble dye
Concentrated spots of colour in a test tube
Lipids (fats)
Calories to energy
1 cal is equal to 4000 J of energy (4kJ)
Energy requirement
The amount of energy, a person need daily, depends on a variety of factors, like age, sex, weight, level of physical activity, and overall state of health
Adolescent girls: 1800 to 2400 cal a day
Adolescent boys: 2200 to 3200 cal a day