DNA Part 1
A human space explorer crash-lands on a planet where the native inhabitants are entirely unable to digest glycogen, but are able to digest cellulose. Consequently, they make their clothing out of glycogen-based material. The starving space explorer eats one of the native inhabitants’ shirts and the natives are amazed. Based on this information which of the following is/are true?
I. The explorer can digest a-glycosidic linkages.
II. The native inhabitants can digest a-glycosidic linkages.
III. The native inhabitants can digest starch.
A. I only
B. I and III only
C. II and III only
D. I, II, and III
A
What are the (2) types of purines in DNA?
guanine and adenine
The cells in your body are constantly undergoing cellular respiration, producing CO2 as a byproduct. What would happen to the pH of your blood if you were to hold your breath?
A. It would increase.
B. It would be the same.
C. It would decrease.
D. It cannot be determined with the information provided.
C
Name (3) R-group characteristics that can influence shape.
Hydrogen bonding, ionic bonding, disulfide bonds, Van Der Waals interactions, hydrophilic vs. hydrophobic, positive vs. negative charge
In our strawberry lab, what substance is the final step to separate the DNA from other materials?
ice-cold ethanol
What is the monomer of DNA?
nucleotide
You found that there is a 15% composition of adenine in a sample of DNA. What are the percent compositions of guanine, thymine, and cytosine?
guanine = 30%
thymine= 15%
cytosine = 30%
What is the monomer of a protein?
amino acid
What are the (2) main bond types found in the quaternary structure of proteins?
hydrogen and disulfide
Should the distance between (2) strands of DNA be consistent throughout the double helix? Why?
Yes
purines combine with pyrimidines
What is found on the 1' end of deoxyribose in DNA?
nitrogenous base
What is the charge of DNA? How do we know?
negative, on backbone in phosphate group
What bond holds the monomer of proteins together? What is the most basic structure level of a protein?
peptide bonds
primary
Will an enzyme lower or raise the activation energy?
Lower
What does it mean for DNA to be antiparallel?
5' --> 3' on one side and 3' --> 5' on the other
In what order can DNA nucleotides be added?
DNA nucleotides can only be added on the 3' end hydroxyl group
Who discovered the double helix? What method did they use to see it?
Watson, Crick, Franklin
X-ray diffraction
What are the components of an amino acid?
amino group, carboxyl group, R-group (side chain), central carbon atom
What are cofactors typically aided the reaction speed of? Coenzymes?
metal ions
organic molecules
When using a microscope, how do you put it away properly?
by going to lowest setting, lowering the stage all the way down, and using both hands to put away.
What type of bonds are found between the nitrogenous bases? The backbone? How many bonds are between A-T and C-G?
hydrogen
phosphodiester
2
3
Draw a DNA model. Include: (5) nucleotides per strand, base pairing, hydrogen bonds, phosphodiester bonds, and 5' and 3' directions.
Can check drawings on DNA powerpoint
Compare and contrast the alpha helix and the beta pleated sheets. What bonds are found in these structures?
Alpha helix (a-helix): The C=O of the carboxyl group in one amino acid is hydrogen bonded to a H from an amino group. Polypeptide chain is pulled into a helix. R-groups stick outward
Beta-pleated sheet: A polypeptide chain lines up and makes sharp turns to form sheet. Held together by hydrogen bonds formed between the C=O and N-H (amino). Can be parallel. Can be antiparallel. R-group extends above and below the sheet
Hydrogen bonds
Draw an example of competitive inhibitor and noncompetitive inhibitor. Include labels of the substrate and enzyme.
Drawing can be checked on proteins powerpoint.
What do you use if you are unable to view a specimen through the lens of a microscope? What do you do if you break a slide?
use a cleansing wipe
inform teacher and they will place in broken glass.