Wednesday, October 8, 2008

Key terms of Concept 6l1

Organelle: Part of a cell with a specific function.

Plasma membrane: Thin outer boundary of a cell that regulates the traffic of chemicals between the cell and its surroundings.

Nucleus: In an atom, the central core that contains protons and neutrons in a cell, the part that houses the cell’s genetic material in the form of DNA.

Cytoplasm: Region of a cell between the nucleus and the plasma membrane.

Cell wall: Strong wall outside a plant cell’s plasma membrane that protects the cell and maintains its shape.

Prokaryotic cell: Cells lacking a nucleus and most other organelles.

Eukaryotic cell: Cells with a nucleus and other internal organelles.

Diffusion: Net movement of the particles of a substance from where they are more concentrated to where they are less concentrated.

Equilibrium: Point at which the number of diffusing molecules moving in one direction is equal to the number moving in the opposite direction.

Selectively permeable membrane: Membranes that allows some substance to pass more easily than others and blocks the passage of some substance altogether.

Tuesday, September 9, 2008

Review Chapter 5

1. C
2. B
3. C
4. B
5. B
6. D
7. B

8. You will consume carbohydrates.

9. They are all different kinds of carbohydrates and they are all sacchardies.

10. One type sends chemical signals to your body and the other type make the appearance of man and woman different which is testosterone.

11. Because polypeptide is a chain that makes up to Protein. Basically, polypeptide builds protein. That’s why it’s related.

12. It affects the protein’s ability because it changes the function of protein like egg changes in to solid form from liquid because of the temperature change.

14.
a. It’s water molecule H2O because two monomers joined together and forming a polymer needs process called dehydration reaction. So you can see the molecule that come apart should water molecule.

b. It’s called dehydration reaction because to form a polymer, there should at least two monomers joined together and the process of joining is called dehydration reaction. During the dehydration reaction, the water molecule falls apart. Like the diagrams up here shows water molecule falling apart. So it’s dehydration reaction.

c. It will be added to the side where H or OH is.

15
a. At 38 degrees, enzyme A performs the best and at 78 degrees, enzyme B performs the best.
b. Enzyme A= human. Enzyme B= thermophilic bacteria.
c. It’s because that catalysts of enzyme starts to slow down at the temperature 40 degrees.

Sunday, September 7, 2008

Summary for chapter 5.5

Enzymes are Proteins that speed up specific reactions in cells

Enzymes and Activation energy
Activation energy is a start energy level to start chemical reaction. To provide activation energy level, is to heat up the reactants because hotter molecules can collide with enough energy to weaken bonds.
Another way to reach activation energy level, is to depend on catalyst, burn compounds that speed up the chemical reactions. One of the special catalysts are called enzymes.
Enzymes help reactants to have chemical reaction at it's normal temperature.

How enzymes work
Enzymes also depends on the substance called substrate. It fits into a particular region of the enzyme, called the activate site. It weakons bonds and help to break a bond and have a chemical reaction. Another way is that enzymes can lower the activation energy but accepting two reactant molecules.

1. Activation level is a level that chemical reaction can start and enzymes helps to start chemical reaction by raising activation level.

Summary for chapter 5.4

The functions of proteins
A protein is a polymer constructed from a set of 20 kinds of monomers called amino acids. It functions almost every organisms on earth. It structure our hair, muscles, and circulate our blood and defend our body from harmful microorganisms.

Amino Acids
Amino acid monomers consists of a central carbon atom bonded to four partners. One partner is hydrogen atom and two other atom s are carboxyl group. The side group is called as the 'R-group' is responsible for the particular chemical properties of each amino acid. Other side group is hydroxyl so it attracts water.

Building a Protein
Cell create proteins by linking amino acids together into a chain called a polypeptide. Like creating polumer chain, each link is created by dehydration reaction. There are 20 kinds of monomers that forms protein channel.

1. Hair, fur, muscles etc.

Summary for Chapter 5.3

Characteristics of Lipids
Lipids are hydrophobic which means water fearing. The reason why oil can't mix with water is because oil is consists of lipids. Those lipids can circulate our body chemical signals to cells. Some other types of lipids are knowsn as fats store energy inb our body.

Fats
Fats consists of a three-carbon backbone glycerol attached to three fatty acids, which contain long hydrocarbon chains. Some of them are solid at room temperature and some of them are liquid at room temperature(oils). They store energy for later use but if you don't use, you might have some problems by having too much of them
Saturated Fats is a fat in which all three fatty acid chains contain the maximum possible number of hydrogen atoms. Most of them are animal fats and they are solid at room temperature.
Unsaturated fats contains less fatty acid chains because some of its carbon atoms are double-bonded each other. Vegetables, fruits and fishes are unsaturated. Too many saturated reduce blood flow and cause it to heart disease.

