Tuesday 9 September 2008

Chapter 5 Review pg.106-107 #1-12,14,15

1) c. water
2) d. glycogen
3) c. hyphilic
4) b. lipid
5) b. side groups
6) d. substrate
7) b. lowers the activation energy of a reaction
8)
9) They all consists of sugar.
10) Steroids are a lipid molecule in which the carvon skeleton forms four fused rings. It circulates in your body as chemical signals and cause some differences in appearance between men and women.
11) Polypeptide is a chain that creates protein by linking amino acids toghter.
12) It heats up unfolded proteins since the most of the forces that maintain folding are weak attractions between pairs of side groups, and between side groups and water.
14) a.
b. dehydration reaction
c. OH
15) a. 38 degrees for enzyme A and 78 degrees for enzyme B.
b. Enzyme A from bacteria and enzyme B for humans.
c.

Thursday 4 September 2008

Summary 5.5

-activation energy is a starting energy

-enzymes are the main catalysts of chemical reactions.

-catalysts speed up chemical reactions.

-enzymes does not supply activation energy but instead, it lowers the energy requirement barrier that reaction is resulted in normal cell temperature.

-a specific reactant acted upon by an enzyme is enzyme's substrate.

-sustrate fits into a region called active site.

-fit between sustrate and enzyme is not rigid.

-way that an enzyme can lower activation energy is by accepting tow reatant molecules in do adjacent sites.

-like proteins, enzyme's shape is senstive to changes in its environment.



Concept Check 5.5
1.Explan the role of activation energy in a reaction. How does an enzyme affect activation energy?
Activation energy is a start up energy tat activates reactant. It is the main catalyst of te reaction.
2.Describe how a substrate interacts with an enzyme.
If it fits into a region of the enzymes called active site. the region changes shape for it to fit.



Wednesday 3 September 2008

Summary 5.4

-protein is a polymer constructed from a set of 20 kinds of amino acids.

-proteins circulate in the blood and defend the body from harmful microorganisms and other act as signal, sending messages from one cell to another.

-each amino acid, a cetral carbon atom bonded to four partners, three central carbon's partners are same in all amino acids and one is hydrogen atom

-the difference for each amino type is the side group

-side group of amino acid are leucine, a hydrocarbon, attracts water.

-polypeptide is making amino acids into a chain

-a protein's shape is influenced by the environment, aqueous.

-process called denaturation is used when protein is heated.



Concept Check 5.4



1.Give at least two examples of proteins you can "see" in the world around you. What are their functions?

Hair and muscles. Hair makes animas to keep in temperature and their muscles make them strong.

2.Relate amino acids, polypeptides, and proteins.

Protein is polymer made from 20 kinds of monomers which is amino acids. Amino acid pairs the central carbon atom with four partners and linking them into a chain is polypeptide.

3.Expain how heat can destroy a protein.

The heat uses a process called denaturation which means heat denatures protein and makes it into a solid.

4. Which parts of an amino acid's structure are the same in all amino acids? Which part is unique?

They are all responsible for particular chemical properties of each amino acids and each type of amino acid is attached to the fouth bond of the central carbon.

Summary 5.3

-lipid molecules circulate in your body as chemical signals to cells


-lipids are fats stored in body


-some fats are solid in room temperature.


-carbon atoms in the fatty acid chains form single bonds with each other and rest bond with hydrogen atoms


-the fats in fruits, vegetables, and fish are unsaturated fat.


-saturated fats are unhealthy so it can cause heart disease.


-four focused rings in which the carbon skeletons forms is steroid.


-steroids are lipids because they are hydrophobic but different from fats structure and fuction.


-cholesterol is the best known steroid in.


-high cholesterol increases risk for cardiovascular disease.


Concept Check 5.3

1.What property do lipids share?

Water avoiding property like oil's.

2.What are the parts of a fat molecule?

The parts of a fat molecule are saturated fat and unsaturated fat.

3.Describe two ways that steroids dffer from fats.

Fats consist of a three-carbon backbone attached to three fatty acids. The carbon skeleton which forms four focused rings is steroids.

4.What does the term unstaturated fat on a food label mean?

Having less than the maximum number of hydrogen atoms.

Tuesday 2 September 2008

Summary 5.2

-sugars contain the elements carbon, hydrogen and oxygen, ratio of 1:2:1
-at the core of most sugar molecules found in nature are carbon skeletons that have a ring shape
-carbohydrate is an organic compound made up of sugar molecules
-simple sugars contain one sugar unit, monosaccharides eg) glucose, frutose and glactose.
-glucose exist in both straight chain and ring shaped forms

-sugar molecules, glucose are main supply for cellular work.

-cells break down glucose molecules and extract their stored energy (mostly not used immediately incorporated into larger carbogydrate)

-disaccharide, cell constructed by two monosaccharide.

-sucrose can be broken down into glucose and frucose and used right away. Body can store these after use.

-sucrose consist of a glucose molecule linked to fuctose molecule.

-when plants break down starch molecules, the stored glucose becomes available.

-humans and animals use plant starch for digestive system

-glycogen mostly stored in liver and muscle cells

-when body needs energy it breaks down glycogen and release glucose.

-cellulose and some of starch are not soluble.

Concept Check 5.2

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

Monosaccharide is one sugar unit and disaccharide is two sugar unit. Glucose, fractrose, and glactose are example of monossacharide and sucrose is an example of disaccharide.

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

Starch is a polysaccharide found in plant cell, glycogen is polysaccharide found in animals and cellulose is aso polysaccharides in plant that serves building materials.

3.How do animals store excess glucose molecules?

Animals store excess glucose molecules in a form of polysaccharide.

Summary 5.1




-carbon atom is a connecting point from which other atoms can branch off in up to four directions.



-carbon can form bonds with one or more other carbon atoms producing variety of skeletons.
-carbon based molecules are classified as organic molecules.
-noncarbon based molecules are classified as inorganic molecules(water, oxygen, etc)
-molecules only composed of carbon and hydrogen is hydrocarbons(natural gas, fuel used for heating homes)
-two other atoms frequently found in organism molecules are oygen and hydrogen.

-the carbon skeleton and the attached functional groups dermine the properties of an organic molecule.
-hydrophilic attracts water molecules.
-a polymer can be the chain of monomers like train and the cars attached.
-polymers are built by about 50 monomers
-life's large molecules are carbonhydrate, lipids, proteins and DNA(nucleic acids)
-when water molecule is released, a monomer is added to the chain.
-must break polymers to make monomers available to cell.



Concept Check 5.1



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





2.Explain the connection between monomers and polymers.

Large molecules that are built from many similar, smaller units are monomers and cells linked monomers into long chain is polymer so inorder to be a polymer, cells linked monomers are needed.

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

Water molecule is released and the reaction is called dehydration reation.

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