Biochem Exam 1 Questions and
Answers Graded A+
What happens to enzymes when the temperature slightly increases within an optimal range?
The enzyme activity increases as the kinetic energy of molecules rises, allowing more
frequent collisions between enzyme and substrate.
Why do hydropho...
Biochem Exam 1 Questions and
Answers Graded A+
What happens to enzymes when the temperature slightly increases within an optimal range?
✔✔ The enzyme activity increases as the kinetic energy of molecules rises, allowing more
frequent collisions between enzyme and substrate.
Why do hydrophobic amino acids tend to cluster together in the center of a protein?
✔✔ To avoid contact with water, stabilizing the protein's structure.
What is the significance of the "lock and key" model in enzyme action?
✔✔ It explains that enzymes are highly specific, fitting only certain substrates like a key fits into
a specific lock.
Why is it crucial for cells to maintain a balanced pH?
✔✔ To ensure that enzymes and proteins maintain their proper structure and function.
What role does cholesterol play in maintaining cell membrane integrity?
1
,✔✔ It provides fluidity and stability to the cell membrane, preventing it from becoming too rigid
or too fluid.
How does an enzyme lower the activation energy of a biochemical reaction?
✔✔ By stabilizing the transition state, making it easier for the reaction to proceed.
Why is the folding of proteins critical to their function?
✔✔ Proper folding creates the specific active sites and interaction points necessary for the
protein to perform its biological role.
What happens to fatty acids during beta-oxidation?
✔✔ They are broken down into acetyl-CoA molecules, which then enter the Krebs cycle for
energy production.
What is the role of coenzymes like NAD+ in metabolic pathways?
✔✔ They act as electron carriers, facilitating redox reactions and energy transfer.
Why is the structure of ATP highly suited for its role as an energy currency?
2
,✔✔ The high-energy phosphate bonds are easily broken, releasing energy for cellular processes.
What is the relationship between the primary structure of a protein and its final three-
dimensional shape?
✔✔ The sequence of amino acids in the primary structure dictates how the protein will fold into
its final shape.
Why do unsaturated fats remain liquid at room temperature, unlike saturated fats?
✔✔ The double bonds in unsaturated fats create kinks, preventing the molecules from packing
tightly together.
How does feedback inhibition help regulate metabolic pathways?
✔✔ The end product of a pathway inhibits an upstream enzyme, preventing overproduction and
conserving energy.
Why are phospholipids arranged in a bilayer in cell membranes?
✔✔ Their hydrophilic heads face outward, interacting with water, while hydrophobic tails face
inward, avoiding water.
3
, What is the importance of hydrogen bonds in maintaining the secondary structure of proteins?
✔✔ Hydrogen bonds stabilize the alpha-helices and beta-sheets, providing structural integrity to
the protein.
What is the consequence of a mutation in the active site of an enzyme?
✔✔ It may reduce or completely abolish the enzyme’s ability to bind to its substrate and catalyze
reactions.
Why does glycolysis occur in the cytoplasm rather than in an organelle like the mitochondrion?
✔✔ Glycolysis is an ancient pathway present in all living cells and evolved to function in the
cytoplasm.
What distinguishes a globular protein from a fibrous protein in terms of function?
✔✔ Globular proteins are typically involved in dynamic functions like catalysis and transport,
while fibrous proteins provide structural support.
How does allosteric regulation influence enzyme activity?
✔✔ Binding of a molecule at an allosteric site changes the enzyme’s shape, either enhancing or
inhibiting its activity.
4
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller ExcellentScores. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $11.99. You're not tied to anything after your purchase.