Glossary

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A Abiotic - non-living things in an environment Achaebacteria - kingdom of bacteria that live in extreme conditions Active Transport - the movement of molecules across the cell membrane with the use of cellular energy Adaptation - any special characteristic or feature that makes the animal or plant especially suited for the climate and geological features of the biome in which they live Aerobic Respiration - cellular respiration that occurs with abundant oxygen for use by the cell Airborne Viruses - viruses that are transmitted through the air Allantois - a fluid-filled sac that is attached to the embryo's gut; It collects waste (urine-like) as the embryo develops Alleles - the different forms that genes can be Amber - hardened, petrified tree sap, often containing fossilized insects Amnion - the fluid-filled sac that surrounds the embryo; it protects and prevents dehydration of the embryo Anaphase - the stage of mitosis where the chromosomes are moved to the opposite ends of the cells Animal - organisms that are heterotrophic, multicellular with eukaryote cells, and no cell wall Animal Kingdom - multi-cellular; eukaryotes (no cell wall); heterotrophs; examples—seahorse, goldfish, snakes, eagle, human Anterior - refers to the area of an animal in the front or head region Antibodies - molecules made by the body's white blood cells; these molecules contain proteins to destroy viruses, bacteria, or other harmful toxins Arteries - blood vessels that carry oxygenated blood away from the heart Atrium - smaller upper chamber in a heart; receives blood from the body's blood vessels then pumps blood to a ventricle or away from the heart Autotrophs - living things that can convert energy directly from the sun, or in some cases, use environmental chemicals to make energy for their bodily processes

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B Bacillus Bacteria - rod-shaped bacteria Binary Fission - a type of asexual reproduction in which a bacterial cell divides by mitosis resulting in offspring that are genetically identical to the parent bacterium Biodiversity - the variety of living things on earth that help keep a natural balance Biology - the study of life or living things Biome - an area on our earth that shares the same climate and species of animals and plants Biosphere - the part of earth and its atmosphere that can support life Biotic - living organisms

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C Cancer - a disease caused by rapid uncontrolled cellular division Carbohydrates - large molecules in living things that are sugars and used as an energy source Carnivores - only eat animals Carrying Capacity - the maximum number of organisms that the ecosystem can support Casts - a trace replica of an organism in which the mold has been filled in with rock and is stripped away, leaving the cast Cell Membrane - an organelle found in all cells that controls the transportation into and out of the cell Cell Wall - an organelle in some cells that surrounds the outside of the cell membrane and is used for protection Cellular Respiration - organisms here on land and in water give off carbon dioxide as their bodies process and use the energy in the carbon rich food Chloroplast - an organelle found in cells that can do photosynthesis; it contains chlorophyll Chorion - the outer most membrane; it functions to allow gas exchange between oxygen and carbon dioxide Chromosomes - a large strand of DNA that typically contains more than a 1000 genes Climate - the combination of expected temperature, sunlight, wind, and precipitation over an extended length of time Climax Community -a community with little or no change Clone - an offspring who is genetically identical as parent Coccus Bacteria - spherical-shaped bacteria Community - an area occupied by different groups of interacting organisms Compound Microscope - uses a couple of lenses and a light source to help magnify an object; can magnify up to around 1500 times. Condensation - when the water vapor rises into the atmosphere, eventually cooling, forming clouds Conjugation - a type of sexual reproduction in bacteria in which all or part of the bacterial genetic information is exchanged resulting in genetically varied bacteria Conservation - the actions we take to save or protect the Earth's resources Consumers - consume other organisms for their energy Cytoplasm - a gel-like substance that cushions the organelles inside the cell and contains many chemical reactions

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D Decomposers - break down and absorb nutrients from things like fallen leaves, feces, and dead animals and plants Diffusion - random movement of molecules from a high concentration to a lower concentration Digestion - the process in which food is broken down into elements and nutrients that can be used by cells Diploid - cell with the total number of chromosomes in the body cells DNA - contains the information for making proteins in the cells and ensures that the information is passed to new cells and new offspring Dominant Allele - a trait that prevents the showing of other traits. It is a gene that is fully expressed when two different alleles are present Dorsal - refers to the surface of an animal closest to the spinal column; the back

