Bio 180 (Midterm 1) questions and answers 2026\2027
A+ Grade
Natural Selection
- correct answer natural selection occurs when individuals with certain heritable traits produce more
surviving offspring than do individuals without those traits.
Natural selection is the process through which species adapt to their environments. It is the engine that
drives evolution.
differential survival and reproduction of individuals due to differences in phenotype. It is a key
mechanism of evolution, the change in the heritable traits characteristic of a population over
generations.
Fitness
- correct answer What does fitness mean in biology?
s the ability of an individual to produce surviving, fertile offspring relative to that ability in other
individuals in the population.
How is fitness measured in evolution?
Fitness evolution is when a species biological fitness can change from one generation to another.
- Fitness evolution can be altered due to a change in the genotype of a species or a change in
environment.
adaptation
- correct answer a heritable trait that increases the fitness of an individual in a particular environment
relative to individuals lacking the trait.
competition
- correct answer a biological interaction between or among the same or different organisms where the
organisms fight for resources (survive in a habitat w limited resources, often food)
, selection
- correct answer passive process-differential reproduction as a result of heritable variation-not a
purposeful choice.
Selection pressures are external agents which affect an organism's ability to survive in a given
environment
Selection pressures can be negative (decreases the occurrence of a trait) or positive (increases the
proportion of a trait)
Selection pressures may not remain constant, leading to changes in what constitutes a beneficial
adaptation
artificial selection
- correct answer Breeding organisms with specific traits in order to produce offspring with identical
traits.
choosing certain individuals with desirable traits to reproduce, thus manipulating the composition of 1e
population
heritable traits
- correct answer A trait that can be passed on genetically from parent to offspring.
population thinking
- correct answer variation among individuals in a population was the key to understanding the nature of
species
polygenic
- correct answer trait controlled by two or more genes
genes each one exerting a relatively small effect-influence the trait
trait
- correct answer A characteristic that an organism can pass on to its offspring through its genes.
A+ Grade
Natural Selection
- correct answer natural selection occurs when individuals with certain heritable traits produce more
surviving offspring than do individuals without those traits.
Natural selection is the process through which species adapt to their environments. It is the engine that
drives evolution.
differential survival and reproduction of individuals due to differences in phenotype. It is a key
mechanism of evolution, the change in the heritable traits characteristic of a population over
generations.
Fitness
- correct answer What does fitness mean in biology?
s the ability of an individual to produce surviving, fertile offspring relative to that ability in other
individuals in the population.
How is fitness measured in evolution?
Fitness evolution is when a species biological fitness can change from one generation to another.
- Fitness evolution can be altered due to a change in the genotype of a species or a change in
environment.
adaptation
- correct answer a heritable trait that increases the fitness of an individual in a particular environment
relative to individuals lacking the trait.
competition
- correct answer a biological interaction between or among the same or different organisms where the
organisms fight for resources (survive in a habitat w limited resources, often food)
, selection
- correct answer passive process-differential reproduction as a result of heritable variation-not a
purposeful choice.
Selection pressures are external agents which affect an organism's ability to survive in a given
environment
Selection pressures can be negative (decreases the occurrence of a trait) or positive (increases the
proportion of a trait)
Selection pressures may not remain constant, leading to changes in what constitutes a beneficial
adaptation
artificial selection
- correct answer Breeding organisms with specific traits in order to produce offspring with identical
traits.
choosing certain individuals with desirable traits to reproduce, thus manipulating the composition of 1e
population
heritable traits
- correct answer A trait that can be passed on genetically from parent to offspring.
population thinking
- correct answer variation among individuals in a population was the key to understanding the nature of
species
polygenic
- correct answer trait controlled by two or more genes
genes each one exerting a relatively small effect-influence the trait
trait
- correct answer A characteristic that an organism can pass on to its offspring through its genes.
