RESPIRATION, CIRCULATION, AND EXCRETION
SUMMARY 2026
◉ convergent evolution.
Answer: Process by which unrelated organisms independently
evolve similarities when adapting to similar environments
◉ Adaptive radiation.
Answer: -An evolutionary pattern in which many species evolve
from a single ancestral species
-evolution from a common ancestor of many species adapted to
diverse environments
*Rapid phenotypic adaptation of species to a range of environments
resulting in morphological and physiological adaptations
◉ What is adaptive radiation based on?.
Answer: 1. Morphology (morphing)
2. Niche
3. Geography
◉ Why are there different alleles of a gene?.
,Answer: mutation
◉ How did the bacteria get this resistant allele? (Natural Selection).
Answer: Inherited it
◉ Natural Selection.
Answer: Affects the fitness of a single individual in a population
depending on their traits
◉ Evolution - in reference to frequencies.
Answer: Differing fitness causes frequencies of genes in the
populations to change
◉ The target of natural selection is....
Answer: individual
◉ Precondition 1 of Natural Selection.
Answer: Heritable variation
1. Functional characteristics
2. Physical characteristics
3. Behavioral characteristics
, ◉ What is the source of heritable variation?.
Answer: Mutations leading to new alleles
◉ Contributions of Meiosis.
Answer: 1. Crossing over between homologous chromosomes
2. Independent assortment of homologous chromosomes
3. Fertilization - bringing genes from 2 parents together
◉ Precondition 2 for Natural Selection.
Answer: organisms struggle to survive (Competition?)
◉ Precondition 3 for Natural Selection.
Answer: organisms differ in fitness
◉ Fitness.
Answer: the relative reproductive success of an individual
◉ Adaptation.
Answer: -A trait that helps an organism survive and reproduce
-Any heritable trait that increases the fitness of an individual in a
particular environment relative to individuals lacking the trait