• Shuffle
    Toggle On
    Toggle Off
  • Alphabetize
    Toggle On
    Toggle Off
  • Front First
    Toggle On
    Toggle Off
  • Both Sides
    Toggle On
    Toggle Off
  • Read
    Toggle On
    Toggle Off
Reading...
Front

How to study your flashcards.

Right/Left arrow keys: Navigate between flashcards.right arrow keyleft arrow key

Up/Down arrow keys: Flip the card between the front and back.down keyup key

H key: Show hint (3rd side).h key

A key: Read text to speech.a key

image

Play button

image

Play button

image

Progress

1/170

Click to flip

170 Cards in this Set

  • Front
  • Back
adaptation
Inherited characteristic of an organism that enhances its survival and reproduction in specific environments.
anaerobic respiration
The use of inorganic molecules other than oxygen to accept electrons at the “downhill” end of electron transport chains.
autotroph
An organism that obtains organic food molecules without eating other organisms or substances derived from other organisms. Autotrophs use energy from the sun or from the oxidation of inorganic substances to make organic molecules from inorganic ones.
Bacteria
One of two prokaryotic domains, the other being Archaea.
binary fission
A method of asexual reproduction by “division in half.” In prokaryotes, binary fission does not involve mitosis; but in single-celled eukaryotes that undergo binary fission, mitosis is part of the process.
biofilm
A surface-coating colony of one or more species of prokaryotes that engage in metabolic cooperation.
bioremediation
The use of organisms to detoxify and restore polluted and degraded ecosystems.
capsule
(1) A sticky layer that surrounds the cell wall of some prokaryotes, protecting the cell surface and sometimes helping to glue the cell to surfaces. (2) The sporangium of a bryophyte (moss, liverwort, or hornwort).
chemoautotroph
An organism that needs only carbon dioxide as a carbon source but obtains energy by oxidizing inorganic substances.
chemoheterotroph
An organism that must consume organic molecules for both energy and carbon.
commensalism
A symbiotic relationship in which one organism benefits but the other is neither helped nor harmed.
conjugation
In prokaryotes, the direct transfer of DNA between two cells (of the same or different species) that are temporarily joined. In ciliates, a sexual process in which two cells exchange haploid micronuclei.
cooperativity
A kind of allosteric regulation whereby a shape change in one subunit of a protein caused by substrate binding is transmitted to all the others, facilitating binding of subsequent substrate molecules.
decomposer
An organism that absorbs nutrients from nonliving organic material such as corpses, fallen plant material, and the wastes of living organisms and converts them to inorganic forms; a detritivore.
endospore
A thick-coated, resistant cell produced by a bacterial cell exposed to harsh conditions.
adaptive radiation
Period of evolutionary change in which groups of organisms form many new species whose adaptations allow them to fill vacant ecological roles in their communities.
ATP (adenosine triphosphate)
An adenine-containing nucleoside triphosphate that releases free energy when its phosphate bonds are hydrolyzed. This energy is used to drive endergonic reactions in cells.
Archaea
One of two prokaryotic domains, the other being Bacteria.
archaean
Member of the prokaryotic domain Archaea.
bioinformatics
The use of computers, software, and mathematical models to process and integrate biological information from large data sets.
controlled experiment
An experiment in which an experimental group is compared with a control group that varies only in the factor being tested.
data
Recorded observations.
deductive reasoning
A type of logic in which specific results are predicted from a general premise.
deoxyribonucleic acid (DNA)
A double-stranded, helical nucleic acid molecule consisting of nucleotide monomers with a deoxyribose sugar and the nitrogenous bases adenine (A), cytosine (C), guanine (G), and thymine (T); capable of replicating and determining the inherited structure of a cell’s proteins.
emergent properties
New properties that arise with each step upward in the hierarchy of life, owing to the arrangement and interactions of parts as complexity increases.
Eukarya
The domain that includes all eukaryotic organisms.
eukaryotic cell
A type of cell with a membrane-enclosed nucleus and membrane-enclosed organelles. Organisms with eukaryotic cells (protists, plants, fungi, and animals) are called eukaryotes.
evolution
Descent with modification; the idea that living species are descendants of ancestral species that were different from the present-day ones; also defined more narrowly as the change in the genetic composition of a population from generation to generation.
genome
The genetic material of an organism or virus; the complete complement of an organism’s or virus’s genes along with its noncoding nucleic acid sequences.
hypothesis
