Biochemistry

1. What is the difference between an endergonic and an exergonic reaction?
In metabolism, exergonic occurs in catabolism and releases energy while endergonic occurs in anabolism and consumes energy.

2. How many protons, electrons, and valence electrons does Na+ have? (the atomic number for sodium is 11)
Protons: 11
Electrons: 10
Valence electrons: 8

3. What is the difference between an ionic bond, a covalent bond, and a hydrogen bond? Which is strongest? Weakest?
Ionic bond is the attraction between two oppositely charged ions, usually between a metal and nonmetal. Covalent bond is the sharing of two elections to form pairs. Hydrogen bond is the bonding of hydrogen to an electronegative atom.
Strongest: Covalent bond
Weakest Hydrogen bond

4. What are the four types of organic macromolecules and which monomers link together to make up each?
The four types of organic macromolecules: polysaccharides, lipids, nucleic acids, polypeptides
Monomers: carbohydrates, fatty acids,nucleotides, amino acids -respectively

5. Which type of bond holds together the monomers that make up the four primary organic macromolecules?
Covalent bonds

6. Which type of bonds hold together two complementary strands of DNA?
Hydrogen bonds

7. Why do phospholipids form micelles in water?
The non-polar ends, which are the tails mix together while the phosphate heads, polar ends, form to come in contact with the surrounding water.

8. What is the difference between a saturated and an unsaturated fatty acid?
Saturated fatty acid has more hydrocarbons linked in the chain, while unsaturated fatty acid have carbon doubled bonded to another carbon, reducing the amount of hydrogen in the chain.

9. Often times science fiction stories make reference to silicon-based life forms as opposed to carbon-based life. Why does this make sense as a plausible possibility for alien life?
In the periodic table, silicon is in the same column as carbon, with the same valence electrons; therefore, they have the ability to bond with many other elements including itself (possible backbone for life).

10. What are the three differences between DNA and RNA?
Adenine pairs with Thymine in DNA, Uracil in RNA
Sugar backbones deoxyribonucleic vs. ribonucleic acid
RNA is one-stranded, DNA is double-stranded

11. What are the five nitrogenous bases that form the eight nucleotides that make up RNA and DNA?
Guanine
Cytosine
Adenine
Thymine
Uracil

12. How do nucleotides fit together to form DNA? (draw it!)
Combination of phosphate and sugar as the backbone in the sequence of phosphate-sugar-phosphate-sugar-phosphate-etc. (ie. the sides of the ladder), and one of the 4 nitrogenous bases (G, C, A, T) connected to a sugar backbone complimentary to their pair of nucleotide (half of the horizontal ladder step).

. .
S - A = T - S
. .
P P
. .
S - C = G - S
. .
P P
. .
S - G = C - S
. .
P P
. .
S - T = A - S
. .

P = Phosphate
S = Sugar
(A, T, G, C) = Nitrogenous bases ( Adenine, Thymine, Guanine, Cytosine)

13. What causes proteins to fold into their final shape?
The characteristics of their reactive group

14. What is the difference between a protein’s primary structure, secondary structure, tertiary structure, and quaternary structure?
The shape; linear -> helical/sheet-> 3D

15. What causes the structural shape of receptors to change?
The interaction of the right molecule with the right receptor.

16. What would happen if an enzyme were absent from a cell?
The reaction would still occur, but the reactions would not occur at a useful rate (not enough activation energy).

17. What would happen if a cell had too much of a particular enzyme?
Either the reaction process will speed up or completely shut off.

18. Why are enzymes highly specific for their substrates and receptors highly specific for their ligands?
Each has a unique shape and arrange for the active site so they can bind correctly

19. Based on its name, what do you think proteases do? (Hint: these are also called peptidases)
I think proteases have to be something to do with polypeptides, either breaking down or synthesis.

Science Article 1

When aging, we all have a tendency to unfortunately recieve potential life-risking conditions, especially towards the crowd of senior citizens. Thus, there were studies to see that if physical activity can provide beneficial statistics on behaviors and the physical beings of a group. The study was conducted variously (both had controlled and random assignments), and tested to see if they got the end result they wanted was. However, the data on some aging conditions may have been different if their sampling size were different. Overall, physical activity showed that it reduced a large number of problems of health, but a small percent still remain.

http://www.sciencedaily.com/releases/2010/01/100125172946.htm

About Me

Hi, my name is Eric. I'm a quiet and passive guy, but once I get to know somebody, I can be pretty outgoing type. I'm a first year in college attending both Ventura and Oxnard College and trying to cram my classes together so I can transfer quickly. In academics, I have steady grades, usually average to a couple of A's, mostly B's and one or two C's.

So, why am I taking biology? It's basically for my GE's and I picked biology over the other courses, because when I took it in high school, I thought the subject interesting, but I never got to understand it well, so it's a good chance for me to retake the course. I'm not taking the lab portion, so hopefully I won't be confused. Biology to me is one of those intense reading-the-book courses, however I can never find myself to focus reading, so hopefully I'll pass!