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60 terms

Biology Midterm

Honors Biology Midterm Exam. Not too much on biogeochemical cycles
STUDY
PLAY
population
a group of individuals belonging to one species and living in the same geographic area
natural selection
a process in which organisms with certain inherited characteristics are more likely to survive and reproduce than organisms with other characteristics
theory of evolution
the change over time of populations into different forms from a common ancestor
common ancestor
the shared ancestor of new, different species
adaptation
an inherited characteristic that enhances us organism's ability to survive and reproduce in a particular environment
extinction
the irrevocable loss of species
ecology
the scientific study of how organisms interact with their environments
abiotic factor
a nonliving component of an ecosystem such as water, air or temperature
biotic factor
a living component of an environment
ecosystem
all the organisms in a given area, along with the nonliving factors with which they interact; a biological community and physical environment
niche
the status of an organism within its environment and community
symbiosis
a close association between organisms of two or more species
competition
the struggle between organisms to survive in a habitat with limited resources
mutualism
an interspecific relationship in which both partners benefit
predation
an interaction between two species in which one species, the predator, eats the other, the pray
herbivory
consumption of plant parts or algae by an animal
parasitism
the relation between two different kinds of organisms in which one receives benefits from the other by causing damage to it
autotroph
an organism that makes its own food by photosynthesis, thereby sustaining itself without eating other organisms
photosynthesis
the process by which plants, autotrophic protists, and some bacteria use light energy to make sugars and other organic food molecules from carbon dioxide and water
heterotroph
an organism that cannot make its own food and must obtain them from consuming organisms or their organic products
herbivore
organism that obtains energy by eating only plants
carnivore
organism that obtains energy by eating animals
omnivore
organism that obtains energy by eating both plants and animals
food chain
a sequence of food transfers from producers through one to four levels of consumers in an ecosystem
food web
a network of interconnecting food chains
10% rule
only 10% of energy in each organism is taken in by the predator when eaten; other 90% is lost
respiration
carbon in the form of carbon dioxide gas being emitted by living organisms on the planet when they make energy
combustion
burning of gas, wood, oil, etc. by humans to make electrical energy which emits large quantities of CO2 into the atmosphere
erosion
weather such as rain erodes phosphorus from rocks to be used by plants
proton
a subatomic particle with a single positive electrical charge; found in the nucleus of an atom
electron
a subatomic particle with a single negative electrical charge; one or more electrons move around the nucleus of an atom
valence shell
The outermost energy shell of an atom, containing the valence electrons
shells
the orbits of electrons around the nucleus
molecule
a group of two or more atoms held together by covalent bonds
ion
an atom that has gained or lost one or more electrons, thus acquiring a charge
covalent bond
an attraction between atoms that share one or more pairs of outer-shell electrons (valence electrons)
hydrophobic
"water-fearing"
hydrophilic
"water-loving"
hydrogen bond
a weak chemical bond formed when the partially positive hydrogen atom is attracted to the partially negative atom
cohesion
the binding together of like molecules, often by hydrogen bonds
adhesion
the attraction between different kinds of molecules
surface tension
a measure of how difficult it is to stretch or break the surface of a liquid; water has a high surface tension because the hydrogen bonding of surface molecules
pH scale
a measure of the relative acidity of a solution, ranging in value from 0 (most acidic) to 14 (most basic); pH = potential hydrogen, refers to the concentration of hydrogen ions
prokaryotic cell
a type of cell lacking a membrane-enclosed nucleus and other membrane-enclosed organelles; found only in bacteria and archaea
eukaryotic cell
a type of cell that has a membrane-enclosed nucleus and other membrane-enclosed organelles; all organisms except bacteria and archaea have these
organelle
a membrane-enclosed cell structure with a specialized function within a cell
cytoplasm
everything inside a cell between the plasma membrane and the nucleus; consists of a semifluid medium and organelles
cell wall
a protective layer external to the plasma membrane in plant cells, bacteria, fungi, and some protists; protects cell and helps maintain its shape
chloroplast
an organelle found in plants and photosynthesis protists that absorbs sunlight and uses it to drive the synthesis of organic molecules from carbon dioxide
nucleus
1) an atom's central core, containing protons and neutrons 2) the genetic control center of a eukaryotic cell
diffusion
the spontaneous tendency of a substance to move down its concentration gradient from where it is more concentrated to where it is less concentrated
osmosis
the diffusion of water across a selective permeable barrier
hypertonic solution
in comparing two solutions, the one with the greater concentration of solutes; cells in such a solution will lose water to their surroundings
hypotonic solution
in comparing two solutions, the one with the lower concentration of solutes; cells in such a solution will take up water from their surroundings
isotonic solution
a solution having the same solute concentration as another solution, thus having no effect on passage of water in or out of the cell
photosynthesis equation
6CO2 + 6H2O → C6H12O6 + 6O2
cellular respiration equation
C6H12O6 + 6O2 → 6CO2 + 6H2O
oxidization
the loss of electrons from a substance involved in a redox reaction
carbohydrate
molecules consisting of simple single-monomer sugars (monosaccharides), two-monomer sugars (disaccharides), and other multiunit sugars (polysaccharides)
dehydration reaction
a chemical process in which two molecules become covalently bonded to each other with the removal of a water molecule