A tentative answer to a well-framed question, narrower in scope than a theory and subject to testing.
inductive reasoning
A type of logic in which generalizations are based on a large number of specific observations.
inquiry
The search for information and explanation, often focused by specific questions.
model
A representation of a theory or process.
negative feedback
A primary mechanism of homeostasis, whereby a change in a physiological variable triggers a response that counteracts the initial change.
order
In classification, the taxonomic category above the level of family.
positive feedback
A physiological control mechanism in which a change in a variable triggers mechanisms that amplify the change.
prokaryotic cell
A type of cell lacking a membrane-enclosed nucleus and membrane-enclosed organelles. Organisms with prokaryotic cells (bacteria and archaea) are called prokaryotes.
systems biology
An approach to studying biology that aims to model the dynamic behavior of whole biological systems.
technology
The application of scientific knowledge for a specific purpose, often involving industry or commerce but also including uses in basic research.
endotoxin
A toxic component of the outer membrane of certain gram-negative bacteria that is released only when the bacteria die.
extreme halophile
An organism that lives in a highly saline environment, such as the Great Salt Lake or the Dead Sea.
extreme thermophile
An organism that thrives in hot environments (often 60–80°C or hotter).
extremophile
An organism that lives in an environment whose conditions are so extreme that few other species can survive there. Extremophiles include extreme halophiles and extreme thermophiles.
F factor
In bacteria, the DNA segment that confers the ability to form pili for conjugation and associated functions required for the transfer of DNA from donor to recipient. The F factor may exist as a plasmid or be integrated into the bacterial chromosome.
F plasmid
The plasmid form of the F factor.
facultative anaerobe
An organism that makes ATP by aerobic respiration if oxygen is present but that switches to anaerobic respiration or fermentation if oxygen is not present.
fimbria
A short, hairlike appendage of a prokaryotic cell that helps it adhere to the substrate or to other cells; also known as an attachment pilus.
Gram stain
A staining method that distinguishes between two different kinds of bacterial cell walls.
gram-negative
Describing the group of bacteria that have a cell wall that is structurally more complex and contains less peptidoglycan than the cell wall of gram-positive bacteria. Gram-negative bacteria are often more toxic than gram-positive bacteria.
gram-positive
Describing the group of bacteria that have a cell wall that is structurally less complex and contains more peptidoglycan than the cell wall of gram-negative bacteria. Gram-positive bacteria are usually less toxic than gram-negative bacteria.
heterocyte
A specialized cell that engages in nitrogen fixation in some filamentous cyanobacteria; formerly called heterocyst.
heterotroph
An organism that obtains organic food molecules by eating other organisms or substances derived from them.
horizontal gene transfer
The transfer of genes from one genome to another through mechanisms such as transposable elements, plasmid exchange, viral activity, and perhaps fusions of different organisms.
host
The larger participant in a symbiotic relationship, serving as home and food source for the smaller symbiont.
methanogen
An organism that obtains energy by using carbon dioxide to oxidize hydrogen, producing methane as a waste product; all known methanogens are in domain Archaea.
mutualism
A symbiotic relationship in which both participants benefit.
nitrogen fixation
The conversion of atmospheric nitrogen (N2) to ammonia (NH3). Biological nitrogen fixation is carried out by certain prokaryotes, some of which have mutualistic relationships with plants.
nucleoid
A dense region of DNA in a prokaryotic cell.
obligate aerobe
An organism that requires oxygen for cellular respiration and cannot live without it.
obligate anaerobe
An organism that only carries out fermentation or anaerobic respiration. Such organisms cannot use oxygen and in fact may be poisoned by it.
parasite
An organism that feeds on the cell contents, tissues, or body fluids of another species (the host) while in or on the host organism. Parasites harm but usually do not kill their host.
parasitism
A symbiotic relationship in which one organism, the parasite, benefits at the expense of another, the host, by living either within or on the host.
pathogen
An organism or virus that causes disease
peptidoglycan
A type of polymer in bacterial cell walls consisting of modified sugars cross-linked by short polypeptides.
photoautotroph
An organism that harnesses light energy to drive the synthesis of organic compounds from carbon dioxide.
photoheterotroph
An organism that uses light to generate ATP but must obtain carbon in organic form.
R plasmid
