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the study of plants


the study of animals


the study of insects


the study of body structure


the study of heredity


the study of interaction of living things and their environment


the study of structures and functions of cells


the study of fossil animals and plants

Robert Hooke

a English scientist who was the first person to see cells from thin slices of cork using a three-lens compound microscope

Anton van Leeuwenhoek

a Dutch tradesman who was one of the first people to describe living cell and drew animalcules using a single-lens microscopes

Scanning Electron Microscope

a microscope that scans the surface of a specimen with a beam of electrons and the specimen's surface is usually coated with a very thin layer of a metal that deflects the electrons

Transmission Electron Microscope

a microscope that transmits electrons through a thin slice of a specimen, it makes a two-dimensional image similar to that of a light microscope, but with a much higher magnification

cell theory

-all organisms are made of cells
-all existing cells are produced by other living cells
-the cell is the most basic unit of life

Matthias Schleiden

a German scientist that was first to note that plants are made of cells

Theodor Schwann

a German scientist that concluded that all living things are made of cells

Rudolf Virchow

a German scientist that proposed that all cells come from other cells

prokaryotic cells

cell that don't have a nucleus or other membrane-bound organelles

eukaryotic cells

cells that have a nucleus and other membrane-bound organelles


a network of proteins that is constantly changing to meet the needs of a cell


long hollow tubes that give the cell its shape and act as "tracks" for the movement of organelles


fills the space between the nucleus and the cell membrane in eukaryotes


the fluid portion, excluding the organelles, of the cytoplasm and consists mostly of water


the storehouse for most of the genetic information, or DNA

nuclear envelope

the cell's DNA enclosed in a double membrane


holes in the nuclear envelope that allow molecules to pass between the nucleus and cytoplasm


a dense region in the nucleus where tiny organelles essential for making proteins are assembled


a combination of proteins and RNA molecules that link amino acids together to form proteins

endoplasmic reticulum

an interconnected network of thin folded membranes that produce proteins and lipids

rough endoplasmic reticulum

an endoplasmic reticulum that produce modified proteins with sugar chains added to it

smooth endoplasmic reticulum

an endoplasmic reticulum that produce lipids and performs a variety of other specialized function such as breaking down drugs and alcohol

the golgi apparatus

closely layered stacks of membrane-enclosed spaces that process, sort, and deliver proteins


small membrane-bound sacs that divide some materials from the rest of the cytoplasm and transport these materials from place to place within the cell also called blebs


the powerhouse of the cell that supplies energy to the cell, has its own ribosomes and DNA


a fluid-filled sac used for the storage of materials needed by a cell

central vacuole

a vacuole that is in a plant that usually takes up most of the space inside a plant cell


suicide sacks that are produced by the golgi body that consists of a single membrane surrounding powerful digestive enzymes, that act as a clean up crew for the cell


a small region of cytoplasm that produces microtubules, and in animal cells, it contains two small structures called centrioles


cylinder-shaped organelles made of short microtubules arranged in a circle, the two centrioles are perpendicular to each other and they function in cell division. They have 0 groups of 3 arrangement of the protein fibers

cell wall

a rigid layer in plants, algae, fungi, and most bacteria, that surrounds the cell membrane which gives protection, support, and shape to the cell


organelles that carry out photosynthesis, a series of complex chemical reactions that convert solar energy into energy-rich molecules the cell can use


an individual living thing


a group of the same species that lives in one area


a group of different species that live together in one area


all of the organisms as well as the climate, soil, water, rocks, and other nonliving things in a given area


a major regional or global community of organisms, usually classified by the climate conditions and plant communities

biotic factors

living thing, such as plants, animals, fungi, and bacteria

abiotic factors

nonliving things such as moisture, temperature, wind, sunlight, and soil


the assortment, or variety of living things in an ecosystem

keystone species

a species that has an unusually large effect on its ecosystem


organisms that get their energy from nonliving resources, meaning they make their own food, also called autotrophs


organisms that get their energy by eating other living or once-living resources, such as plants and animals, also called heterotrophs


the process by which an organism forms carbohydrates using chemicals, rather than light, as an energy source

food chain

a sequence that links species by their feeding relationships, this model chain only follows the connection between one producer and a single chain of consumers within an ecosystem


organisms that eat only plants


organisms that eat only animals


organisms that eat both plants and animals


organisms that eat detritus, or dead organic matter


detritivores that break down organic matter into simpler compound


a consumer that eats one specific organism or feed on a very small number of organisms


