Biology Concepts and Investigations: Chapter 1
organism
a single living individual
organ
a structure consisting of tissues organized to interact and carry out specific functions (multicellular life only)
scientific method
a systematic approach to understanding the natural world based on evidence and testable hypothesis
experiment
a test of a hypothesis under controlled conditions
hypothesis
a testable, tentative explanation based on prior knowledge
community
all populations that occupy the same region
variable
any changeable element in an experiment
standardized variable
any factor held constant for all subjects in an experiment
reproduction, growth, & development (life)
reproduces and makes individuals similar to themselves; grow and develop over time
dependent variable
response that may be under the influence of an independent variable
predictions
say a specified thing will happen in the future
cell
the fundamental unit of life
biosphere
the global ecosystem; the parts of the planet and its atmosphere where life is possible
statistically significant
unlikely to be attributed to chance
control
untreated group used as a basis for comparison with a treated group in an experiment
theory
well-supported scientific explanation
evolution (life)
not into completely new creatures, but adapted versions of itself
sample size
number of subjects in each experimental group
Give examples of questions that you cannot answer using the scientific method.
-values -beauty -morals -honor -freedom -love -purpose
steps of scientific method
1. Observations and questions 2. Hypothesis and prediction 3. Data collection 4. Analysis and peer review
five characteristics of life
1. Organization 2. Energy use 3. Maintenance of internal constancy 4. Reproduction, growth, & development 5. Evolution
Why is a cell, and not an atom or a molecule, considered the basic unit of life?
A cell is the basic unit of life because it is applicable to the five characteristics of life, while atoms and molecules are not.
How does a home's air conditioning system illustrate homeostasis?
Whether the air conditioning or heat is on, a house will maintain its set temperature.
tissue
a collection of specialized cells that function in a coordinated fashion (multicellular life only)
species
a distinct type of organism
molecules
a group of joined atoms
population
a group of the same species of organism living in the same place and time
organelle
a membrane-bounded structure that has a specific function within a cell
domain
broadest (most inclusive) taxonomic category
evolution
descent with modification; change in allele frequencies in a population over time
natural selection
differential reproduction of organisms based on inherited traits
peer review
evaluation of scientific results by experts before publication in a journal
asexual reproduction
form of reproduction in which offspring arise from only one parent
independent variable
hypothesized influence on a dependent variable
placebo
inert substance used as an experimental control
adaptation
inherited trait that permits an organism to survive and reproduce
decomposers
organisms that consume wastes and dead organic matter, returning inorganic nutrients to the ecosystem
producers (autotrophs)
organisms that use inorganic sources of energy and carbon
consumers (heterotrophs)
organisms that use organic sources of energy and carbon
organ system
organs connected physically or chemically that function together (multicellular life only)
organization (life)
parts organize to make a functioning pattern
technology
practical application of scientific knowledge
emergent property
quality that results from interactions of a system's components
energy use (life)
reactions called metabolism allow organs to acquire and use energy
kingdoms
taxonomic category below domain
genus
taxonomic category that groups closely related species
homeostasis
the ability of an organism to maintain a stable internal environment despite changes in the external environment
sexual reproduction
the combination of genetic material from two individuals to create a third individual
maintenance of internal constancy (life)
the conditions inside the cells have to stay in a constant range
ecosystem
the living and nonliving components of an area
taxonomy
the science of describing, naming, and classifying organisms
atoms
the smallest chemical unit of a type of pure substance (element)