A bacterial plasmid carrying genes that confer resistance to certain antibiotics.
symbiont
The smaller participant in a symbiotic relationship, living in or on the host.
symbiosis
An ecological relationship between organisms of two different species that live together in direct and intimate contact.
taxis
An oriented movement toward or away from a stimulus.
transduction
(1) A type of horizontal gene transfer in which phages (viruses) carry bacterial DNA from one host cell to another. (2) In cellular communication, the conversion of a signal from outside the cell to a form that can bring about a specific cellular response.
transformation
(1) The conversion of a normal animal cell to a cancerous cell. (2) A change in genotype and phenotype due to the assimilation of external DNA by a cell.
alternation of generations
A life cycle in which there is both a multicellular diploid form, the sporophyte, and a multicellular haploid form, the gametophyte; characteristic of plants and some algae.
alveolate
A protist with membrane-bounded sacs (alveoli) located just under the plasma membrane.
amoeba
A protist grade characterized by the presence of pseudopodia.
amoebozoan
A protist in a clade that includes many species with lobe- or tube-shaped pseudopodia.
apicomplexan
A protist in a clade that includes many species that parasitize animals. Some apicomplexans cause human disease.
Archaeplastida
One of five supergroups of eukaryotes proposed in a current hypothesis of the evolutionary history of eukaryotes. This monophyletic group, which includes red algae, green alage, and land plants, descended from an ancient protist ancestor that engulfed a cyanobacterium. See also Excavata, Chromalveolata, Rhizaria, and Unikonta.
blade
(1) A leaflike structure of a seaweed that provides most of the surface area for photosynthesis. (2) The flattened portion of a typical leaf.
brown alga
A multicellular, photosynthetic protist with a characteristic brown or olive color that results from carotenoids in its plastids. Most brown algae are marine, and some have a plantlike body (thallus).
cellular slime mold
A type of protist that has unicellular amoeboid cells and aggregated reproductive bodies in its life cycle.
Chromalveolata
One of five supergroups of eukaryotes proposed in a current hypothesis of the evolutionary history of eukaryotes. Chromalveolates may have originated by secondary endosymbiosis and include two large protist clades, the alveolates and the stramenopiles. See also Excavata, Rhizaria, Archaeplastida, and Unikonta.
ciliate
A type of protist that moves by means of cilia.
coral reef
Typically a warm-water, tropical ecosystem dominated by the hard skeletal structures secreted primarily by the resident cnidarians. Some reefs also exist in cold, deep waters.
cytoplasmic streaming
A circular flow of cytoplasm, involving myosin and actin filaments, that speeds the distribution of materials within cells.
diatom
A unicellular photosynthetic alga with a unique glassy cell wall containing silica.
dinoflagellate
Member of a group of mostly unicellular photosynthetic algae with two flagella situated in perpendicular grooves in cellulose plates covering the cell.
diplomonad
A protist that has modified mitochondria, two equal-sized nuclei, and multiple flagella.
euglenid
A protist, such as Euglena or its relatives, characterized by an anterior pocket from which one or two flagella emerge.
euglenozoan
Member of a diverse clade of flagellated protists that includes predatory heterotrophs, photosynthetic autotrophs, and pathogenic parasites.
Excavata
One of five supergroups of eukaryotes proposed in a current hypothesis of the evolutionary history of eukaryotes. Excavates have unique cytoskeletal features, and some species have an “excavated” feeding groove on one side of the cell body. See also Chromalveolata, Rhizaria, Archaeplastida, and Unikonta.
foram (foraminiferan)
An aquatic protist that secretes a hardened shell containing calcium carbonate and extends pseudopodia through pores in the shell.
golden alga
A biflagellated, photosynthetic protist named for its color, which results from its yellow and brown carotenoids.
heteromorphic
Referring to a condition in the life cycle of plants and certain algae in which the sporophyte and gametophyte generations differ in morphology.
holdfast
A rootlike structure that anchors a seaweed.
isomorphic
Referring to alternating generations in plants and certain algae in which the sporophytes and gametophytes look alike, although they differ in chromosome number.
kinetoplastid
A protist, such as a trypanosome, that has a single large mitochondrion that houses an organized mass of DNA.
mixotroph
An organism that is capable of both photosynthesis and heterotrophy.
oomycete
A protist with flagellated cells, such as a water mold, white rust, or downy mildew, that acquires nutrition mainly as a decomposer or plant parasite.
opisthokont
Member of the diverse clade Opisthokonta, organisms that descended from an ancestor with a posterior flagellum, including fungi, animals, and certain protists.
