Lesson 1.1: What is Biology Flashcards
organisms
an individual living entity that grows and reproduces as an independent unit
nucleic acids
a polymer made up of nucleotides, specialized for the storage, transmission, and expression of genetic information
ex: DNA and RNA
cell
the simplest structural unit of a living organism
- in multicellular organisms, many individual cells serve as the building blocks of tissue and organs
prokaryotes
unicellular organisms that do NOT have nuclei
(contrast with eukaryotes)
photosynthesis
metabolic processes carried out by green plants and cyanobacteria, by which visible light is trapped and the energy used to convert CO2 into organic compounds
aerobic metabolism
in the presence of O2; requiring or using oxygen
- a set of chemical reactions that releases energy from life’s molecules by using O2
anaerobic metabolism
occurring without the use of molecular O2
- a set of reactions that extract energy without using O2
organelles
any of the membrane-enclosed structures within a eukaryotic cell
ex: nucleus, endoplasmic reticulum, mitochondria
nucleus
centrally located compartment of eukaryotic cells that is enclosed by a double membrane and contains the chromosomes (cell’s genetic information)
eukaryotes
organisms made up of one or more complex cells in which the genetic material is contained in nuclei
endosymbiosis
the engulfing of one cell by another
- “living inside another”
mitochondria
organelle in eukaryotic cells that contains the enzymes of the citric acid cycle, respiratory chain, and oxidative phosphorylation
- release energy for use
chloroplasts
organelle bound by a double membrane containing the enzymes and pigments that perform photosynthesis
- occur only in eukaryotes
cellular specialization
in multicellular organisms, the division of labor such that different cell types become responsible for different functions
genome
complete DNA (sometimes RNA) sequence for a particular organism or individual
- sum total of an organism’s genetic material
mutations
a change in the genetic material that is not caused by recombination
binomial
a taxonomic naming system in which each species is given two names (genus species)
- italicized
phylogenetic trees
a graphic representation of the lines of descent among organisms or their genes
tree of life
term that encompasses the evolutionary history of all life, or a graphic representation of that history
bacteria
unicellular organisms lacking a nucleus
- one of the two primary divisions of life
archaea
unicellular organisms that lack a nucleus and lack a peptidoglycan in the cell wall
- one of the two primary branches of life
domains
the tree monophyletic branches of life:
1) bacteria
2) archaea
3) eukarya
model systems
small group of species that are the subject of extensive research
- adapt well to lab situations
tissues
a group of similar cells organized into a functional unit
organ
a body part, composed of two or more tissues integrated to perform a distinct function
organ systems
an interrelated and integrated group of tissues and organs that work together in a physiological function
ecological systems
one or more organisms and the environment they interact with
- ecosystems
populations
group of individuals of the same species that live, interact, and reproduce together in a particular geographic area
communities
the assemblage of interacting individuals of different species within a particular geographic area
landscapes
ecological system consisting of multiple ecological communities within a geographic area larger than the area occupied by a single community
- biosphere is landscape of entire earth and all its life
system
set of interacting parts in which neither the parts nor the whole can be understood without taking into account their interaction with each other
components
interacting parts of a biological system
processes
ways in which biological components interact
feedback
in regulatory systems, information about the relationship between the set point of the system and its current state
- positive: when a product of the system speeds up an earlier process
- negative: when a product of a system slows down an earlier process
regulatory systems
system that uses feedback information to maintain a physiological function or parameter at an optimal level
systems analysis
process in which parts/components of a biological system are identified and the process by which they interact are specified
equilibrium
state of a system in which there is no net change throughout time
- state of stable balance
nucelotide
building blocks of nucleic acids and important coenzymes
DNA
deoxyribonucleic acid; fundamental hereditary material of all living organisms
proteins
compound consisting of one, or more polypeptides
- molecules that govern chemical reactions within cells and form much of organism’s structure
gene
unit of heredity; unit of genetic function which carries the information for a polypeptide
evolution
change in the genetic makeup of biological populations through time
natural selection
the differential contribution of offspring to the next generation by various genetic types belonging to the same population
- mechanism of evolution proposed by Charles Darwin
adaptations
structural, physiological, or behavioral traits that increase an organism’s chances of surviving and reproducing in its specific environment
proximate explanations
immediate genetic, physiological, neurological, and developmental explanations for the advantages of an adaptation
ultimate explanation
historical explanations of the processes that led to the evolution of an adaptation
genetic drift
random changes in gene frequencies in a population because of chance events
theory
a body of scientific work in which rigorously tested and well-established facts and principles are used to make predictions about the natural world
