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199 Cards in this Set

  • Front
  • Back
Crop
plant cultivated for use by humans
Producer
organism that makes its own food from energy and carbon atoms in its environment; autothroph
Consumer
organism that must obtain energy to build its molecules by consuming other organisms; heterotroph
Food chain
liner pathway of energy transfer in an ecosystem
Cell respiration
process by which living things obtain energy from the bonds of food molecules
Photosynthesis
process by which organisms use light energy to produce ATP and other organic molecules from inorganic molecules
Heterotroph
organism that cannot make its own food
Autotroph
Organism that obtains energy from sunlight or chemicals
Choanocyte
unique flagellated cell surrounded by a collar of microvilli found inside sponges
Amoebocyte
amoeba-like cell that supplies nutrition and removes wastes form sponge body cells
Ectoderm
in animals, the outer layer of embryonic tissue from which the skin and nervous system develop
Mesoderm
middle layer of embryonic tissue in animals from which the skeleton and muscles develop
Endoderm
in animals, inner layer of embryonic tissue from which the digestive organs develop
Radial symmetry
arrangement of body parts around a central point
Cnidocyte
stinging cell used by cnidarians to stun prey
Nematocyst
barbed harpoon within a cnidocyte of a cnidarian, used to spear prey
Medusa
free-swimming, bell-shaped, mouth-down body plan of a cnidarian; jellyfish
Polyp
in cnidarians, a cylindrical, pipe-shaped animal usually attached to a rock
A symmetry
lacking symmetry
Intracellular digestion
food is digested inside the cell
Extra cellular digestion
food is digested outside the cell
Cell recognition
interaction between cells that is possibly dependent upon specific adhesion
Neuron
cell of nervous tissue that transmits a nerve impulse
Nerve net
a type of simple nervous system that is found in members of the phylum cnidaria
Gastrovascular cavity
digestive cavity with a single opening that functions as both mouth and anus
Budding
a way to a sexual reproduce where a small part of the parent's body grows into a new individual
Hermaphrodite (monocots)
organism that produces both eggs and sperm
Dioecious
having unisexual reproductive units
Gem mule
food-filled buds producing by freshwater sponges in cold or dry weather
External fertilization
union of egg and sperm occulting outside the body of either parent
Hydrostatic Skelton
a structure found in many soft-bodied invertebrates consisting of a fluid-filled cavity, the coelom, surrounded by muscles
Spongin
flexible structural protein fibers in the mesenchyme of some sponges
Spicules
needle of silica or calcium carbonate in the skeleton of some sponges
Mesoglea
the clear, inert, jellylike substance that makes up most of the bodies of jellyfish, comb jellies and certain primitive sea creatures in the phylum cnidaria
Pseudocoelom
a body cavity located between the endoderm and the mesoderm
Acoelom
animal that lakes a coelom or body cavity
Coelom
fluid- filled body cavity that forms within the mesoderm
cephalization
process of head development in bilaterally symmetric animals
Anterior
Front end of bilaterally symmetric animal
Posterior
back end of a bilaterally symmetric animal
Dorsal
top surface of a bilaterally symmetrical animal
Ventral
bottom surface of a bilaterally symmetrical animal
Endoskeleton
an internal skeleton
Exoskeleton
hard external covering of some invertebrates
Open circulatory system
system in which blood leaks out of bloods vessels and bathes the body's tissues
Closed circulatory system
system in which the blood does not leave the blood vessels and materials pass in and out by diffusing across the walls of the vessels
Bilateral symmetry
animal configuration with left and right halves that mirror each other
Gill
of fishes, structure located in the pharynx that is the site of gas exchange
Larvae
independent, immature stages in animal development that emerges from an egg
Mantle
heavy fold of tissue that surrounds the visceral mass of mollusks
Radial
rasping tongue-like organ of mollusks used in obtaining food
Visceral mass
central section of a mollusk that contains the body's organs
Ganglion
a tissue mass, which is composed mainly of somata and dendritic structures, which often interconnect with each other to form a complex system of ganglia known as a plexus.