Steroids
A lipid molecule in which the carbon skeleton forms four fused rings is a Steroids. They are lipids because they are hydrophobic but what they function is different from fats. Fats store energies for your body but steroids send chemical signals to our body.
One type of steroids is called Cholesterol. It's an essential molecule found in the membrances that surround your cells. It also helps to produce other steroids but it has high levels of particular cholestrol-containing substance tht risks hear diseases.

1. ?

2.?

3. Steroids don't store energies and it sends chemical signals to your body.

4. It shows to buyers that this food is healthy because it has no bad fats.

Monday, September 1, 2008

Summary for 5.1








Carbon is the main ingredient of organic molecules

~carbon skeletons and functional groups
-Carbon only has 4 electrons on it's highest energy so they bond with other atoms
-The carbon-based molecules are organic molecules
-the non carbon-based molecules are inorganic molecules.
-organic molecules that are composed of carbon and hydrogen is hydrocarbons
-hydrocarbons are important in our lives
-A group of atoms within a molecule that interacts in predicatble was with other molecules are called a functional group
-Organic molecules have many shapes like strasight chain, single, double and tripple bond


~Monomoers and Polymers
-monomers is composed of large molecules, that are built from many simillar, smaller molecular units.
-The cell link monomers together into long chains called polymers
-Polymers take important role in our life and ion environment and you will find various kinds of polymers that are built from a collection of fewer that 50 kinds of monomers -Four important large molecules are carbohydrates, lipids, proteins, nucleic acid.


~Building and breaking polymers
-building polymer can be called is dehydratioon reaction because when you form a chain, you remove water from it





Concept check





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.




Monomers are small molecule units and when these monomers link to each other, they became polymers. Polymers are straight chains of mnomers. So many monomers in straight chain=polymers.




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




Water molecule is released during the construction of a polymer.




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




Summary for the 5.2

Carbohydrates provide fuel and building material

Sugars
A carboohydrate is an organic compound made up of sugar molecules. It contains carbond, hydrogen and oxygen in the ratio of C1:H2:O1.(CH2O)
Monnosaccharides are simple sugar contain just one sugar unit (Glucose). These type of sweet sugars are well known to us like honey. Glucose exists in both straight-chain and ring-shaped forms.
Sugars molecules are the main supporter of cellular work. How it work is that, cells break down their stored glucose molecules and extract energy from it. But if there are too much glucose or not used immediatetly, it became fat molecules.
Using the dehydration reaction, cells construct a disaccharide or "double sugar" from two monosaccharides. The sucrose, the most common disaccharide molecule, it consists of a glucose molecule linked to a fractose molecule.

Polysaccharides
Long polymer chains made up of simple sugar monomers are called polysaccharides, or complex carbohydrates. For example, starch is a polysaccharide found in plant cells that consists entirely of glucose monomers. It's chain branch and coil up like the loops of a telephone cord. It's like stockpiles. Everything needs sugar to work, humans digest sugars within thier digestive systems.
Animal cells do not contain starch. Instead, animals such as turkeys (and humans) store excess sugar in the form of a polysaccharide called glycogen. It's like starch, is a chain of many glucose monomers. In humans, it's stored in granules in liver and muscle cells. When body needs energy, it break downs and release glucose.
Cellulose, served as building materials. They protect cells and stiffen the plant, preventing it from flopping over. Like starch and glycogen, cellulose is also made up of glucose monomers.
Most living thins can't digest cellulose. So, cellulose from plants foods, commonly referred to as"fiber", passes unchanged through your digestive system. It helps your digestive system healthy but it's not a nutrient.
All most all carbohydrates are hydrophilic. It's because there are many hydroxyl groups in thier sugar units. So monosaccharides and disaccharides solute for water. But cellulose and some form of starch aren't solute of water.

1. Monosaccharide is is a simple sugar that contain only one sugar unit but disacchride have double sugar from two monosaccharide.

2, All these three are consist of glucose molecules. But starch is found in plant cells and glycogen is chain of glucose monomers, more highly branched then starch, and stored in our liver and muscle cells. Cellulose is consist of glucose molecules but what it does is different and it's chain is linked to hydrogen bonds.

Thursday, August 28, 2008

The Presense Of The Biology Lord


Hi!

My name is Yong an Jun and I'm freshman. As you know I'm Korean and this is my second year in AISG.

My hobby is playing computer game called Starcraft and Warcraft. I can't stop saying that Blizzard (game makers) company is genius. Holy, you really should play this game. Also it's a sports of Korea. This should be added to Olympic. First of all Starcraft is about 20 years old in Korea.

The place I go every weekend is internet cafe. We Koreans go to internet cafe almost every week. This is our way to release our stress. Oh this is additional thing but you should remember that I'm the best Starcraft, Warcraft and DOTA player in 9th grade.

For my personality, some people think that I'm full of curelity, but I'm actually not so don't think about that. I don't watch any bloody movies or cruel games.

My knowledge toward science is not wide and professional. And for Biology, this is the first time to touch with Biology. But that doens't means that I don't have any interests toward science and biology. I like science and I like to learn new things.