Evolutionary thinkers + evidence
Features in different species that share structural similarities because they were inherited from a common ancestor are known as this.
What are homologous structures?
DNA replication occurs during this phase of the cell cycle, which occurs prior to both mitosis and meiosis.
What is Interphase (S phase)?
Mendel’s Law of Segregation states that two alleles for a heritable character separate during this biological process.
What is gamete formation (Meiosis)?
In the Hardy-Weinberg equation p2+2pq+q2=1, the expression 2pq represents the frequency of this genotype in a population.
What is the heterozygous genotype?
The Biological Species Concept defines a species based on the potential of individuals to do this in nature and produce viable, fertile offspring.
What is interbreed (or reproduce)?
List Darwin's four postulates required for natural selection to occur in a population.
(1) Variation exists among individuals, (2) Traits are heritable, (3) Survival and reproductive success are variable, and (4) Individuals with certain traits are more likely to survive and reproduce
While mitosis results in two genetically identical diploid daughter cells, meiosis produces this number and type of cells.
What are four genetically unique haploid cells (gametes)?
If a red flower and a white flower are crossed and produce 100% pink offspring, this inheritance pattern is occurring.
What is incomplete dominance?
Name the five conditions required for a population to remain in Hardy-Weinberg equilibrium (no evolution).
What are (1) No mutation, (2) Random mating, (3) No natural selection, (4) Extremely large population size (no genetic drift), and (5) No gene flow?
Similar biological traits that evolved independently due to convergent evolution, rather than shared ancestry, are known by this term
What is are analogous traits?
What is the difference between natural selection and evolution?
Natural Selection acts on individuals. Evolution is the change in populations over generations.
Homologous chromosomes separate during Meiosis I, whereas these separate during Meiosis II.
What are sister chromatids?
If a red flower and a white flower are crossed and produce 100% red and white offspring, this inheritance pattern is occurring.
What is codominance?
A random change in allele frequencies that has a significantly stronger impact on small populations than large ones is known as this.
What is genetic drift?
Rapid speciation events often follow these catastrophic global events because they open up many vacant ecological niches.
What are mass extinctions
What concept of Thomas Malthus’s idea on human population growth influenced Darwin's theory of evolution?
Populations grow exponentially, but resources are limited.
This cell division error occurs when chromosomes or chromatids fail to separate properly, leading to gametes with abnormal chromosome numbers.
What is nondisjunction?
A single gene influencing multiple, seemingly unrelated phenotypic traits is an example of this.
What is pleiotropy?
If you calculate the expected genotype frequencies for a population and they do not match the observed genotype frequencies, you can draw this conclusion about the population.
It is not in Hardy-Weinberg equilibrium
The fossil record exhibits bias because organisms with these physical characteristics are far more likely to be preserved over time.
What are hard parts (bones, shells, teeth)?
Unlike Darwin's natural selection, Jean-Baptiste Lamarck incorrectly proposed that evolution occurred through this mechanism.
What is the inheritance of acquired characteristics (use and disuse)?
These two key events during Meiosis I are responsible for generating unique genetic variation in gametes. Give phase as well.
What are crossing over (in Prophase I) and independent assortment (in Metaphase I)?
Genes located close together on the same chromosome that tend to be inherited together violate Mendel’s Law of Independent Assortment due to this phenomenon.
What is gene linkage?
Gene flow is the transfer of genetic material between populations through the movement of individuals which changes ___ ?
Allele frequencies
You are analyzing a pedigree tracking a genetic trait across three generations:
- Two unaffected parents have a child who is affected by the trait.
- The trait appears in both males and females in equal proportions.
Part A: Is this trait autosomal dominant or autosomal recessive?
Part B: What must be the exact genotypes of both unaffected parents?
Part A: Autosomal Recessive
Part B: Both parents must be heterozygous / carriers (Aa)