Carbohydrates (IB Topic B1.1)

Essential Idea(s): Compounds of carbon, hydrogen and oxygen are used to supply and store energy. Both carbohydrates and lipids have a structure that is well adapted for their specific functions.

Unit Length: 3 Lessons (No AHL content)

  Guiding Questions

◊ In what ways do variations in form allow diversity of function in carbohydrates and lipids?

◊ How do carbohydrates and lipids compare as energy storage compounds?

IB Statement(s) and Objective(s)

B1.1.1: Chemical properties of a carbon atom allowing for the formation of diverse compounds upon which life is based

  • Describe a covalent bond
  • Outline the number and type of bonds carbon can form with other atoms
  • Define organic (chemistry)
  • List the four major classes of carbon compounds used by living organisms
  • NOS Concept: Scientific conventions are based on international agreement

 

B1.1.2 and B1.1.3: 

Production of macromolecules by condensation reactions that link monomers to form a polymer

Digestion of polymers into monomers by hydrolysis reactions

  • Define anabolism, catabolism, monomer, and polymer
  • Describe condensation (aka dehydration synthesis) reactions
  • Describe hydrolysis reactions
  • Using simple shapes to represent monomers, diagram a condensation reaction
  • Given diagrams, identify common examples of organic polymers

 

B1.1.4: Form and function of monosaccharides

  • State the generalized chemical formula of carbohydrates
  • Given molecular diagrams, recognize pentoses and hexoses as monosaccharides
  • Explain how the form of glucose fits its function in living organisms

 

B1.1.5 and B1.1.6:

Polysaccharides as energy storage compounds

Structure of cellulose related to its function as a structural polysaccharide in plants

  • Describe the use of glucose polymers for energy storage in living organisms
  • Describe how the structure of cellulose fits its function as a structural polysaccharide
  • Identify the origin, structure, and describe the function of: glycogen, amylose, and amylopectin

 

B1.1.7: Role of glycoproteins in cell–cell recognition

  • Define glycoprotein
  • Outline the function of glycoproteins
  • Define antigen
  • Outline the function of ABO antigens as an example of glycoproteins
  • Outline the difference between the ABO blood antigens
  • Describe the consequence of mismatched blood transfusions, including agglutination and hemolysis
Activities: = podcast / = inquiry 5 / = Write it Ӕ = The academy  / = Read it

Ӕ: The Academy – Carbs & Lipids (💁)

Go here if you need help screen recording videos

Grab a tablet (or a pen + paper), and screencast a Khan Academy-style video of yourself drawing the molecules from B1.1. This video should include ALL of the following

  • You drawing a ribose molecule
    • Include correct numbering of carbons (1-5)
  • You drawing an 𝝰-glucose molecule
    • Briefly state how glycogen and starch would form from this
    • Briefly state difference between 𝝰- and 𝛃-glucose
  • You drawing the formation of a disaccharide from 2 monosaccharides
    • Include definition of anabolism 
    • Include explanation of condensation reactions
    • Briefly outline the breakdown of this; including definition of catabolism and hydrolysis
  • You drawing a saturated or unsaturated fatty acid
    • Show how these fatty acids come together in both triglycerides and phospholipids 

 

/: The Truth about Carbs and Calories (💁/ 👫max 3)

From Atkins to Keto, carbs have been at the center of countless diet fads. Some diets declare war on carbs, and keep them out of the diet as much as possible. Is this accurate? Are carbs healthy or unhealthy? Listen to this podcast, then come up with some key inquiry questions to discuss the topic. Here are a few suggestion to get you started: 

  • What macromolecules are in whole grains that makes them different from processed grain?
  • How whole grains vs. processed grains ultimately affect blood sugar in humans?

 

/ (+NOS / +TOK): Death of Trans Fats at 107 – One of those times When Science Got it Wrong (💁/ 👫podcast max 3)

Anyone over the age of 10 has likely consumed trans fats in their life, thinking they were healthy. And why not? When they were first invented, trans fats seemed like a great solution: they greatly helped prevent spoilage of food products, and they tasted just like normal fats. But scientists kept on asking questions, and ultimately the truth was revealed: trans fats are really, really bad for human health. Read this article and respond: 1) What makes trans fats different from unsaturated and saturated fats?  2) Why trans fats are bad for human health; and 3) What do you think about the idea of “science getting it wrong” – should we be more skeptical of science? Should we wait to put new science into practice? Why or why not?

 

/ (+NOS): How to be a Savvy Consumer of Science News (💁/ 👫max 3)

It’s easy to get confused about science in the 21st century. Throughout the world, scientists churn out papers at breakneck speed, and journalists try to interpret them with catchy “spitball” headlines. How can you know what is true and what is just clickbait? Listen to the podcast and answer: 1) How the process of science often gets misunderstood from scientist → journalist → public;  2) How the science on saturated fats has been a big player in this confusing realm; and  3) How everyday people can best know which science articles to trust, and which to disregard.  

 

Extras

Puzzle: Evaluating Scientific Claims (💁/ 👫 max 2)

Print out these pages, and cut out the individual statements in the second box (try to disregard the current positioning – they are already in the correct spots). Place the individual statements inside the correct column/row. 

 

📄(Old School Worksheet): Practice with Carbohydrates 

Complete this worksheet for extra practice with carbohydrates, and this one on lipids. These will both help make you a pro on the topic!