parabasalid
A protist, such as a trichomonad, with modified mitochondria.
plasmodial slime mold
A type of protist that has amoeboid cells, flagellated cells, and a plasmodial feeding stage in its life cycle.
plasmodium
A single mass of cytoplasm containing many diploid nuclei that forms during the life cycle of some slime molds.
producer
An organism that produces organic compounds from CO2 by harnessing light energy (in photosynthesis) or by oxidizing inorganic chemicals (in chemosynthetic reactions carried out by some prokaryotes).
protist
An informal term applied to any eukaryote that is not a plant, animal, or fungus. Most protists are unicellular, though some are colonial or multicellular.
pseudopodium
A cellular extension of amoeboid cells used in moving and feeding.
radiolarian
A protist, usually marine, with a shell generally made of silica and pseudopodia that radiate from the central body.
red alga
A photosynthetic protist, named for its color, which results from a red pigment that masks the green of chlorophyll. Most red algae are multicellular and marine.
redox reaction
A chemical reaction involving the complete or partial transfer of one or more electrons from one reactant to another; short for oxidation-reduction reaction.
Rhizaria
One of five supergroups of eukaryotes proposed in a current hypothesis of the evolutionary history of eukaryotes; a morphologically diverse protist clade that is defined by DNA similarities. See also Excavata, Chromalveolata, Archaeplastida, and Unikonta.
secondary endosymbiosis
A process in eukaryotic evolution in which a heterotrophic eukaryotic cell engulfed a photosynthetic eukaryotic cell, which survived in a symbiotic relationship inside the heterotrophic cell.
stipe
A stemlike structure of a seaweed.
stramenopile
A protist in which a “hairy” flagellum (one covered with fine, hairlike projections) is paired with a shorter, smooth flagellum.
thallus
A seaweed body that is plantlike, consisting of a holdfast, stipe, and blades, yet lacks true roots, stems, and leaves.
Unikonta
One of five supergroups of eukaryotes proposed in a current hypothesis of the evolutionary history of eukaryotes. This clade, which is supported by studies of myosin proteins and DNA, consists of amoebozoans and opisthokonts. See also Excavata, Chromalveolata, Rhizaria, and Archaeplastida.
alternation of generations
A life cycle in which there is both a multicellular diploid form, the sporophyte, and a multicellular haploid form, the gametophyte; characteristic of plants and some algae.
angiosperm
A flowering plant, which forms seeds inside a protective chamber called an ovary.
antheridium
In plants, the male gametangium, a moist chamber in which gametes develop.
apical meristem
Embryonic plant tissue in the tips of roots and the buds of shoots. The dividing cells of an apical meristem enable the plant to grow in length.
archegonium
In plants, the female gametangium, a moist chamber in which gametes develop.
bryophyte
An informal name for a moss, liverwort, or hornwort; a nonvascular plant that lives on land but lacks some of the terrestrial adaptations of vascular plants.
cuticle
A waxy covering on the surface of stems and leaves that acts as an adaptation that prevents desiccation in terrestrial plants. (2) The exoskeleton of an arthropod, consisting of layers of protein and chitin that are variously modified for different functions. (3) A tough coat that covers the body of a nematode.
embryophyte
Alternate name for land plants that refers to their shared derived trait of multicellular, dependent embryos.
foot
(1) The portion of a bryophyte sporophyte that gathers sugars, amino acids, water, and minerals from the parent gametophyte via transfer cells. (2) One of the three main parts of a mollusc; a muscular structure usually used for movement. See also mantle, visceral mass.
gametangium
Multicellular plant structure in which gametes are formed. Female gametangia are called archegonia, and male gametangia are called antheridia.
gametophore
The mature gamete-producing structure of a moss gametophyte.
gametophyte
In organisms (plants and some algae) that have alternation of generations, the multicellular haploid form that produces haploid gametes by mitosis. The haploid gametes unite and develop into sporophytes.
grade
A group of organisms that share the same level of organizational complexity or share a key adaptation.
gymnosperm
A vascular plant that bears naked seeds—seeds not enclosed in specialized chambers.
heterosporous
Referring to a plant species that has two kinds of spores: microspores, which develop into male gametophytes, and megaspores, which develop into female gametophytes.
heterosporous
Referring to a plant species that has two kinds of spores: microspores, which develop into male gametophytes, and megaspores, which develop into female gametophytes.
homosporous
Referring to a plant species that has a single kind of spore, which typically develops into a bisexual gametophyte.