consumers that have a varying diet

trophic levels

the levels of nourishment in a food chain

food web

a model that shows the complex network of feeding relationships and the flow of energy within and sometimes beyond an ecosystem


all of the biotic and abiotic factors in the area where an organism lives, these factors include all aspects of the environment, including the grass, the trees, and the watering holes (where a species lives)

ecological niche

all of the physical, chemical, and biological factors that a species needs to survive, stay healthy, and reproduce (how a species lives within its habitat)

competitive exclusion

when two species are competing for the same resources, one species will be better suited to the niche, and the other species will be pushed into another niche or become extinct

ecological equivalents

species that occupy similar niches but live in different geographical regions


occurs when two organisms fight for the same limited resources

interspecific competition

occurs when two different species compete for a limited resource, such as space


when individuals of a particular species struggle against one another for limited resources


the process by which one organism captures and feeds upon another organism


a close ecological relationship between two or more organisms of different species that live in direct contact with one another


an interspecies interaction in which both organisms benefit from one another


a relationship between two organisms in which one receives an ecological benefit from another, while the other neither benefits nor is harmed


a relationship similar to predation in that one organism benefits while the other is harmed


a parasite that makes its home on the exterior of an organism, attaching itself to the outside of the host and usually feeding on its fluids


a parasite that lives in the tissues and organs of a host where, safely hidden, they feed on the nutrients ingested by their host

population density

a measurement of the number of individuals living in a defined space

population dispersion

the way in which individuals of a population are spread in an area or a volume

clumped dispersion

individuals may live close together in groups in order to facilitate mating, gain protection, or access food resources

uniform dispersion

territorialitty and intraspecies competition for limited resources lead to individuals living at specific distances from one another

random dispersion

individuals are spread randomly within an area of a volume

survivorship curve

a generalized diagram showing the number of surviving members over time from a measured set of births


the movement of individuals into a population from another population


the movement of individuals out of a population and into another population

expotential growth

occurs when a population size increases dramatically over a period of time

logistic growth

when a population begins with a period of slow growth followed by a brief period of exponential growth before leveling off at a stable size

carrying capacity

the maximum number of individuals of a particular species that the environment can normally and consistently support

population crash

a dramatic decline in the size of a population over a short period of time

limiting factor

the factor that has the greatest effect in keeping down the size of a population

density-dependent limiting factors

limiting factors that are affected by the number of individuals in a given area

density-independent limiting factors

the aspects of the environment that limit a population's growth regardless of the density of the population


the sequence of biotic changes that regenerate a damaged community or create a community in a previously uninhabited area

primary succession

the establishment and development of an ecosystem in an area that was previously uninhabited

pioneer species

the first organisms that live in a previously uninhabited area

secondary succession

the reestablishment of a damaged ecosystem in an area where the soil was left intact


the branch of molecular biology that studies the use of microorganisms to perform specific industrial processes


single-celled organisms swimming a drop of pond water observed by Leeuwenhoek

spontaneous generation

the supposed production of living organisms from nonliving matter, as inferred from the apparent appearance of life in some infusions


an eyelash, or a delicate hairlike structure that resembles one

tropical rain forest

this biome has warm temperatures and abundant rainfall occur all year

tropical grassland

this biome has temperatures are warm throughout the year, with definite dry and rainy seasons

temperate grassland

this biome is dry and warm during the summer; most precipitation falls as snow during the winter


this biome has a very dry climate

temperate rain forest

this biome has one long wet season and a relatively dry summer


this biome has long, cold winters and short, warm, humid summers


subzero temperatures are the norm during the long winter, and there is little precipitation for this biome


the uppermost branches of trees


plants that grow above the ground on the branches of trees

Robert Brown

scottish botanist who discovered the cell nucleus


an area where the primary plant life is grass

deciduous trees

trees that have adapted to winter temperatures by dropping their leaves and going dormant during the season

coniferous trees

trees that retain their needles all year

habitat fragmentation

something that occurs when a barrier forms the prevents an organism from accessing its entire home range

introduced species

any organism that was brought to an ecosystem as the result of human actions


proteins made by B cells that destroy pathogens


red blood cell


white blood cell

binomial nomenclature

a system that gives each species a two-part scientific name using Latin words


first part of the scientific name which includes one ore more physically similar species that are thought to be closely related


a group of organisms so similar to one another that they can reproduce and have fertile offspring

Carlous Linnaeus

the father of taxonomy

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