Chemistry of Life
In plants, how might a decrease in transpiration rates due to high humidity levels impact the properties of water within xylem vessels?
There is less tension from transpirational pull, potentially reducing the cohesion between water molecules.
Capillary action becomes more efficient due to increased adhesion with vessel walls.
Transpirational pull increases, enhancing nutrient transport efficiency through mass flow.
Additional energy is required for root pressure to initiate upward movement against gravity.
Water must travel from the roots to the leaves of trees hundreds of feet tall. Which property of water is responsible for this?
High specific heat
Hydrogen bonding
Cohesion & adhesion
Universal solvency
Some insects can walk on water without breaking the surface. Which property of water is responsible for this?
Polarity
Universal solvency
High specific heat
High surface tension
What would be the most likely outcome on the properties of water if a mutation in a common aquatic plant led to the secretion of a compound that reduces hydrogen bonding among water molecules?
Decreased surface tension and potentially altered habitats for surface-dwelling organisms.
No significant change because other forces compensate for reduced hydrogen bonding.
Enhanced ice formation at warmer temperatures, affecting polar aquatic life.
Increased capacity of water to dissolve nonpolar substances, leading to changes in aquatic ecosystems.
How do water and solutes diffuse?
high to low concentration
water always leaves the cell
salt inside the cell always
low to high concentration
What is the probable outcome when a positive assortative mating occurs regularly within an isolated population?
Arrives at complete homogeneity without any differentiation in allele frequencies across individuals.
Positive assortative mating has no effect on genetic variation as it only involves movement of individual organisms without allele exchange.
Reduces genetic variability and believes increased vulnerability to environmental changes.
Increased homozygosity leading to more genetic similarities amongst individuals within the population.
What evolutionary mechanism can lead to adaptation where organisms become better suited for their environment due to differential survival?
Natural selection acts on phenotypic variation resulting from genetic differences among individuals.
Mutation introduces new genes into a population indiscriminately without regard for utility or fitness.
Gene flow moves alleles between populations but does not specifically enhance organismal fitness within an environment.
Genetic drift causes random changes in allele frequencies that may not necessarily result in adaptation.

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How could an enzyme that catalyzes reactions at low temperatures modify local intramolecular forces within liquid water below freezing point without acting as an antifreeze agent?
Enhancing stochastic molecular vibrations resulting in ephemeral non-covalent bonding disruptions.
Inducing transient realignments in adjacent molecule orientations without lowering freezing point.
Increasing localized dielectric constant manipulating solvent-solute interaction dynamics.
Inducing sporadic dipole flipping phenomena across multiple neighboring entities.
Which characteristic contributes most directly to the cohesive behavior observed between water molecules?
Surface tension created by nonpolar compounds.
Ionic interactions between dissolved mineral ions and H20 molecules.
The tendency for each molecule to form multiple hydrogen bonds.
A symmetrical linear shape allowing uniform charge distribution.
How does the structure of water contribute to its high specific heat capacity, which is critical for maintaining stable temperatures in aquatic environments?
The extensive hydrogen bonding network restricts molecular motion, requiring more energy to raise the temperature.
The linear shape of water molecules promotes tight packing, which reduces the amount of energy needed for heating.
The nonpolar regions of water create a buffer that absorbs heat and prevents temperature fluctuations.
The polar covalent bonds within water molecules easily break and reform, absorbing heat without increasing temperature.