Gen Zoo Chap 3 Flashcards
Body of thoroughly tested and verified explanations for a set of observations of the natural world
Theory
Best explanation of observed phenomena
Theory
Change over a period of time
Evolution
Darwinism and Evolution though Natural Selection
Charles Darwin
Evolution
- Charles Darwin
- Alfred Russel Wallace
The living world is neither constant nor perpetually cycling. It is always changing
Perpetual Change
All forms of life descended from a common ancestor through a branching of lineages
Common Descent
Evolutionary process new species by splitting and transforming older ones
Multiplication of Species
Large difference in anatomical traits that characterize different species originate through
the accumulation of many small changes in the genes over very long periods of time
Gradualism
Organisms constructed to meet the demands of their environment
Natural Selection
must makes lot of offspring to
maintain population; not all survive adulthood
Overproduction
Natural resources are limited;
struggle for existence
Competition
Adapt better tend to survive
Selection
Most favorable traits leads to
production of new species overtime
Adaptation
similar structures shared
between different animals with common ancestry
Homologous Structure
Structures between
different animals look and function the same but evolved separately (no common ancestry)
Analogous Structure
Structures from past ancestor that may have lose all or most of its original function in the course of evolution as it is no longer needed
Vestigial
Relatedness of groups or organisms is reflected
to DNA sequences
DNA Comparisons
study of species distribution
Biogeography
Physical characteristics increases organisms
finding mate
Sexual Selection
- Formation of new species
- Start to develop new traits
- DNA drift apart
Speciation
Process by which an organism becomes better suited to
its environment through changes in its traits or
behaviors
Adaptation
Types of Adaptation
1.) Structural (Physical features)
2.) Behavioral (ways of acting)
3.) Physiological (internal functions)
Introduction of new variation
Mutation
Continues exchange of genes between 2 or more populations of the same species
Gene Flow
Transfer genetic material between population
through migration
Gene Flow
Random changes of allele frequencies especially
in small population due to chance events
Genetic Drif
Differential survival and reproduction of individual with certain traits, leading to changes in allele frequencies over time
Natural Selection
Small-scale evolutionary changes that could lead to appearance of new variants within a species
Microevolution
Large-scale evolutionary changes that take place
after a long period of time
Macroevolution
The union of male (sperm) and female (egg) gametes to form a zygote, initiating development.
Fertilization
Rapid mitotic cell divisions of the zygote without growth, resulting in a multicellular structure called a blastula.
Cleavage
The process by which the blastula reorganizes into a three-layered structure called the gastrula, forming the primary germ layers: ectoderm, mesoderm, and endoderm.
Gastrulation
The formation and differentiation of organs and tissues from the germ layers. This stage involves the development of the nervous system, muscles, bones, and other organs.
Organogenesis
The increase in size and the shaping of the organism’s body and organs, guided by genetic and environmental factors.
Growth and Morphogenesis
The final stage of development where the organism reaches sexual maturity and is capable of reproduction.
Maturation
A dramatic transformation from a larval stage to an adult form, as seen in insects (e.g., caterpillar to butterfly) and amphibians (e.g., tadpole to frog).
Metamorphosis
