NAS 2 Challenge Exam – Questions With Verifiable
Solutions
Homeostasis Correct Answer - ability to maintain relatively stable
internal conditions even though the outside world changes continuously
Basic Mechanisms Correct Answer - receptor, control center, effector
Negative Feedback Mechanisms Correct Answer - most common
homeostasis control mechanism; the net effect is that the original output of
the system shuts off the original stimulus or reduces the intensity
Positive Feedback Mechanisms Correct Answer - cause the level of a
variable to change in the same direction as the an initial change
Levels of Organization: Correct Answer - chemical, cellular, tissue, organ,
organ system, organismal
Survival Needs Correct Answer - nutrients, oxygen, water, appropriate
temperature, atmospheric pressure
Requirements for Life Correct Answer - maintaining boundaries,
movement, responsiveness, digestion, metabolism, excretion, reproduction,
growth
Ionic bond Correct Answer - chemical bond between atoms formed by
the transfer of electrons
Covalent bond Correct Answer - shared electrons between atoms
Hydrogen bond Correct Answer - hydrogen shares a pair of electrons
with another atom
Nonpolar Correct Answer - electrically balanced molecules
Polar Correct Answer - non symmetrical molecules that contain
electrically unbalanced atoms (water)
Solutions
Homeostasis Correct Answer - ability to maintain relatively stable
internal conditions even though the outside world changes continuously
Basic Mechanisms Correct Answer - receptor, control center, effector
Negative Feedback Mechanisms Correct Answer - most common
homeostasis control mechanism; the net effect is that the original output of
the system shuts off the original stimulus or reduces the intensity
Positive Feedback Mechanisms Correct Answer - cause the level of a
variable to change in the same direction as the an initial change
Levels of Organization: Correct Answer - chemical, cellular, tissue, organ,
organ system, organismal
Survival Needs Correct Answer - nutrients, oxygen, water, appropriate
temperature, atmospheric pressure
Requirements for Life Correct Answer - maintaining boundaries,
movement, responsiveness, digestion, metabolism, excretion, reproduction,
growth
Ionic bond Correct Answer - chemical bond between atoms formed by
the transfer of electrons
Covalent bond Correct Answer - shared electrons between atoms
Hydrogen bond Correct Answer - hydrogen shares a pair of electrons
with another atom
Nonpolar Correct Answer - electrically balanced molecules
Polar Correct Answer - non symmetrical molecules that contain
electrically unbalanced atoms (water)
