5.1 summary

=Carbon is the main ingredient of organic molecules=

*organic molecule=most carbon-bases molecules
*Inorganic molecule=Non-carbon-based molecules ex)H2O, O2, NH2

*Hydrocarbon=organic molecule that are composed of only carbon & hydrogen
*functional groups=group of atoms within a molecule that interacts in predictable ways with other molecules

*hydrophilic=functional group that attracts water

*monomers=large molecules that are built from many similar, smaller molecular units
*polymers=linked monomers together into long chains.

a polymer

Note=!

*Carbon skeletons and functional groups

-carbon> very common, has four partly-filled electrons in its highest energy level.
-Functional groups are important because carbon skeleton and the attached functional groups determine the properties of organic molecule

-Hydrocarbon=organic molecule that are composed of only carbon & hydrogen

-Hydrocarbons molstly used as fuel, gas.

ex) Methane(CH4).

-hydrophilic molecules(attract water molecules) such as hydroxyl groups tend to become surrounded by water molecules.

*Monomers and Polymers

-Bimolecules> composed of hundreds or even millions of atoms. Monomers create these.
-Polymers: the chains with monomers linked together.

-All different polymers are built from a collection of fewer than 50 kinds of monomers.

-Classification for life's large molecules: carbohydrates, lipid, proteins, and nuclei acids.

ex) spider's web is an example of polymer that is made out of protein

*Building and breaking polymers

Dehydratiion: two monomers bond to each other, making a polymer chain longer.

-Each time a monomer is added to a chain, a water molecule is released.

Ex) Hydroxyl group of one monomer reacts with a hydrogen atom from the other monomer releasing a water molecule eventually.

Hydrolysis: the addition of a water molecule breads the polymer chain.

-Our cells break down the monomers to obtain energy by adding a water molecule into it.

-Basicully water molecule has been removed to build a polymer

*Concept Check 5.1

1. Draw a molecule that has a three carbon skeleton and a hydroxyl group on the middle carbon (Hint: The molecule's fromula is C3H8O.)

-

2. Explain the connection between monmomers and polymers

-Polymers are the chain that is made of lots of monomers linked together and monomers are just one molecular units.

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

- a water molecule will be released and this reaction is called dehydration reaction

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

Chpater 5.2 summary

= Carbohydrates provide fuel and building material=

*Carbohydrate: an organic compound made up of sugar molecules.

Monosaccharides: a one sugar unite that sugars contain.

ex) glucose, fructose, and galactose
-Sugar molecules, particularly glucose, becomes stored energy by being broken by cells.
*Disaccharide: a double sugar made of two monosaccharidefromed by the dehydration. The most common disaccharide is surcrose made of a glucose monomer and fructose monomer. It is mainly found plants to nourish every part.

*Polysaccharides or carbohydrates: a long polymer chains made up of simple sugar monomers.

Starch, for an example, is sugar stockpiles. Plants break down starch moleculse, and use the stored glucose for energy. Ex) potatoes, rice, and corn
starch

Animal cells have glycogen instead of starch. Glycogen is a chain of many glucose monomers. Whenver body needs energy it breads down glycogens to release glucose.

*Cellulose is one of polysaccharides in plants. They are linked together with hydrogen bonds, forming fibers. Animals cannot digest cellulose because animals cannot bread down cellulose. Therefore, cellulose does not become nutrition for animals but it helps our digestion while being digested in our body without being broken.

*Carbohydrates are hydrophilic. It is because of the many hydroxyl groups in sugar units, so they dissolve easily in water but cellulose does not dissolve in water because they have large moleules.

*Concept Check 5.2

1. Explain the difference between a monosaccharide and a disaccharide. Give an example of each.

-Monosaccharide is a single sugar unit and glucose, fructose, and galactose are examples for it. Disaccharide is double sugar and sucrose is an example.

2. Compare and contrast starch, glycogen, and cellulose.

- Stache, glycogen, and cellulose are all polysaccharides and are made of glucose monomers. However, starch is found in plants and humans use the plant starch as food by breaking it down in their digestive systems. Glycogen is more highly branched than a starch. They are stored in liver and muscle cells for our energy. Cellulose, serving as building materials, protect cells and stiffen the plant.

3. How do animals store excess glucose molecules?

- Animals store glucose molecules in liver and muscle cells and whenever it is needed for energy, it breaks down and extract the stored energy.

Who Is The Biology DotA

Hi ! I am SangSin Lee, the Biology DotA.
I am Korean who goes to American International School of GuangZhou.
I have been in AISG for one year and this Gr.9 would be my second year.

Me, the best starcraft, warcraft, DotA player in Gr.9. I really like computer games.

Yong used to be the best player but he is now nothing to me. You want to challenge me? Go ahead. I accept the challenge whatever game it is.

Biology,, is very complicated thing and sometimes extremely hard to understand.

That makes me quite frustrated whenever I do not get the biological facts. However, sometimes the curiousity blows up my head. For example, how can those 100s elements make up the whole world. That means 100 kinds of different things created this whole universe. That DOESN'T made sense to me.

And why Biology DotA??
sorry, I cannot tell you the secret meaning inside of DotA.
If you guys are curious, you might want to get interested in Blizzard games.=))
Hope you find out.

Science is a mystery and Biology is just a part of the science....n.n