reproduction

Component that distinguishes the cell wall of Gram-positive bacteria from Gram-negative bacteria,Thick peptidoglycan layer and teichoic acids.

Structural characteristic of Gram-negative bacterial cell walls absent in Gram-positive cells,Outer membrane containing lipopolysaccharides ($LPS$).

Specific substance in Mycobacteria cell walls that necessitates acid-fast staining,Mycolic acids.

Constituents of a virus's genetic material,"Either $DNA$ or $RNA$, but never both."

Enzyme used by retroviruses to synthesize $DNA$ from an $RNA$ template,Reverse transcriptase.

The specific target cell of the Human Immunodeficiency Virus ($HIV$),$CD4^{+}$ T cells.

Term for a virus that specifically infects bacterial cells,Bacteriophage.

Bacteriophage life cycle characterized by immediate replication and host cell destruction,Lytic cycle.

Bacteriophage life cycle where viral $DNA$ integrates into the host genome without immediate lysis,Lysogenic cycle.

Intracellular signaling molecule increased by Cholera toxin to trigger $Cl^{-}$ secretion,Cyclic $AMP$ ($cAMP$).

Mechanism of action of the Botulinum toxin at the neuromuscular junction,It blocks the release of Acetylcholine ($ACh$).

Primary effect of Tetanus toxin on the nervous system,It blocks the release of inhibitory neurotransmitters.

Evolutionary theory suggesting mitochondria and chloroplasts originated from bacteria,Endosymbiotic theory.

Sedimentation coefficient of ribosomes found within mitochondria and chloroplasts,$70S$.

Primary method of reproduction in prokaryotic organisms,Binary fission.

The three primary mechanisms of horizontal gene transfer in bacteria,"Transformation, transduction, and conjugation."

"Circular, extra-chromosomal $DNA$ molecules in bacteria often carrying resistance genes",Plasmids.

Specific bacterial structure targeted by Penicillin to inhibit growth,Peptidoglycan crosslinking in the cell wall.

Specific target of bacterial ribosome inhibitors,The $70S$ ribosome (composed of $50S$ and $30S$ subunits).

Composition of prions,Infectious proteins containing no nucleic acids.

Composition of viroids,Infectious naked $RNA$ molecules that primarily affect plants.

Distinction between 'antigenic drift' and 'antigenic shift' in viruses,"Drift involves small mutations, while shift involves genome reassortment leading to pandemics."

Genome type of the $SARS-CoV-2$ virus,Positive-sense $RNA$.

Original biological function of the $CRISPR-Cas9$ system in bacteria,An adaptive immune system used to defend against viral infections.

Direction in which $DNA$ polymerase reads the template strand,$3' \rightarrow 5'$.

Direction in which $DNA$ polymerase synthesizes a new $DNA$ strand,$5' \rightarrow 3'$.

Enzyme responsible for sealing nicks between Okazaki fragments,$DNA$ ligase.

Coding characteristic of eukaryotic $mRNA$ compared to prokaryotic $mRNA$,"Eukaryotic $mRNA$ is monocistronic, while prokaryotic $mRNA$ is polycistronic."

Primary eukaryotic enzyme responsible for synthesizing $mRNA$,$RNA$ polymerase II.

Length of Okazaki fragments in eukaryotic cells,$100$–$200$ base pairs ($bp$).

Length of Okazaki fragments in prokaryotic cells,$1000$–$2000$ base pairs ($bp$).

The standard start codon and the amino acid it encodes,"$AUG$, which codes for Methionine ($Met$)."

The three universal stop codons,"$UAA$, $UAG$, and $UGA$."

Phenomenon allowing flexible base pairing at the third position of a codon,Wobble hypothesis.

Sedimentation coefficient of the functional eukaryotic ribosome,$80S$ (composed of $60S$ and $40S$ subunits).

Term for catalytic $RNA$ molecules,Ribozymes.

Sequence required for the initiation of translation in prokaryotes,Shine-Dalgarno sequence.

Sequence required for the initiation of translation in eukaryotes,Kozak sequence.

Amino acids that are highly concentrated in histone proteins,Lysine and Arginine.

Function of Histone $H1$,It acts as a linker histone to stabilize the nucleosome structure.

Transcriptional status of euchromatin vs heterochromatin,"Euchromatin is transcriptionally active, while heterochromatin is dense and inactive."

The physical diameter of the $DNA$ double helix,$2$ $nm$.

The number of base pairs contained in one full turn of the $DNA$ helix,$10.5$ $bp$.

The specific amino acid substitution in Sickle-cell anemia,Glutamate ($Glu$) is replaced by Valine ($Val$) in the $\beta$-globin chain.

Mechanism of mutation in Huntington’s disease,$CAG$ repeat expansion.

Mechanism of mutation in Fragile X syndrome,$CGG$ repeat expansion.

Definition of $V_{max}$ in enzyme kinetics,The maximum velocity of an enzymatic reaction at saturating substrate concentrations.

