Molecular & Cellular Biology
This classic experiment by Meselson and Stahl proved that DNA replication is of this specific type.
What is semi-conservative
This is the net yield of ATP molecules produced directly via substrate-level and oxidative phosphorylation per molecule of glucose in aerobic respiration.
What is 30 to 32 ATP
This condition occurs when a single gene influences multiple, seemingly unrelated phenotypic traits.
What is pleiotropy
These specialized cells in the kidney's juxtaglomerular apparatus secrete renin in response to decreased blood pressure.
What are juxtaglomerular cells
This ecological interaction occurs when two species compete for the same limiting resource and one drives the other to local extinction.
What is the competitive exclusion principle
This enzyme unwinds the double helix during DNA replication by breaking hydrogen bonds.
What is DNA helicase
This law of thermodynamics states that the total entropy of an isolated system can never decrease over time.
What is the Second Law of Thermodynamics
This population-level phenomenon occurs when a sharp reduction in size due to environmental events or human activity leads to a loss of genetic diversity.
What is a population bottleneck
This primary pacemaker of the heart initiates the cardiac action potential.
What is the sinoatrial (SA) node
This type of survivorship curve, typical of large mammals and humans, features low mortality in early/middle life and high mortality in older age.
What is a Type I survivorship curve
This protein complex degrades unneeded or damaged proteins by proteolysis, tagging them with ubiquitin.
What is the proteasome
In the Calvin cycle of photosynthesis, this enzyme fixes carbon dioxide onto ribulose-1,5-bisphosphate (RuBP).
What is Rubisco (Ribulose-1,5-bisphosphate carboxylase-oxygenase)
In the Hardy-Weinberg equation (p² + 2pq + q² = 1), this term represents the frequency of the heterozygous genotype.
What is 2pq
This hormone, released by the posterior pituitary, regulates water reabsorption in the renal collecting ducts.
What is antidiuretic hormone (ADH or vasopressin)
This term describes an organism that exerts a disproportionate effect on its ecosystem relative to its abundance.
What is a keystone species
This organelle is responsible for O-linked glycosylation and sorting proteins for transport to lysosomes, the plasma membrane, or secretion.
What is the Golgi apparatus
This allosteric inhibitor of phosphofructokinase-1 (PFK-1) signals to the cell that energy supplies are already high.
What is ATP (or citrate)
This evolutionary mechanism describes the transfer of genetic material from one population to another via migration.
What is gene flow
During an action potential in a neuron, the rapid upstroke (depolarization) is caused by the influx of these ions.
What are sodium (Na⁺) ions
This biogeochemical cycle lacks a significant atmospheric phase and heavily relies on the weathering of rocks.
What is the phosphorus cycle
This small GTPase acts as a molecular switch, active when bound to GTP and inactive when bound to GDP, often mutated in human cancers like RAS.
What is Ras (or a G-protein)
This electron carrier has a lower standard reduction potential than NAD⁺ and operates primarily in anabolic pathways like the Calvin cycle and lipid synthesis.
What is NADPH
This phenomenon describes when two unrelated species independently evolve similar traits under similar selective pressuress.
What is convergent evolution
This neurohormone/neurotransmitter acts on the smooth muscle of blood vessels to cause vasoconstriction via alpha-1 adrenergic receptors during the "fight or flight" response.
What is norepinephrine (or epinephrine)
This ecological metric calculates species diversity by accounting for both species richness and the relative abundance of each species.
What is the Shannon-Wiener index (or Simpson's Diversity Index)