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E Ecology - the study of the interactions between living organisms and the non-living parts of the environment Ecosystem - formed by the interaction of a community of organisms with their physical environment Ectothermic - an animal is called an ectotherm when their body temperature is controlled by the temperature of their surroundings; for example, a frog's temperature remains only a few degrees different than the water or air that surrounds them Electron Microscope - uses a beam of electrons and magnetic fields to produce an image of the object onto a computer screen Embryo - developing organism in very early stages Endospore - a hard outer covering that can protect bacteria from drying out, heat (even boiling water), and harsh chemicals Endothermic - when the body temperature of an animal is controlled internally and remains fairly constant despite changes in the external, environmental temperature Energy - the usable power required for many of life's functions to occur in an organism Energy pyramid - shows the different trophic, or feeding levels, in relation to the amount of energy and biomass available in that level. In this model the total amount of energy available, and biomass, is largest at the bottom of the pyramid, in the producer level Enzymes - a special type of protein that controls all of cells chemistry Eubacteria - kingdom of bacteria we consider the "common" types that live in common places, like your mouth and the surfaces of sinks Eukaryote Cell - cells with membrane-bound organelles Evaporation - when water is heated by the sun and turns back into a gas called water vapor Evolution - change over time, includes the theories of microevolution and macroevolution Exoskeleton - a hard, external (on the outside) covering made of chitin; the function of the exoskeleton is to protect the soft internal parts and prevent them from drying out Experiment - a procedure that is set up to test a hypothesis.

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F Fins - structures used by fish to help them move through water and stay balanced Flagella - a long fibrous tail-like structure used to help cells move Food Chain - shows the feeding and energy relationships in a chain like progression from producers to the top level consumers. The feeding relationship is shown by movement to the right on the chain and the energy relationships are shown by the arrow size getting smaller as you go up the food chain to the highest trophic levels Food Web - shows all possible feeding relationships in an ecosystem; it is the big picture Fossils - any evidence or remains of plants or animals from the past Fungi Kingdom - multi-cellular (except for yeast); eukaryotes (with a cell wall made up of chitin); heterotroph; examples—molds and mushrooms

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G Gametes - sperm or eggs that contain half the number of chromosomes as the body cells Genes - segments of DNA that contain information that help make up our inside and outside characteristics Genetics - the study of heredity Genotype - what your chromosomes say your features are Genus - a general group of one type or kind of organism; such as the genus of cat-like animals—lions, tigers, domestic cats, and so on; also the first name of an organism's scientific name Greenhouse Effect - a natural warming process on earth, caused in part by too much carbon dioxide in the air

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H Habitat - where the organism lives or the place in the ecosystem that it inhabits Haploid - cell with half the number of chromosomes as the body cells Herbivores - only eat plants Heredity - the transfer of genes to offspring through sexual reproduction Hermaphrodite - an organism, like the invertebrate earthworm, that has both male and female reproductive organs in one animal and therefore produces both eggs and sperm; sexual reproduction then occurs between two worms during which there is an exchange of egg and sperm Heterotrophs - organisms that must eat or consume other organisms, plants, animals, or both, to get their energy Heterozygous - a trait produced from two different alleles Homeostasis -a natural balance that all living things must maintain Homozygous - a trait produced from two alleles that are alike Host Cell - a cell that a virus has entered and taken control of for reproductive purposes Hyphae - cells that make up the body of the fungus; also function in absorption of nutrients from food sources Hypothesis - a prediction that is based on the information that you gathered.

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I Immunization - a treatment, usually exposure to the "live" virus through a shot, to create an immune response in the body so that a peson is not affected by the virus and does not get sick; immunizations, often in the form of a shot, help the body have an immune response to the virus; helping them "fight off" an actual infection Imprints - the trace of an organism in which only a light outline of features is left in the rock, like the profile of a leaf or fish Invertebrates - animals without backbones; examples are jellyfish and worms

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J

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K Karyotype - the complete set of all chromosomes (one set from Mom and one set from Dad) arranged and displayed by size Kingdom - in the classification of organisms, this is the largest group; there are six kingdoms

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L Limiting Factors - anything (biotic or abiotic) that controls (or limits) the number and kinds of organisms living in a given area Lipids - large molecules in living things are fats and used as energy storage Lysosome - an organelle that contains digestive enzymes and helps to digest waste inside the cell

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M Macroevolution - evolution that deals with an organism changing and developing into a new species Meiosis - cellular division that produces gametes with half the number of chromosomes Metamorphosis - in amphibians, it is the change from the pre-adult form that lives in the water to the adult form that lives on land. Metaphase - phase of mitosis where the chromosomes line up in the middle of the cell Microevolution - evolution that involves changes in a species over time to produce adaptations that allow the organism to better survive in its environment Mitochondria - an organelle that functions to make cellular energy Mitosis - the process where a cell divides and the outcome is two identical cells Molds (Fossil) - the trace of an organism that is an empty space in the rock, but reflects the shape of the organism Mutation - a change in DNA

