Macromolecules & Water
Molecules that form hydrogen bonds with water are called ___.
Polar
Basic unit of life.
Cell
Biological catalysts are called ___.
Enzymes
Physical expression of a trait.
Phenotype
Process where organisms with favorable traits survive and reproduce.
Natural selection
What reaction builds polymers by removing water?
Dehydration synthesis
Organelle that packages and ships proteins.
Golgi apparatus
Molecule that stores and transfers energy.
ATP
Process that makes RNA from DNA.
Transcription
Random change in allele frequencies in small populations.
Genetic drift
What property of water allows insects to walk on its surface?
Surface tension (cohesion)
What model describes the membrane’s structure?
Fluid mosaic model
What happens to an enzyme at very high temperature?
Denaturation
When homologous chromosomes exchange DNA segments.
Crossing over
Maximum population size environment can support.
Carrying capacity
Why does ice float on liquid water?
Hydrogen bonds make ice less dense
Why do small cells have higher SA:V ratios?
More membrane area per volume → faster diffusion
Where does the electron transport chain occur?
Inner mitochondrial membrane
What phase of mitosis separates sister chromatids?
Anaphase
What type of selection favors intermediate phenotypes?
Stabilizing selection
Explain how hydrogen bonding contributes to water’s high specific heat and biological stability.
Bonds absorb heat energy before breaking, moderating temperature change
Predict how a cell would respond if placed in a hypertonic solution.
Water leaves → cell shrinks
Explain how chemiosmosis produces ATP in both respiration and photosynthesis.
H⁺ gradient drives ATP synthase phosphorylation
Explain how meiosis increases genetic variation.
Independent assortment and crossing over create new allele combinations
Explain how energy transfer limits trophic levels in ecosystems.
Only ≈ 10% energy passes to next level → few top predators