Flame cell
specialized excretory cell found in the Platyhelminthes function like a kidney, removing waste materials
Nephridia
tiny tube-like structures
Crop
plant cultivated for use by humans
Gizzard
a portion of the digestive tube of earthworms where strong muscles grind up the organic material in ingested soil
Adductor muscle
Attachment between the two valves of a mollusk that cause the shell to open and close
Mantle cavity
space between the mantle and the visceral mass of mollusks
Segmentation
the division of some metazoan bodies and plant body plans into a series of semi-repetitive segments
Cephalothorax
the mid-body region in arthropods; consists of a head fused with a thorax
Ecdysis (molting)
process of shedding and discarding the exoskeleton; also called molting
Malpighian tubules
Slander, fingerlike organ of excretion that opens into the gut of certain arthropods
Mandibles
arthropod with jaws
Metamorphosis
process of changing through which an immature organism passes as it grows to adulthood
Nymph
juvenile stage of some insects that is a smaller version of the adult
Alveolus
Microscopic air sac in the lung where oxygen and carbon dioxide are exchanged
Amnion
membrane enclosing the embryo
Amnionic egg
watertight, fluid-filled egg in birds, reptiles, and mammals
Atrium
a chamber that receives blood returning to the heart
Cartiledge
lightweight, strong, and flexible connective tissue
Chorion
outer membrane surrounding embryos of birds, reptiles, and mammals that contributes to the development of placenta
Ectothermic
referring to an animal whose body temperature is determined by the temperature of the environment
Endothermic
refers to an animal that generates its own body heat
Internal fertilization
fertilization that occurs within the body of the female parent
Lung
sponge like respiratory organ of a vertebrate that enables gas exchange between the air and the blood
Nephron
tube-like structure in the kidneys that filters wastes from the body and retains useful molecules
Oviparous
term that describes organisms that produce eggs that hatch outside the mother’s body
Ovoviviparous
term that describes organisms that produce eggs that hatch inside the mother's body
Placenta
organ that nourishes the embryos of placental animals
Septum
thick wall that divides the atrium or ventrical vertically into right and left halves
Swim (air) bladder
the gas- of fat-filed sac of bony fishes that provides it with nutrients
Ventricle
thick-walled heart chamber that pumps blood from the heart
Atrium
a chamber that receives blood returning to the heart
Viviparous
term used to describe organisms whose young are born alive from egg cells that develop within the mother's body
Genus
taxonomic category containing similar species
Taxonomy
science of naming and classifying organisms
Binomial nomenclature
a system for giving each organism a two-word scientific name that consists of the genus followed by the species
Scientific name
unique two-word name for a species in taxonomy; the first word is the genus, the second word is the species
Family
taxonomic category containing genera with similar properties
Order
taxonomic category consisting of families with similar characteristics
Class
taxonomic category containing orders with common characteristics
Phylum
a taxonomic category containing classes with similar characteristics
Kingdom
taxonomic category that contains phyla with similar characteristics
division/domain
in taxonomy, an alternative term for phylum
Species
group of organisms that look alike and are capable of producing fertile offspring in nature
Nucleotide
subunit of nucleic acids consisting of nitrogenous base, a sugar, and a phosphate group
Deoxyribose
Five carbon sugar that is a component of DNA nucleotides
Adenine
a purine base; component of nucleotides
Guanine
nitrogen base of the purine class; component of DNA and RNA nucleotides
Thymine
nitrogenous base of the pyrimidine class; component of DNA
Cytosine
nitrogenous base of the pyrimidine class; component of RNA and DNA
Purine
class of organic, nitrogenous molecules in nucleic acids that have a double ring of carbon and nitrogen
Pyrimidine
class of organic, nitrogenous molecules in nucleic acids that have a single ring of carbon and nitrogen
Base pairing rule
Chargaff's rules that state the amount of adenine equals the amount of thymine and the amount of guanine equals the amount of cytosine
Double helix
spiral-staircase structure characteristic of the DNA molecule
Complimentary
characteristic of nucleic acids in which the sequence of bases on one strand determines the sequence of bases on the other
Replication
process of synthesizing a new strand of DNA
Helicase
enzyme that unwinds a DNA molecule's double helix before replication
Replication fork
point at which the double helix of DNA separates so that it can be copied
DNA polymerase
enzyme that catalyzes the replication of DNA
Ribonucleic acid
a type of nucleic acid that participates in the expression of genes
Gene expression
two stage processing of information from DNA to proteins
Transcription
stage of gene expression in which the information in DNA is transferred to mRNA
Translation
stage of gene expression in which the information in mRNA is used to make a protein
RNA polymerase
enzyme that carries out transcription
Promoter
specific sequence of DNA that acts as a "start" signal for transcription
Terminator
sequence of bases that tells RNA polymerase to stop transcription
Messenger RNA
RNA copy of a gene used as a blueprint for the making of a protein during translation
Transfer RNA
interpreter molecule that translates mRNA sequences into amino acid sequences
Ribosomal RNA
type of RNA molecule that plays a structural role in ribosomes
Codon
a three-nucleotide sequence in DNA or RNA that encodes an amino acid or signifies a stop signal
Genetic code
sequence of nucleotides that specifies the amino acid sequence of a protein
Anticodon
a three-nucleotide sequence on tRNA that recognizes a codon on mRNA
Gene
section of chromosome that codes for a protein or RNA molecule
Chromosome
cellular structure on which genes are located
Chromatid
one of a pair of strands of DNA that make up a chromosome during meiosis or mitosis
Centromere
region joining two chomatids
Homologous chromosome
