K101 Practice Exam 1 Review Flashcards

Vocabulary practice flashcards covering fundamental chemistry, cellular biology, biomolecules, functional groups, and chemical bonds based on K101 Practice Exam 1.

Ionic Bond

A chemical bond formed by the transfer of electrons between a metal and a non-metal.

Covalent Bond

A chemical bond formed by the sharing of electrons between non-metals.

Hydrogen Bond

A non-covalent, electrostatic bond where a slightly positive hydrogen atom attached to an $\text{O}$, $\text{N}$, or $\text{F}$ atom is attracted to a slightly negative atom.

Sodium Chloride ($\text{NaCl}$)

An ionic compound formed by electron transfer between a metal (sodium) and a non-metal (chlorine).

Biological Significance of Hydrogen Bonds

They hold water molecules together and provide water with its life-sustaining physical and chemical properties.

Three Domains of Life

The biological classification system consisting of Archaea, Bacteria, and Eukarya, which excludes non-living entities like viruses.

Rabies Virus

An infectious viral agent that does not belong to any of the three domains of life.

Archaea

A domain of single-celled prokaryotic organisms typically found in extreme environments such as Yellowstone Park hot springs.

Yellowstone Park Hot Springs

An example of an extreme environment where Archaea organisms are most likely to be found.

Valence Electrons of C, N, O, and H

Carbon, Nitrogen, Oxygen, and Hydrogen have 4, 5, 6, and 1 valence electrons, respectively.

Carbon Valence Electrons

Carbon has 4 valence electrons.

Boron Formation from Carbon

Removing one proton from a carbon atom (atomic number 6) converts it into a boron atom (atomic number 5).

Carbon Isotopes

Variants of carbon such as Carbon-12 and Carbon-13 that maintain 6 protons but differ in neutron count.

Mass Number Calculation for Argon

An argon isotope with 18 protons and ~21 neutrons has a mass number of ~39, calculated by adding protons and neutrons.

Mass Number Formula

The total number of nuclear particles in an atom, calculated as $\text{Mass Number} = \text{Protons} + \text{Neutrons}$.

Plasma Membrane in Prokaryotes and Eukaryotes

A cellular boundary structure shared by both prokaryotic and eukaryotic cells, meaning it is not a major structural difference between them.

Compartmentalized Organelles

Membrane-bound internal structures that represent a major difference between eukaryotic cells and prokaryotic cells.

Polar Covalent Bond in Water

The chemical bond holding oxygen and hydrogen atoms together within a single $\text{H}_2\text{O}$ molecule.

Basic Solution

A solution with a pH value greater than 7, such as a solution with a pH of 10.

Acidic Solution

A solution with a pH value less than 7, such as a solution with a pH of 2 or 5.

Neutral pH Solution

A solution with a pH value of 7, representing equal concentrations of hydronium and hydroxide ions.

Hydronium Ion ($\text{H}_3\text{O}^+$ or $\text{H}^+$)

The acidic ion species formed during the auto-ionization of water, technically representing a hydrogen proton.

Hydroxide Ion ($\text{OH}^-$)

The basic anion formed during the auto-ionization of water.

Amphoteric Nature of Water

The property of $\text{H}_2\text{O}$ that allows it to act as either a weak acid or a weak base.

Density of Solid $\text{H}_2\text{O}$

Solid $\text{H}_2\text{O}$ (ice) is less dense than liquid $\text{H}_2\text{O}$, allowing ice to float on water.

Base Requirement for Neutralization

A solution with a lower pH (e.g., pH 2) contains a higher concentration of $\text{H}^+$ ions and therefore requires the most base to reach pH 7.

Molar Concentration of $\text{H}^+$ at pH 5

A solution with a pH of 5 has a hydrogen ion concentration $[\text{H}^+] = 10^{-5}\,\text{M} = 0.00001\,\text{M}$.

pH Determination from $[\text{OH}^-]$

A solution with $10^{-9}\,\text{M}$ $[\text{OH}^-]$ has $10^{-5}\,\text{M}$ $[\text{H}^+]$, which corresponds to a pH of 5.

pH vs. pOH

pH measures hydrogen ion concentration $[\text{H}^+]$, while pOH measures hydroxide ion concentration $[\text{OH}^-]$.

