2026 COMPREHENSIVE QUESTIONS
SOLUTIONS GRADED A PLUS GENETICS AND
EVOLUTION STUDY PACKAGE
◉ gene flow-.
Answer: The result of fertile members of a species moving into or
out of a population.
◉ genetic diversity-.
Answer: Diversity in a population due to many different genetic
traits being present. A population with high amounts of allele variety
has high genetic diversity.
◉ genetic drift-.
Answer: The change in a gene pool as a result of random chance.
◉ Glucose-.
Answer: A simple carbohydrate (monosaccharide) with the chemical
formula of C6H12O6. This is the primary product (output) of
photosynthesis and the primary reactant (input) of cellular
respiration.
,◉ Glycolysis-.
Answer: The breakdown of glucose into pyruvate. Occurs in the
cytoplasm of cells and produces small amounts of the energy
molecule ATP and the electron carrier molecule NADH.
◉ Haploid-.
Answer: Cells that contain only one set of chromosomes. Haploid
cells are referred to as "1n." Gametes (sperm and eggs) are haploid.
In human haploid gametes contain 23 chromosomes.
◉ Histones-.
Answer: Small proteins found along the length of chromosomes that
can move closer or farther apart to help chromosomes contract into
chromatin during cell division or decondense after cell division is
complete.
◉ homologous chromosomes-.
Answer: Chromosome pairs (one from each parent) that are similar
in length, gene position, and centromere location. The position of the
genes on each homologous chromosome is the same, however, the
genes may contain different alleles.
◉ hydrogen bonds-.
Answer: Hydrogen bond (H-bond) is an interaction between a
partially positive hydrogen atom and a partially negative atom with
,an unshared (lone) pair of electrons. In order for hydrogen to have a
sufficient partial positive charge, hydrogen must be covalently
attached to a very electronegative atom (O, N, P). A partially negative
atom with a lone pair of electrons must also be a highly
electronegative atom like oxygen or nitrogen.
◉ hydrophilic. -.
Answer: Substances that dissolve in, or are attracted to, water.
Hydrophilic (from Greek meaning "water-loving") refers to
molecules that are water soluble. Hydrophilic molecules contain
polar functional groups that can form hydrogen bonds or ionic
bonds with water. Ionic and polar substances are hydrophilic.
◉ hydrophobic.-.
Answer: Hydrophobic (from Greek meaning "water-fearing") refers
to molecules that do not interact with water and are characterized
by a complete lack of electronegative atoms. In aqueous solutions,
the hydrophobic molecules are driven together to the exclusion of
water.
◉ incomplete dominance-.
Answer: A form of intermediate inheritance where one allele for a
specific trait is not completely expressed over the other allele in the
heterozygote. This results in a third phenotype where the expressed
physical trait is a combination of the phenotypes of both alleles.
, ◉ inorganic molecules-.
Answer: Simple molecules not found in living things. They may
contain carbon or hydrogen, but not both. Examples include CO2,
N2, O2.
◉ Interphase-.
Answer: The stage of the cell cycle when division (mitosis) does not
occur. During interphase, the cell grows, acquires nutrients, and
replicates both its chromosomes as well as its organelles. Interphase
consists of the G1 (chromosomes condense), S (DNA duplicates), and
G2 (DNA integrity checked and repaired) phases of the cell cycle.
Cells spend the majority of their time in interphase.
◉ interspecific interaction-.
Answer: An effect of one population on another in a community; any
interaction between members of different species. This is a type of
community interaction and has three subtypes: mutualism,
predation, and competition.
◉ ionic bonds-.
Answer: An attractive force generated by the interactions between
ions of opposite charges. An ionic bond forms due to an attraction
between a positive and a negative ion. No electron sharing occurs in
the ionic bond. In the formation of an ionic bond, electrons are said
to be transferred from one atom to another.