hornwort
A small, herbaceous nonvascular plant that is a member of the phylum Anthocerophyta.
leaf
The main photosynthetic organ of vascular plants.
lignin
A hard material embedded in the cellulose matrix of vascular plant cell walls that provides structural support in terrestrial species.
liverwort
A small, herbaceous nonvascular plant that is a member of the phylum Hepatophyta.
lycophyte
An informal name for a member of the phylum Lycophyta, which includes club mosses, spike mosses, and quillworts.
megaphyll
A leaf with a highly branched vascular system, characteristic of the vast majority of vascular plants.
megaspore
A spore from a heterosporous plant species that develops into a female gametophyte.
microphyll
In lycophytes, a small leaf with a single unbranched vein.
microspore
A spore from a heterosporous plant species that develops into a male gametophyte.
moss
A small, herbaceous nonvascular plant that is a member of the phylum Bryophyta.
mycorrhiza
A mutualistic association of plant roots and fungus.
peat
Extensive deposits of partially decayed organic material formed primarily from the wetland moss Sphagnum.
peristome
A ring of interlocking, tooth-like structures on the upper part of a moss capsule (sporangium), often specialized for gradual spore discharge.
phloem
Vascular plant tissue consisting of living cells arranged into elongated tubes that transport sugar and other organic nutrients throughout the plant.
phragmoplast
An alignment of cytoskeletal elements and Golgi-derived vesicles that forms across the midline of a dividing plant cell.
placental transfer cell
A plant cell that enhances the transfer of nutrients from parent to embryo.
Plantae
The kingdom that consists of multicellular eukaryotes that carry out photosynthesis.
protonema
A mass of green, branched, one-cell-thick filaments produced by germinating moss spores
pterophyte
An informal name for a member of the phylum Pterophyta, which includes ferns, horsetails, and whisk ferns and their relatives.
rhizoid
A long, tubular single cell or filament of cells that anchors bryophytes to the ground. Unlike roots, rhizoids are not composed of tissues, lack specialized conducting cells, and do not play a primary role in water and mineral absorption.
root
An organ in vascular plants that anchors the plant and enables it to absorb water and minerals from the soil.
seed
An adaptation of some terrestrial plants consisting of an embryo packaged along with a store of food within a protective coat.
seedless vascular plant
An informal name for a plant that has vascular tissue but lacks seeds. Seedless vascular plants form a paraphyletic group that includes the phyla Lycophyta (club mosses and their relatives) and Pterophyta (ferns and their relatives).
seta
The elongated stalk of a bryophyte sporophyte
sorus
A cluster of sporangia on a fern sporophyll. Sori may be arranged in various patterns, such as parallel lines or dots, which are useful in fern identification.
sporangium
A multicellular organ in fungi and plants in which meiosis occurs and haploid cells develop.
spore
(1) In the life cycle of a plant or alga undergoing alternation of generations, a haploid cell produced in the sporophyte by meiosis. A spore can divide by mitosis to develop into a multicellular haploid individual, the gametophyte, without fusing with another cell. (2) In fungi, a haploid cell, produced either sexually or asexually, that produces a mycelium after germination.
sporocyte
A diploid cell, also known as a spore mother cell, that undergoes meiosis and generates haploid spores.
sporophyll
A modified leaf that bears sporangia and hence is specialized for reproduction.
sporophyte
In organisms (plants and some algae) that have alternation of generations, the multicellular diploid form that results from the union of gametes. The sporophyte produces haploid spores by meiosis that develop into gametophytes.
sporopollenin
A durable polymer that covers exposed zygotes of charophyte algae and forms the walls of plant spores, preventing them from drying out.
stoma
A microscopic pore surrounded by guard cells in the epidermis of leaves and stems that allows gas exchange between the environment and the interior of the plant.
strobilus
The technical term for a cluster of sporophylls known commonly as a cone, found in most gymnosperms and some seedless vascular plants.
tracheid
A long, tapered water-conducting cell found in the xylem of nearly all vascular plants. Functioning tracheids are no longer living.
vascular plant
A plant with vascular tissue. Vascular plants include all living plant species except mosses, liverworts, and hornworts
vascular tissue
Plant tissue consisting of cells joined into tubes that transport water and nutrients throughout the plant body
xylem
Vascular plant tissue consisting mainly of tubular dead cells that conduct most of the water and minerals upward from the roots to the rest of the plant.
angiosperm
A flowering plant, which forms seeds inside a protective chamber called an ovary.