chromosomes that are similar in shape, size, and the genes they carry
Diploid
term used to indicate cell contain two homologues of each chromosome
Haploid
having only one set of chromosomes
Autosome
a chromosome that is not directly involved in determining sex
Sex chromosome
chromosomes that differ between males and females
Genetics
study of heredity
True breeding
displaying only one form of a particular trait in offspring
P generation
plants that displayed only one form of a particular trait
F1 generation
the offspring from a cross of two varieties
F2 generation
the offspring from crosses among individuals of the F1 generation
Dominant
trait tat is expressed when its allele is homozygous or heterozygous
Recessive
the trait that is not expressed in F! generation after crossing
Homozygous
refers to a pair of genes, or an individual, with two identical alleles for a trait
Heterozygous
refers to a pair of genes, of an individual, with two different alleles for a trait
Allele
an alternative form of a gene
Phenotype
observable characteristics of an organism
Genotype
genetic constitution of an organism as indicated by its set of alleles
Law of segregation
law stating that pairs of genes separate in meiosis and each gamete receives one gene of a pair
Law of independent assortment
law stating that pairs of genes separate independently of one another in meiosis
Cell cycle
repeating five-phase sequence of eukaryotic cell growth and division
Mitosis
process in which the nucleus of a cell divides into two nuclei, each with the same number and kind of chromosomes
Cytokinesis
division of the cytoplasm
Interphase
period of growth between two mitotic or meiotic divisions of a eukaryotic cell
Spindle fiber
network of hollow protein cables that form between separated centrioles and move chromosomes apart
Centromere
region joining two chrinatids
Meiosis
process in which the nucleus of a cell completes two successive divisions that produce four nuclei, each with a chromosome number that has been reduced by half
Crossing over
the exchange of reciprocal segments of DNA by chromosomes at the beginning of meiosis; source of genetic recombination
Reduction division
in meiosis, term used to indicate the reduction of the number of chromosomes
Genetic recombination
rearrangement of genetic material
Probability
the likelihood that a specific event will occur
Hybrid
offspring of individuals from two different species
Monohybrid cross
cross involving one pair of contrasting traits
Punnett square
diagram used by biologist to predict the probable outcome of a cross
Dihybrid crosses
a cross that involves two pairs of contrasting traits
Incomplete dominance
condition in which a trait is intermediate between two parents
codominance
condition in which both alleles for a gene are expressed when present
Multiple alleles
having more then two alleles (versions of the gene) for a genetic trait
continuous variation
a genetic phenomenon in which a trait is controlled by several genes and therefore exhibits a variety of phenotypes
Gamete
haploid cell that participates in fertilization by fusing with another haploid cell
Zygote
Fertilized Egg cell
Trisomy
condition in which a diploid cell has an extra chromosome
karyotype
array of the chromosomes found in an individual's cells arranged in order of size and shape
Down syndrome
a syndrome of congenital defects, especially mental retardation, resulting from an additional copy of chromosomes
Nondisjuction
accident in chromosome separation when one daughter cell receives both chromosomes and the other daughter cell receives none
Amniocentesis
procedure in which a sample of amniotic fluid is withdrawn and tested for genetic abnotmalities in a fetus
Chorionic villi sampling
fetal-testing procedure in which pieces of the chorinic villi in a mother's uterus are removed and examined for genetic abnormalities
Mutation
change in the DNA of a gene or chromosome
Deletion
mutation in which a nucleotise or segment of DNA is lost
Duplication
form of mutation in which a chromosome contain an extra copy of a segment of DNA
Inversion
mutation in which a chromosome fragment rejoins its original chromosome with its nucleotides reversed
translocation
form of mutation caused by a chromosome fragment joining a nonhomologous chromosome during cell division
Sex-linked trait
a trait that is determined by a gene found on the X chromosome
Pedigree
family history of traits recorded over generations
Population
group of individuals that belong to the same species, live in the same area, and breed with others in the group
Natural selection
process by which population change in response to their environment as individuals better adapted to the environment leave more offspring
Adaptation
process of becoming adapted to an environments; an anatomical structure, physiological process, o behavioral trait that improves an organism's likelihood of survival and reproduction
Microevolution
change that occurs within a species over time
Isolation
condition in which two populations of a species are separated so that they cannot interbreed
Macroevolution
change that occurs among species over time as new species evolve and old species become extinct
Paleontology
Common ancestor
species from which two or more species diverged
Homologous structure
structures that share a common ancestry
Vestigial structure
structure reduced in size and function; considered to be evidence of an organism’s evolutionary past
Gradualism
model of evolution in which gradual change over a long period of time leads to macroevoltion
Punctuated equililbrium
model of evolution in which short period of rapid change in species are separated by long periods of little or no change
Divergence
accumulation of differences between groups; can lead to the formation of new species
Hardy-Weinberg Principle
principle stating that the frequency of alleles in a population does not change unless evolutionary forces such as selection act on the population
Allele frequency
the relative abundance of an allele of a gene within a population, expressed as a percentage
Gene flow
movement of alleles into or out of a population due to the migration of individuals to or from the population
Non-random mating
mating between individuals of the same genotype
Genetic drift
random change in allele frequency in a population