Chapter 5.2 Summary

A carbohydrate is an organic compund made up of sugar molecules. Sugars contain the elements carbon, hydrogen, and oxygen in the ratio of 1 carbon: 2 hydrogen: 1 oxygen. Simple sugars contain monosaccharides. Glucose exists in straight-chain and right-shaped forms. Sugar molecules are the main fuel supply for cellular work. Cells break down glucose molecules and extract their stored energy. Using the dehydration reaction, cells construct a disaccharide. The most common disaccharide is sucrose. It consists of a glucose molecule linked to a fructose molecule. Long polymer chains made up of simple sugar monomers are called polysaccharides. Starch is a polysaccharide found in plant cell. Plant cells need sugar for energy to perform work, and for building other molecules. Animal cells do not contain starch, animals such as turkeys store excess sugar in the form of a plysaccharide called glycogen. Glycogen is a chain of many glucose monomers but a glycogen polymer is more highly branched than a starch polymer. Some polysaccharides in plants, such as cellulose, serve as building materials. They protect cells and stiffen the plant, preventing it from flopping over. Cellulose is made up of glucose monomers. Multiple cellulose chains are linked together with hydrogen bonds. Cellulose from the plant foods, commonly referred to as "fiber," passes unchanged through your digestive system. It helps keep your digestive system healthy, but it doesn't serve as a nutrient. Almost all carbohydrates are hydrophilic. It's due to the many hydroxyl groups in their sugar units.

Concept Check 5.2
1. Explain the difference between a monosaccharide and a disaccharide. Give an example of each.
Monosaccharides are simple sugars contain just one sugar unit and disaccharide is sugar with two monosacchrides. Glucose is an example of monosaccharides and sucrose is an example of disaccharide.

2. Compare and contrast starch, glycogen, and cellulose.
Starch is a polysaccharide found in plant cells that consists entirely of glucose monomers. Glycogen is polysaccharide in animal cells that consists of many glucose monomers. Cellulose is polysaccharide consisting of glucose monomers that reinforces plant-cell walls.

3. How do animals store excess glucose molecules?
Animals store excess sugar in the form of a polysaccharide called glycogen.

Chapter 5.1 summary

- Carbon can form bonds with one or more other carbon atoms, producing an endless variety of carbon skeletons.

- Most carbon-based molecules are classified as organic molecules.

- Non-carbon-based molecules are classified as inorganic molecules.

- Organic molecules that are composed of only carbon and hydrogen are known as hydrocarbons.

- Methane is one of the most abundant hydrocarbons in natural gas, a fuel used to heat homes.

- Functional group is a group of atoms within a molecule that interacts in predictable ways with other molecules.

- Hydrozyl groups are hydriophilic, meaning they attract water molecules.

- Monomer is small molecular unit that is the building block of a larger molecule.

- Polymer is long chain of small molecular units.

- Life's large molecules are classified into four main categories: carbohydrates, lipids, proteins, and nucleic acids.

- Each time a monomer is added to a chain, a water molecule is released and it's called a dehydration reaction.

- Organisms build polymers and also break them down.

- Cells break bonds between monomers by adding water to them and it's called a hydrolysis reaction.

- Water is removed to build a polymer, and water is added to break it down.

1. Draw a molecule that has a three-carbon skeleton and a hydroxyl group on the middle carbon.

2. Explain the connection between monomers and polymers.

Large molecules are built from many similar, smaller molecular units called monomers and your cells link monomers together into long chains called polymers.

3. What molecule is released during construction of a polymer? What is this reaction called?

monomers, hydrolysis reaction.

4. Draw at least three ways in which five carbon atoms could be joined to make different carbon skeletons.

I don't know

About me

Hey, I'm Eunseol but you can call me Lilly.
I'm from South Korea and moved to China when I was a 5th grader.
I went to cliffrod Internation School and then I went to the states.
I like hanging out with my friends and me and my friends do anything to have fun.
I love parties and I do all the crazy stuff that you could ever imagine.
I'm not a serious person and I might be a little immature for my age.
I don't like awkward moments and absolutely hate drama.
I'm pretty much nice to everybody unless they hate me.
I like meeting new people, so get to know me?

Peace out :)