Exam 1 Review - General Biology & Physics Concepts

Flashcards covering atomic structure, thermodynamics, chemical bonds, biomolecules, protein structure, and laws of motion from the Exam 1 Review.

Neutron Count Calculation in Neutral Atoms

Subtract the atomic number ($Z$) from the mass number ($A$) using the formula: $\text{Neutrons} = A - Z$.

Primary Driving Force Behind Chemical Bond Formation

Atoms interact to achieve maximum stability by acquiring a full outer electron shell, typically following the octet rule.

Factors Determining Kinetic Energy Magnitude

An object's kinetic energy depends directly on its mass and the square of its velocity, expressed as $KE = \frac{1}{2}mv^2$.

Second Law of Thermodynamics and Heat Flow

Thermal energy spontaneously transfers from hotter objects to colder objects, increasing the total entropy of the universe.

Role of Water in Hydrolysis Reactions

A water molecule ($\text{H}_2\text{O}$) is consumed to split a covalent bond holding monomers together within a polymer.

Structural Property Allowing Phospholipids to Form Bilayers

Their amphipathic nature, featuring hydrophilic phosphate heads and hydrophobic fatty acid tails.

Bohr Model Electron Shell Capacities

The innermost energy level holds up to $2$ electrons, while the second energy level holds up to $8$ electrons.

Anabolic Role of Dehydration Synthesis

It joins individual monomers together into larger polymers while producing water as a byproduct.

Universal Product of Polymerization via Condensation

A small molecule, typically water ($\text{H}_2\text{O}$), is eliminated for each covalent bond established between monomers.

Functional Groups Involved in Peptide Bond Formation

The carboxyl group ($\text{-COOH}$) of one amino acid binds with the amino group ($\text{-NH}_2$) of another.

Distinction Between Atomic Number and Atomic Mass

Atomic number reflects only proton count, whereas atomic mass represents the combined total of protons and neutrons.

Cause of Partial Charges in Polar Covalent Bonds

Unequal sharing of bonding electrons due to a significant difference in electronegativity between the bonded atoms.

Condition Required for an Atom to Have No Net Electrical Charge

The total number of positively charged nuclear protons must exactly equal the total number of orbiting electrons.

Newton's Third Law Principle

When one object exerts a force on a second object, the second object exerts an equal force in the opposite direction on the first.

Concept of Inertia

The inherent tendency of an object to resist changes in its state of motion unless acted upon by a net external force.

Structural Cause of Diverse Protein Functions

The precise arrangement of distinct amino acid side chains determines a unique $3\text{D}$ folding pattern suited for specific functions.

Effect of Carbon-Carbon Double Bonds on Lipid Fluidity

Double bonds introduce kinks that prevent hydrocarbon chains from packing tightly, lowering the melting point and keeping oils liquid at room temperature.

Molecular Cause of High Surface Tension in Water

Cohesive hydrogen bonds formed between adjacent polar water molecules at the liquid surface.

Molecular Basis of Hydrophilic Dissolution

Polar or charged substances readily form hydrogen bonds or electrostatic interactions with polar water molecules.

Forces Stabilizing Tertiary Structure

Interactions among amino acid R-groups, including hydrogen bonds, ionic bonds, hydrophobic interactions, and disulfide bridges.

Consequence of Disrupting Side Chain Interactions

The tertiary level of protein structure destabilizes and unfolds without changing the primary amino acid sequence.

Driving Force of the Hydrophobic Effect

Water molecules exclude nonpolar molecules to maximize their own cohesive hydrogen bonding, forcing nonpolar groups to aggregate.

Bonds Responsible for Primary Protein Structure

Strong covalent peptide bonds linking amino acids in a linear sequence.

Stabilizing Bonds in Secondary Protein Structure

Hydrogen bonds formed between oxygen and hydrogen atoms along the polypeptide backbone, creating $\alpha$-helices and $\beta$-sheets.

Requirement for Quaternary Structure Formation

The functional aggregation of two or more separate polypeptide subunits into a multi-unit protein complex.

Structural Impact of Cis-Double Bonds in Fatty Acid Chains

They create a persistent bend in the hydrocarbon tail, reducing intermolecular packing and maintaining membrane fluidity.

Thermodynamic Meaning of Entropy Increase

Energy naturally degrades into less organized, highly dispersed thermal forms, increasing system randomness.