BIO452 Exam 1 Study Guide

Flashcards covering the key concepts in the BIO452 exam study guide related to cell biology, protein structure, enzyme function, and gene regulation.

What are the major steps of the Central Dogma?

DNA to RNA (transcription) to protein (translation).

Which enzyme is responsible for transcription in the Central Dogma?

RNA polymerase.

What major amino acid group does valine belong to?

Hydrophobic amino acids.

What level of protein structure is referred to as primary?

The sequence of amino acids in a polypeptide chain.

What bonds hold DNA strands together?

Hydrogen bonds between complementary base pairs.

Why do proteins fold into particular structures?

Proteins fold due to interactions like covalent bonds and noncovalent bonds.

What are protein domains and why are they important?

Domains are distinct structural units that confer specific functions and interactions.

What is the difference between covalent and noncovalent bonds?

Covalent bonds share electrons, while noncovalent bonds do not share electrons.

Which type of bond relates to affinity?

Noncovalent bonds.

What is a chemical reaction with a highly negative ∆G likely to favor?

The product side.

If two proteins have a very low dissociation constant, what does this indicate about their affinity?

They have high affinity for each other.

What defines cooperative binding in proteins?

Higher ligand concentration increases the affinity for other subunits.

How do enzymes lower activation energy?

By stabilizing the transition state of a reaction.

Where are co-repressors found during gene repression?

Attached to the repressor protein.

How does dimerization affect a transcriptional regulator's binding specificity?

It reduces the number of locations it binds to.

In an inducible operon, what causes the repressor to become inactive?

Binding of an inducer molecule to the repressor.

How do coactivators promote transcription?

By modifying chromatin to make DNA more accessible.

What are western blots used for?

To detect specific proteins in a sample.

What is one of the main methods for protein structure determination?

X-ray crystallography.

What is the principle of immunohistochemistry?

To visualize specific proteins in tissue sections.

How does cryo-electron tomography help visualize cells?

By providing a 3D structure from multiple angles.

What are the three types of cytoskeleton filaments?

Actin filaments, microtubules, and intermediate filaments.

What role do actin filaments play in muscle contraction?

They work with myosin.

What is the function of kinesin in cellular transport?

Transporting vesicles along microtubules.

How are clathrin-coated vesicles formed?

Through the assembly of clathrin proteins around the vesicle.

What is the relationship between GTP hydrolysis and microtubule instability?

GTP hydrolysis contributes to the dynamic instability of microtubules.

How do vesicles fuse with target membranes?

Through the interaction between SNARE proteins.

What is the size of a clathrin coat determined by?

The number of triskelions.

What is the function of protein phosphorylation?

To regulate protein activity.

What are biomolecular condensates?

Structures formed by proteins and RNA that concentrate in specific cellular regions.

What is the significance of nucleosome occupancy in gene regulation?

It affects regulator binding and transcription.

Which protein structure is altered during protein folding?

Tertiary structure.

What is the role of proteomics?

To analyze protein expression and interactions.

In Western blotting, what is the purpose of applying primary antibodies?

To bind to specific target proteins.

What does the law of mass action explain in relation to cells?

How the concentration of reactants and products affects reaction direction.

What type of binding curves do cooperative vs. noncooperative binding illustrate?

Cooperative binding shows a sigmoidal curve, while noncooperative binding is linear.

What is an example of a process each filament (actin, microtubules, intermediate) is involved in?

Actin: muscle contraction; Microtubules: mitosis; Intermediate filaments: structural support.