Living Environment Vocabulary Words

abiotic

nonliving parts of the environment

active transport

the process by which cells use energy to transport molecules through the cell membrane from areas of low concentration to areas of high concentration.

adaptive value

any trait that helps an organism survive and reproduce under the given set of environmental conditions.

AIDS

(acquired immunodeficiency syndrome) the disease that results when the HIV virus attacks the human immune system.

allergy

a condition in which a person's immune system is overly sensitive to environmental substances that are normally harmless.

amino acid

any one of several building blocks of protein

antibiotic

a medicine produced by microorganisms used to destroy pathogens in humans and domestic animals.

antibody (pl. antibodies)

a protein, produced by the immune system, that either attacks invading pathogens or marks them for killing.

antigen

a molecule found on the outer surfaces of cells that the immune system recognizes as either part of the body or an outside invader.

asexual reproduction

a method of reproduction in which all the genes passed on to the offspring come from a single individual or parent.

assumption

something accepted as true that may or may not actually be true.

ATP

a compound that stores energy in cells.

autotroph

an organism that produces its own food: the source of energy for all the other living things on the earth.

bacterium

anyone of many single cell organism without a distinct nucleus.

balance

a tool that measures mass by comparing the unknown mass of an object with an object of known mass.

bias

a tendency to favor something prejudice.

biochemical process

a chemical process that occurs in living thing.

biodiversity

the variety of species in an area.

biosphere

all of Earth's ecosystems, collectively, the biologically inhabited portions of Earth, including all of the water, land, and air in which organisms survive.

biotechnology

the combination of technology and biological sciences

biotic

the living parts of the environment

body cells

non-reproductive cells in an individual such as skin, liver, and muscle cells; body cells contain the full number of chromosomes typical of the species.

bond

the chemical link between atoms that hold molecules together

carnivore

an organism that survives by eating animals

carrying capacity

the largest population of any single species that an area can support

catalyst

a substances that can speed up the rate of a chemical reaction without being changed or used up during the reaction

cell

the basic unit of structure and function that makes up all organisms

cell membrane

the thin boundary between the call and its environment

cellular respiration

the process in which nutrients are broken apart,releasing the chemical energy stored in them.

chloroplast

the green organelle that contains chlorophyll; where photosynthesis takes place

chromstography

a laboratory technique used to separate mixtures of molecules.

chromosome

a thick, threadlike structure that contains genetic information in the form of DNA

circulation

the flow of materials within a cell as well as between part of multicellular organism.

clone

an organism that is genetically identical to the organism from which it was produced.

cloning

a technique used to make identical organisms

community

a combination of all the different populations that live and interact in the same environment.

competition

the struggle between organisms for the same limited resources in a particular area.

compound light microscope

a tool that uses more than one lens and a light source to magnify an object

conclusion

the decision made about the outcome of an experiment usually based on how well the actual result matches the predicted result.

consumer

an organism that obtains the energy from producers

control

that group in an experiment in which everything - except the variable to be tested - is identical; the standard of comparison in an experiment

controlled experiment

an experiment in which all variables - except for the one being tested - are exactly the same.

cytoplasm

the jellylike substance that is between the cell membrane and the nucleus and that contains specialized structures.

data

the results of specific trials or tests completed during experiments

decomposer

an organism, generally a bacterium or fungus, that consumes dead organisms and organic waste.

deforestation

forest destruction that results from human activity

dependent variable

the part of an experiment that is changed to test a hypothesis.

development

the changes that occur from the fertilized egg to a complete individual; occurs by mitosis and differentiation of cells.

dichotomous key

a guide that compares pairs of observable traits to help the user identify an organism

differentiation

the process that transforms developing cells into specilized cells with different structures and functions

diffusion

the movement of molecules from areas of high concentration to areas of low concentration

digestion

the process that breaks down large food molecules into simpler molecules that the organism can use.

direct harvesting

the destruction of an organism, or the removal of an organism from its habitat

disease

a condition, other than injury, that prevents the body from working as it should.

dissection

the act of cutting apart a dead organism to examine its internal structure

DNA

(deoxyribonucleic acid) the material found in all cells that contains genetic information about that organism

dynamic equilibrium

the constant small corrections that normally occur to keep an organisms's internal environment within the limits needed for survival.

ecological succession

the process by which an existing community is replaced by another community

ecology

the study of how living things interact with one another and with their environment

ecosystem

all the living and nonliving things that interact in a specific area; a subdivision of the environment.

egg

a sex cell produced by a female

electronic balance

a balance that measures mass automatically

electrophoresis

a tool that allows scientists to separate mixtures of molecules according to size

element

a substance consisting of only one kind of atom

embryo

an organism in the early stages of development (prior to birth)

energy flow

the movement of energy through an ecosystem

energy pyramid

a diagram showing how food energy moves through the ecosystem

environment

every living and nonliving thing that surrounds an organism

enzymes

proteins that speed up the rate of chemical reactions in living things

equilibrium

a state of balance and stability

evidence

support for the idea that something is true

evolution

the process by which species have changed over time

excretion

the removal of all the wastes produced by the cells of the body

experiment

a series of trials or tests that are done to support or refute a hypothesis

expressed

the way that an unseen gene is seen in an organism as an actual physical trait

extinction

the disappearance of all members of a species from earth

feedback mechanism

a cycle in which the output of a system either modifies or reinforces the first action taken by the system.

fertilization

the process that combines a sperm cell and an egg cell

fetus

the unborn, developing young of an animal during the later stages of development.

finite

limited; able to be used up; opposite of infinite

food chain

a representation that identifies the specific feeding relationships among organisms

food web

a representation of many interconnected food chains that shows the feeding relationships among producers, consumers and decomposers.

fossil

the preserved remains of ancient organisms

fossil fuel

a feud, such as coal and gas, that comes from the remains of organisms that lived millions of years ago

fossil record

a collection of fossils used to represent Earth's history

fungus (pl. fungi)

the kingdom of organisms that are mostly multicellular, have cell walls made of chitin, and are heterotrophic

gamete

an egg or sperm cell; a sex cell

gas exchange

the process of obtaining oxygen oxygen from the environment and releasing carbon dioxide

gene (pl. genes)

a segment of DNA (on a chromosome) that contains the code for a specific trait

gene expression

see expressed; the result of activated genes

genetic recombination

the formation of a new combination of genes during sexual reproduction

genetic variation

the normal differences found among offspring

geological time

Earth's history as revealed by layers of rock

global warming

a increase in Earth's average surface temperature caused by an increase in green house gases

glucose

a sugar that is a major source of energy for cells

graduated cylinder

a tool used to measure the volume of a liquid

greenhouse effect

the trapping of heat by gases in the atmosphere

greenhouse gas

an atmospheric gas that traps heat

growth

an increase in the size or number cells

guard cell

specialized cells that control the opening and closing of the pores on the surface of a leaf