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N Natural Selection - when organisms that live and survive through environmental change pass their characteristics to their offspring, and the species "adapts" to the environment; normally these changes, or adaptations, occur very slowly over time Nervous System - nerves, a brain (in most cases) and sense organs, like eyes and touch receptors, that send messages about the environment to the animal so it can respond accordingly Neuron - one nerve cell Niche - an organism's contribution to its environment and community Nitrogen Fixation - bacteria in soil can convert nitrogen into a form that living things can process Nucleic Acid - the genetic material of the cell Nucleotide - a nitrogenous base, sugar, and phosphate Nucleus - an organelle that contains the DNA of the cell

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O Omnivores - eat both plants and animals Organelles - the parts of a cell Osmosis - diffusion of water molecules across a semi-permeable membrane

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P Paleontologists - scientists who study ancient life Parasitic Organism - a parasitic organism needs a host or hosts, to complete their reproductive phase; they cause harm to their host organism Passive Transport - the movement of molecules across the cell membrane without the use of cellular energy Person to Person Viruses - viruses that are transmitted through contact with a person who has the virus; can include touch of the skin where the virus resides, or through exchage of bodily fluids as with HIV Petrified Fossils - a stone copy of an organism, where minerals from the ground have replaced some parts of the organism Phenotype - what the trait looks like Photosynthesis - the process of converting the sun's energy to a usable form; producers (plants) take in light energy from the sun, water from the ground, and carbon dioxide from the air and make the carbon rich food (carbohydrates) that consumers eat Plant Kingdom - multi-cellular; eukaryotes with a cell wall made of cellulose; autotrophs Population - a group of similar organisms that occur in a specific geographical area Posterior - refers to the area of an animal in the tail or rear region Precipitation - rain, snow or hail Primary Succession - natural change that takes place on newly formed surfaces Producers - organisms that bring new energy to the ecosystem and provide energy for other organisms that eat them Products - chemicals that result from the reaction Prophase - the stage of mitosis where the nucleus gets ready to separate. Proteins - large molecules in living things that are made up of amino acids and is used for the makeup of cell structures Protist Kingdom - single-cellular or multi-cellular; eukaryotes—some have cell walls and some do not; some are autotroph and some are heterotroph; examples: amoeba, slime-mold and algae Punnett squares - are a picture representation for predicting what offspring will look like

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Q

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R Reactants - the substances that the reaction processes start with Recessive Allele - a trait that is hidden by a dominant trait. It is a gene that is not expressed when paired with a dominant allele Respiratory System - the combination of all organs and tissues in an animal that are involved in gas exchange Ribosome - organelle used to help make proteins

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S Scales - structures on fish that allow them to be more streamlined, and reduce friction as they move through water Science - a Latin word 'scientia' meaning 'knowledge'. A process by which problems and questions about the natural world are solved and answered AND a body of knowledge that results from the process of science. Scientific Law - a conclusion that is made based on repeated scientific experimentation over many years and has become universally accepted by the scientific community Scientific Method - a basic process that people follow to solve problems and gain new knowledge. Secondary Succession - natural change that takes place in an existing ecosystem that has been disturbed by some event Semi-permeable Membrane - allows some things to pass through but not all Sessile Animals - an animal that remains attached to one place their entire adult lives Sexual Reproduction - produces offspring from two parents Spawning - a type of external reproduction where a large number of sperm and eggs are released into the water at the same time Species - in the classification of organisms, this is the most specific group, including one kind of organism that can successfully reproduce with each other; also used as the second name in an organism's scientific name Spirillum Bacteria - spiral-shaped bacteria Spore - a reproductive cell (sexual) that can develop into fungus if it lands in the right conditions Swim Bladder - an internal organ that fills and releases gas to allow fish to be buoyant (move up and down)

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T Taxonomy - the classification of organisms Telophase - the time in mitosis when a nucleus begins to reform around the chromosomes at the end of each cell Theory - a proposed set of statements or principles used to explain a group of facts or natural phenomena; evidences that support the theory Trace Fossils - a fossil that is a part of, or evidence of, an organism from the past Traits - the characteristics that are passed down from parents

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U

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V Vacuole - an organelle inside a cell that is used to store material like food and water Veins - blood vessels that carry blood from the body cells toward the heart Ventral - refers to the surface of an animal farthest from the spinal column; the belly Ventricle - Large, lower chamber in a heart; pumps blood to the atrium Vertebrates - animals with backbones; examples are dogs,snakes, zebras, and humans Viruses - viruses are non cellular entities that cause diseases

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W

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X

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Y Yolk - a sac that is attached to the embryo that supplies food

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Z

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