NLN NEX PRACTICE EXAM QUESTIONS AND
DETAILED SOLUTIONS 2026
▶ Vacuole. Answer: a membrane-bound sac within a cell that acts like a
storage unit, holding water, nutrients, or waste
▶ Chromatin. Answer: Clusters of DNA, RNA, and proteins in the nucleus
of a cell. The material of which the chromosomes of organisms other than
bacteria (i.e., eukaryotes) are composed. It consists of protein, RNA, and
DNA.
▶ Chromosomes. Answer: a threadlike structure of nucleic acids and
protein found in the nucleus of most living cells, carrying genetic
information in the form of genes.
▶ mitosis. Answer: a type of eukaryotic cell division that results in two
daughter cells each having the same number and kind of chromosomes as
the parent nucleus, typical of ordinary tissue growth.
▶ zygote. Answer: a diploid cell resulting from the fusion of two haploid
gametes; a fertilized ovum. the first single cell formed when a sperm
fertilizes an egg, containing all the genetic material (DNA) from both
parents to develop into a new organism.
▶ meiosis. Answer: a special cell division process that creates four
genetically unique sex cells (sperm or eggs) from one parent cell, each with
half the number of chromosomes.
▶ semipremeable membrane. Answer: A membrane that allows some
molecules to pass through but does not allow other molecules to pass
through.
▶ ATP. Answer: (adenosine triphosphate) main energy source that cells
use for most of their work
, ▶ Organ. Answer: Performs a specialized function in the body.
▶ Organ System. Answer: made up of a number of organs working
together to carry out a major function.
▶ Organism. Answer: The highest level of organization, such as the
human body.
▶ Active transport. Answer: involves the use of energy in the form of ATP
to move substances across the membrane.
▶ Passive Transport. Answer: does not require energy and uses diffusion
and filtration.
▶ Facilitated diffusion.. Answer: Form of passive transport that involves
the use of membrane proteins.
▶ Diffusion. Answer: Particles move randomly, spreading evenly
throughout an available space and moving from regions of high to low
concentrations
▶ Osmosis. Answer: Water moves from an area of high-water
concentration to an area of low-water concentration
▶ Isotonic. Answer: When the solute concentration of the water is the
same as that inside the cell. The amount of water that leaves the cell and
the amount that enters it are equal
▶ Hypertonic. Answer: When the solute is more concentrated outside the
cell than inside it. The cell shrinks.
▶ Hypotonic. Answer: The solute concentration is less concentrated
outside the cell than inside it. The cell expands.
▶ Filtration. Answer: The movement of water and solutes through the
membrane by fluids or hydrostatic pressure.
▶ Natural Selection. Answer: Variations that give individuals an advantage
in the struggle for survival
DETAILED SOLUTIONS 2026
▶ Vacuole. Answer: a membrane-bound sac within a cell that acts like a
storage unit, holding water, nutrients, or waste
▶ Chromatin. Answer: Clusters of DNA, RNA, and proteins in the nucleus
of a cell. The material of which the chromosomes of organisms other than
bacteria (i.e., eukaryotes) are composed. It consists of protein, RNA, and
DNA.
▶ Chromosomes. Answer: a threadlike structure of nucleic acids and
protein found in the nucleus of most living cells, carrying genetic
information in the form of genes.
▶ mitosis. Answer: a type of eukaryotic cell division that results in two
daughter cells each having the same number and kind of chromosomes as
the parent nucleus, typical of ordinary tissue growth.
▶ zygote. Answer: a diploid cell resulting from the fusion of two haploid
gametes; a fertilized ovum. the first single cell formed when a sperm
fertilizes an egg, containing all the genetic material (DNA) from both
parents to develop into a new organism.
▶ meiosis. Answer: a special cell division process that creates four
genetically unique sex cells (sperm or eggs) from one parent cell, each with
half the number of chromosomes.
▶ semipremeable membrane. Answer: A membrane that allows some
molecules to pass through but does not allow other molecules to pass
through.
▶ ATP. Answer: (adenosine triphosphate) main energy source that cells
use for most of their work
, ▶ Organ. Answer: Performs a specialized function in the body.
▶ Organ System. Answer: made up of a number of organs working
together to carry out a major function.
▶ Organism. Answer: The highest level of organization, such as the
human body.
▶ Active transport. Answer: involves the use of energy in the form of ATP
to move substances across the membrane.
▶ Passive Transport. Answer: does not require energy and uses diffusion
and filtration.
▶ Facilitated diffusion.. Answer: Form of passive transport that involves
the use of membrane proteins.
▶ Diffusion. Answer: Particles move randomly, spreading evenly
throughout an available space and moving from regions of high to low
concentrations
▶ Osmosis. Answer: Water moves from an area of high-water
concentration to an area of low-water concentration
▶ Isotonic. Answer: When the solute concentration of the water is the
same as that inside the cell. The amount of water that leaves the cell and
the amount that enters it are equal
▶ Hypertonic. Answer: When the solute is more concentrated outside the
cell than inside it. The cell shrinks.
▶ Hypotonic. Answer: The solute concentration is less concentrated
outside the cell than inside it. The cell expands.
▶ Filtration. Answer: The movement of water and solutes through the
membrane by fluids or hydrostatic pressure.
▶ Natural Selection. Answer: Variations that give individuals an advantage
in the struggle for survival
