Lecture 2 - Evolution and the domains of life Flashcards
What is taxonomy
Taxonomy: the way to classify groups
in biological systems
what are examples of morphological
characteristics?
colour, pattern,
bones, organs
What is the hierarchy of biological classification?
Domain kingdom phylum class order family genus species
What does evolution lead to?
both variation and unity
explain homologous structures
Although forelimbs look very different on the outside, there remain similarities in their skeletal structure • Shared a common ancestor, and different environmental condition led to the individual evolutionary changes of each species • After millions of years, still retain core
what were the first steps towards developing the theory of evolution?
aristotle - developed scala naturae “‘ladder of ife”, based on organisms function and complexity
Carl linnaeus - developed hierarchies based on morphological characteristics
-pioneered binomial nomenclature
which theory of evolution did Aristotle and Linnaeus believe?
the doctrine of fixed species
What did Jean baptiste lamarck develop? explain
the theory of lamarckian evolution.
- thought organisms traits could change throughout their lifetime through use and disuse
- thought these could easily be passes onto their offspring
- giraffes example
what is good and bad about the lamarckian theory?
organisms traits can change throughout their lifetime, BUT it is very difficult to pass these traits onto their offspring.
what did charles darwin develop?
he refuted the doctrine of fixed species
developed the theory of evolution by natural selection
what aspects of evolution show unity?
homologous structures
for example
what aspects show diversity?
- after an environmental change, physical traits may give a survival advantage
- example: antibiotic resistant gene in bacteria
- organisms in that environment are going to be selected for, but not necessarily in other environments without the selective condition
what is the central dogma of evolution?
environmental change –> selective pressure overtime –> new species
what determines physical traits?
- DNA contains genes, which encode proteins
- expression and activity of the proteins determine the structure and function of cells
- cells are the basic unit of life for all organisms
- cells can inherit or obtain DNA from other cells in a number of ways.
how can cells inherit or obtain DNA from other cells?
conjunction/transduction
mitosis
meiosis
asexual + sexual reproduction