Introduction: Themes in the Study of Life Flashcards
– the process of change that has transformed life here on Earth from its earliest beginnings to the diversity of organisms living today
– fundamental organizing principle of biology
evolution
– posing questions about the living world and seeking-based answers
– central activities of biology
scientific inquiry
some properties of Life
- order
- evolutionary adaptation
- response to the environment
- regulation
- energy processing
- growth and development
- reproduction
the overarching theme of biology; the idea that the organisms living on Earth today are the modified descendants of common ancestors
evolution
the reduction of complex systems to simpler components that are manageable to study
reductionism
Levels of Biological Organization
- Biosphere – includes most region of lands, most bodies of water, and the atmosphere to an altitude of several kilometers
- Ecosystems – consists of all living things in a particular area, along with all the nonliving components of the environment with which life interacts such as soil, water, atmospheric gases, and light
- Communities – entire array of organisms inhabiting a particular ecosystem
- Population – consists of all the individuals of a species living within the bounds of a specified area
- Organisms – individual living things
- Organs & organ system – organ: a body part consisting of two or more tissues & organ system: a team of organs that cooperate in a specific function
- Tissues – group of similar cells
- Cells – life’s fundamental unit of structure and function
- Organelle – various functional components that make up cells
- Molecules – a chemical structure consisting of two or more small chemical units called atoms
construct models for the dynamic behavior of whole biological system
system biology
The operation of any ecosystem involves two major processes:
1) Nutrient cycling
2) One-way flow of energy
Two main forms of cell
eukaryotic cell & prokaryotic cell
3 key research development to bring systems biology
- High throughput technology – tools that can analyze biological materials very rapidly and produce enormous amount of data
- Bioinformatics – which is the use of computational tools to store, organize, and analyze the huge volume of data that result from high-throughput methods
- Formation of interdisciplinary teams – melting pots of diverse specialists that may include computer scientists, mathematicians, engineers, chemists, physicists, and, of course, biologists from a variety of fields
is a regulatory motif common to life at all levels, from the molecular level to ecosystems and the biosphere
feedback
accumulation of end product of a process slows that process
negative feedback
in which an end product speeds up its production
positive feedback
one of the founders of modern evolutionary theory who quoted “Nothing in biology makes sense except in the light of evolution.”
Theodosius Dobzhansky
The Three Domains of Life
- Bacteria – are the most diverse and widespread prokaryotes and are now divided among multiple kingdoms.
- Archaea – live in Earth’s extreme environments, such as salty lakes and boiling hot springs.
- Eukarya
Protists
Fungi
Plantae
Animalia
On the Origin of Species by Means of Natural Selection
articulated two main points:
1) Darwin presented evidence to support his view that contemporary species arose from a succession of ancestors.
“descent with modification” – evolutionary history of species
2) Propose a mechanism for descent with modification
natural selection –mechanism of evolutionary adaptation where the natural environment “selects” for the propagation of certain traits.
Darwin’s observation from nature:
- Individuals in a population vary in their traits, many of which seem to be heritable (passed on from parents to offspring).
- A population can produce far more offspring than can survive to produce offspring of their own.
- With more individuals than the environment can support, competition is inevitable.
- Species generally suit their environments.
science
– is derived from a Latin verb meaning “to know”
– a way of knowing about the natural world. It developed out of our curiosity about ourselves, other lifeforms, our planet, and the universe.
the heart of science; a search for information and explanation, often focusing on specific questions.
inquiry
two main types of scientific inquiry:
discovery science
hypothesis-based science
mostly about describing nature
describes natural structures and processes as accurately as possible through careful observation and analysis of data
can lead to important conclusions based on a type of logic called induction, or inductive reasoning
discovery science
derive generalizations from a large number of specific observations
inductive reasoning
is the use of the senses to gather information, either directly or indirectly with the help of tools such as microscopes that extend our senses
observation
recorded observations; items of information on which scientific inquiry is based
data
data in the form of recorded descriptions rather than numerical measurements
qualitative data
data which are generally recorded as measurements
quantitative data
mostly about explaining nature
can lead to a deductive reasoning type of logic
- Hypothesis-based science
the logic flows in the opposite direction, from the general to the specific
deductive reasoning
– the proposing and testing of hypothetical explanations
– a tentative answer to a well-framed question—an explanation on trial
– usually an educated guess, based on experience and on the data available from discovery science
hypothesis
