Biochemistry Nutrition- Introduction
You are what you eat!
Over the next few days, we will be learning about the various biocompounds (aka organic macromolecules) that are required to build the cells of every organism on Earth. These are the organic macromolecules that YOU are built from. It makes sense then that these are also the same molecules we typically eat. We eat for lots of reasons, but a really important one is that we need raw ingredients to build more cells and tissue so that we can grow as well as repair damaged tissue.
The four types of biocompounds we will be studying are:
-Carbohydrates -Lipids -Proteins -Nucleic Acids
You've probably heard of the first three, but the fourth one may be a new term. Nucleic acids include DNA, so while you won't see them listed on a nutrition label, you eat them every time you eat another organism. And let's face it.. almost everything we eat comes from another organism. Hamburger? Cows. Bacon? Pigs. Bread? Wheat plants. Salad? Lots of plants. Mmmm.. DNA.
Over the next few days, we will be learning about the various biocompounds (aka organic macromolecules) that are required to build the cells of every organism on Earth. These are the organic macromolecules that YOU are built from. It makes sense then that these are also the same molecules we typically eat. We eat for lots of reasons, but a really important one is that we need raw ingredients to build more cells and tissue so that we can grow as well as repair damaged tissue.
The four types of biocompounds we will be studying are:
-Carbohydrates -Lipids -Proteins -Nucleic Acids
You've probably heard of the first three, but the fourth one may be a new term. Nucleic acids include DNA, so while you won't see them listed on a nutrition label, you eat them every time you eat another organism. And let's face it.. almost everything we eat comes from another organism. Hamburger? Cows. Bacon? Pigs. Bread? Wheat plants. Salad? Lots of plants. Mmmm.. DNA.
Activity 1: Identifying foods that are rich in each of the biocompounds.
Many foods contain more than one type (some even include all four) of the organic macromolecules. With a peer, brainstorm some of the foods you think contain a lot of each of the following three biocompounds, then click on the compound to see a list of sample foods.
Carbohydrates
Lipids
Protein
Carbohydrates
Lipids
Protein
Activity 2: Determining calories in each biocompound.
Nutrition labels give us lots of information about the food that we eat. Take a look at this info graphic to familiarize yourself with each part of a nutrition label, then scroll down to the next instruction.
Notice the total calorie count highlighted in yellow. We refer to the number of "calories" in our food, but that term is a little misleading. A calorie is a measure of energy stored in a molecule and is actually a very small amount of energy. In most countries of the world, nutrition labels include total Kilocalories (KCal). This means a food that is 5 KCal is actually 5,000 calories! In America, we use the word Calorie in place of Kilocalories. This nutrition label says 250 total calories which means this food actually has 250,000 calories according to scientists. For the purposes of this class, we'll use the American definition of calorie as found on nutrition labels.
Each type of macromolecule contains a specific number of calories:
Every single gram of carbohydrate contains 4 calories. These are listed on the nutrition label as Total Carbohydrates.
Every single gram of protein contains 4 calories.
Every single gram of lipids contain 9 calories. These are actually listed on the nutrition label as Total Fat.
Notice that the fatty foods that contain lipids have a much higher total calorie count (in most cases) because lipids can store so much energy. This will be an important concept in this unit.
Every single gram of protein contains 4 calories.
Every single gram of lipids contain 9 calories. These are actually listed on the nutrition label as Total Fat.
Notice that the fatty foods that contain lipids have a much higher total calorie count (in most cases) because lipids can store so much energy. This will be an important concept in this unit.
Challenge: How many total calories per serving would be in a food that has 5 grams of carbohydrates, 5 grams of protein, and 3 grams of lipids? Scroll down for the answer once you've made your guess...
.
.
.
.
.
.
.
.
.
Did you guess 67 calories per serving? You are correct! Pretty easy, right? Well, there is one more detail we need to discuss.
Notice on the nutrition label that under Total Carbohydrates, there are some specific types of carbohydrates listed. As humans, we are actually unable to digest Fiber so we can't actually count the grams of fiber in our total calorie count. Those fiber molecules still contain energy, we just don't have the ability to get it out. We'll talk more about the importance of fiber later in this unit.
So, let's look at the previous challenge but now we'll give you more information:
So, let's look at the previous challenge but now we'll give you more information:
How many total calories would be in a serving of food that contains 5 grams of carbohydrates (but 2 of those grams are actually fiber), 5 grams of proteins, and 3 grams of lipids? Scroll down once you have a guess.
Activity 3: Practice calculating total calories for the following three nutrition labels. Once you have calculated the three totals, see your teacher to make sure your calculated totals are the correct answer.
|
|