Biochem Final Exam (1)

Biochem Final Exam
All of the following are true of lipids EXCEPT: - CORRECT ANSWER-lipids are a
less efficient form of energy than carbs

Which of the following lipid types is used for energy storage? - CORRECT
ANSWER-Triglycerides

Which of the following is true of endocytosis - CORRECT ANSWER-Utilizes receptor
proteins

For Individual lipids in a membrane bilayer, _______ movement is unrestricted while
_______ movement is restricted. - CORRECT ANSWER-lateral, transverse

Which of the following is NOT a lipid/fat soluble vitamin? - CORRECT
ANSWER-Vitamin C

Circle all of the following lipids that are involved in cell signaling - CORRECT
ANSWER-Eicosanoids & Steroids

What are the three components of nucleotides? - CORRECT ANSWER-sugar,
nitrogenous base, phosphate

Which nitrogenous bases are purines and which are pyrimidines - CORRECT
ANSWER-purines: A G
Pyrimidines: C U T

List each of the four factors that contribute to the overall 3-D structure of nucleic
acids - CORRECT ANSWER-1. H-bonding
2. syn/anti
3. base stacking
4. sugar puckering

Chemical analysis for why Thymine is used for DNA and NOT Uracil. Or why uracil is
used in RNA and not DNA. - CORRECT ANSWER-Uracil is more reactive and less
stable than Thiamine because it has a methyl protecting it
DNA needs to be protected to secure genetic information and RNA needs to

Outline the key features of the fluid mosaic model for membrane structure. Include
types of lipids, proteins, movement, etc. - CORRECT ANSWER-- fluid: consists of
polypeptides that move laterally, but cannot flip across the bilayer transversely.
- The mosaic part refers to proteins embedded in the membrane some integral
(through the membrane) and some peripheral (one layer)

, - Domains consist of proteins, phospholipids, and steroids with close interactions
from lipid rafts, moving throughout the "fluid' as a unit

Compare and contrast DNA and RNA (sugar, bases, stability, etc.) - CORRECT
ANSWER-- DNA (deoxyribose) Thiamine, double stranded, one copy, more stable
- RNA (ribose) Uracil, single stranded, multiple copies, less stable
- BOTH: use A,G,C nucleotides and phosphodiester bondsB

steps of molecular cloning - CORRECT ANSWER-

Which AA is NOT a nucleophile - CORRECT ANSWER-Phenylalanine

A B-sheet is a secondary structure stabilized by what type of interactions? -
CORRECT ANSWER-H-bonds between two parts of a polypeptide so that those
segments are held together side by side.

Which of the following is NOT a characteristic of globular proteins? - CORRECT
ANSWER-highly repetitive in primary structure

What is the term used to describe the combination of an enzyme with its cofactor(s)?
- CORRECT ANSWER-

Which of the following compounds is an example of post-translational modified AA? -
CORRECT ANSWER-Phosphotyrosine

Which AA is NOT basic? - CORRECT ANSWER-Methionine

An A-helix is stabilized by what type of interactions? - CORRECT ANSWER-H-bonds
between peptide groups four positions along the polypeptide

Which of the following are examples of homopolysaccharides? - CORRECT
ANSWER-Amylopectin & Amylose

T/F: Proteins found in most living organisms are composed of just L-amino acids. -
CORRECT ANSWER-True

T/F: Proteins found in most living organisms are composed of just S-amino acids. -
CORRECT ANSWER-False there are also R amino acids

T/F: Lysine will have a net negative charge at pH 7. - CORRECT ANSWER-False
(has net positive charge: NH3+)

T/F: Carbohydrates found in most living are D- carbs - CORRECT ANSWER-True