Solvent Properties of Water

Water functions as an excellent solvent primarily due to the collective pull of its hydrogen bonds and polar molecular nature.

High Specific Heat of Water

A thermal property of water that helps organisms and environments minimize temperature fluctuations.

Evaporative Cooling

A mechanism powered by water's high heat of vaporization that assists in minimizing temperature fluctuations.

Hydroxyl Group ($\text{-OH}$)

A polar functional group characteristic of alcohols such as ethanol.

Ethanol

An alcohol molecule containing a hydroxyl ($\text{-OH}$) functional group.

Sulfhydryl Group ($\text{-SH}$)

A functional group characteristic of thiols such as methanethiol.

Methanethiol

An organic compound containing a sulfhydryl ($\text{-SH}$) functional group.

Dehydration Synthesis

A chemical reaction in which two molecules are joined together to form a polymer while producing a new water molecule.

Hydrolysis

A reaction that breaks down polymers into smaller monomers through the addition of water molecules.

Peptide Bonds in Biological Macromolecules

Covalent bonds that specifically link amino acids together in proteins, not present in carbohydrates or lipids like sugar and butter.

Steroids

A category of non-glycerol lipids that includes biological signaling molecules such as testosterone and estradiol.

Testosterone and Estradiol

Examples of steroid hormones that belong to the non-glycerol lipid class.

Secondary Protein Structure

Structural patterns in proteins resulting from backbone hydrogen bonding, specifically standard alpha helices and beta folding.

Purine

A class of double-ring nitrogenous bases including adenine and guanine.

Pyrimidine Base Characteristics

Single-ring nitrogenous bases such as cytosine and thymine that engage in C-T or C-G pairing.

Carboxyl Group ($\text{-COOH}$)

A polar, acidic functional group consisting of a carbonyl and hydroxyl group.

Peptide Bond Rule for Amino Acid Chains

The number of peptide bonds in a linear protein chain is calculated as the number of amino acids minus 1 ($n - 1$).

79

How many peptide bonds are in 80 MINO ACIDS

Qualities Conferring Water Solubility

Functional group characteristics that promote solubility in water, specifically being polar or charged.

Ribose Ring in RNA

The five-carbon sugar in RNA nucleotides that possesses two hydroxyl ($\text{-OH}$) groups.

RNA ($\text{Ribonucleic Acid}$)

A nucleic acid distinguished by having two $\text{-OH}$ groups attached to its ribose sugar group.

Phosphodiester Bond

The covalent bond that links nucleotide monomers together along a nucleic acid chain.

Phospholipid

An amphipathic molecule with hydrophilic heads and hydrophobic tails, making it ideal for cell membrane structure.

Saturated Fatty Acid

A fatty acid chain containing no double bonds between carbon atoms, resulting in maximum hydrogen saturation.

Structure of Butter

A lipid composed of saturated fatty acids containing no double bonds.

Triglyceride Structure

A macromolecule composed of one glycerol molecule linked to three fatty acid chains.

Auto-Ionization of Water

The reaction in which water molecules spontaneously dissociate into hydronium ions ($\text{H}_3\text{O}^+$) and hydroxide ions ($\text{OH}^-$).

Alpha/Beta Folding

The characteristic folding pattern (alpha helices and beta sheets) defined as secondary protein structure.

Methylamine

An organic compound containing an amine group ($\text{-NH}_2$), distinct from hydroxyl ($\text{-OH}$) or sulfhydryl ($\text{-SH}$) compounds.

Propionaldehyde

An aldehyde compound containing a carbonyl group, distinct from alcohols and thiols.

Heat of Vaporization in Water

The high amount of energy required to convert liquid water into gas, contributing to temperature stabilization via evaporative cooling.