Definition of the Michaelis constant ($K_{m}$),The substrate concentration at which the reaction velocity is half of $V_{max}$.

Effect of a competitive inhibitor on $K_{m}$ and $V_{max}$,"$K_{m}$ increases, but $V_{max}$ remains unchanged."

Effect of a noncompetitive inhibitor on $K_{m}$ and $V_{max}$,"$V_{max}$ decreases, but $K_{m}$ remains unchanged."

Optimal $pH$ for the protein-digesting enzyme pepsin,Approximately $2$.

Optimal $pH$ for the pancreatic enzyme trypsin,Approximately $8$.

Thermodynamic parameter that enzymes cannot change,Gibbs free energy change ($\Delta G$).

Primary mechanism by which enzymes increase reaction rates,By lowering the activation energy.

Protein tag used to signal the degradation of proteins by the proteasome,Ubiquitin.

Primary source of $NADPH$ in the cell,The Pentose Phosphate Pathway ($PPP$).

Total net $ATP$ yield from the complete oxidation of one palmitate ($C16$) molecule,$106$ $ATP$.

Net products of glycolysis from one molecule of glucose,"$2$ $ATP$, $2$ $NADH$, and $2$ pyruvate."

Net energy products of the Krebs cycle per molecule of glucose,"$2$ $ATP$, $6$ $NADH$, and $2$ $FADH_{2}$."

Final electron acceptor in the mitochondrial electron transport chain,Oxygen ($O_{2}$).

The specific wavelength absorbed by Photosystem II,$680$ $nm$.

The specific wavelength absorbed by Photosystem I,$700$ $nm$.

Energy requirements of the Calvin cycle to produce one molecule of glucose,$18$ $ATP$ and $12$ $NADPH$.

"Process where Rubisco binds to $O_{2}$ instead of $CO_{2}$, reducing photosynthetic efficiency",Photorespiration.

Source of the oxygen gas ($O_{2}$) produced during photosynthesis,Water ($H_{2}O$).

Normal $pH$ range of human arterial blood,$7.35$–$7.45$.

Average total blood volume in a healthy human adult,Approximately $5$ $L$.

Comparison of oxygen affinity between fetal hemoglobin ($HbF$) and adult hemoglobin ($HbA$),$HbF$ has a higher oxygen affinity than $HbA$.

Description of the Bohr effect,High $CO_{2}$ or $H^{+}$ concentrations decrease hemoglobin's affinity for $O_{2}$.

Description of the Haldane effect,The oxygenation of hemoglobin promotes the dissociation of $CO_{2}$.

Relative binding strength of carbon monoxide ($CO$) to hemoglobin compared to $O_{2}$,$CO$ binds approximately $200$ times more strongly than $O_{2}$.

Shape of the oxygen dissociation curve for myoglobin,Hyperbolic.

Shape of the oxygen dissociation curve for hemoglobin,Sigmoidal.

Average lifespan of a red blood cell,Approximately $120$ days.

Normal range for white blood cell ($WBC$) count per microliter,$5000$–$10000$ /$\mu L$.

Only class of immunoglobulin ($Ig$) capable of crossing the placenta,$IgG$.

"Primary class of immunoglobulin found in bodily secretions (saliva, tears, breast milk)",$IgA$.

Class of immunoglobulin primarily involved in allergic reactions and parasitic defense,$IgE$.

Distribution of $MHC$ $I$ molecules in the human body,Found on all nucleated cells.

Distribution of $MHC$ $II$ molecules in the human body,Found only on antigen-presenting cells ($APCs$).

Standard resting membrane potential of a neuron,$-70$ $mV$.

Threshold potential required to trigger an action potential,$-55$ $mV$.

Stoichiometry of the $Na^{+}/K^{+}$ pump,"$3$ $Na^{+}$ ions out, $2$ $K^{+}$ ions in."

Type of nerve impulse conduction that occurs at the Nodes of Ranvier,Saltatory conduction.

The major inhibitory neurotransmitter in the brain,GABA.

The major inhibitory neurotransmitter in the spinal cord,Glycine.

The primary excitatory neurotransmitter in the central nervous system,Glutamate.

Subunit of troponin that binds to calcium ions to initiate muscle contraction,Troponin $C$.

Protein that physically blocks the myosin-binding sites on actin at rest,Tropomyosin.

Essential molecule required for the detachment of the myosin head from actin,$ATP$.

Functional structures present in cardiac muscle but absent in skeletal muscle,Intercalated discs and gap junctions.

The volume of air inspired or expired during a normal breath at rest,Tidal volume (approx. $500$ $mL$).

The maximum amount of air that can be expired after a maximum inspiration,Vital capacity (approx. $4.5$ $L$).

The volume of air remaining in the lungs after a forced expiration,Residual volume (approx. $1.2$ $L$).

Primary method of $CO_{2}$ transport in the blood,"As bicarbonate ions ($HCO_{3}^{-}$), accounting for $70\%$ of transport."

Function and cellular source of pulmonary surfactant,Lowers alveolar surface tension; secreted by type II pneumocytes.