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the process in cell division during which the number of chromosomes decreases to half the original number by two divisions of the nucleus, which results in this production of sex cells
a haploid reproductive cell that unites with another haploid reproductive cell to form a zygote
an organism's appearance or other detectable characteristics that results from the organism's genotype and the environment
the sex chromosome that is present in both sexes: singly in males and doubly in females
the entire genetic makeup of an organism; the combination of genes for one or more specific traits
in biology, the offspring of a cross between parents that have differing traits; a cross between individuals of the same species, subspecies, or varieties
in biology, an individual who has one copy of a recessive autosomal allele that causes disease in the homozygous condition
the science of heredity and of the mechanisms by which traits are passed from parent to offspring
in genetics, describes an allele that is expressed only when no dominant allele is present in an individual
the likelihood that a possible future event will occur in any give instance of the event; the mathematical ratio of the number of times one outcome of any is likely to occur to the number of possible outcomes of the event
a condition in which a trait in an individual is intermediate between the phenotype of the individual's two parents because the dominant allele is unable to express itself fully
describes an individual that has identical alleles for a trait on both homologous chromosomes
the most basic physical unit of heredity; a segment of nucleic acids that codes for a functional unit of RNA and/or protein
in genetics, describes an allele that is fully expressed whenever the allele is present in an individual
the failure of homologous chromosomes to separate during meiosis 1 or the failure of sister chromatids to separate during mitosis or meiosis 2
an association between genes in sex chromosomes that makes some characteristics appear more frequently in one sex than in the other
the process of becoming adapted to an environment;; an anatomical, physiological, or behavioral change that improves a population's ability to survive
the human practice of breeding animals or plants that have certain desired traits
the process by which individuals that are better adapted to their environment survive and reproduce more successfully than less well adapted individuals do; a theory to explain the mechanism of evolution
describes a character that is shared by a group of species because it is inherited from a common ancestor
Jean Baptiste Lamarck
This man developed the first cohesive theory of evolution after his studies of biology
Characteristics of an organism gained during its lifetime, not determined genetically and therefore not transmitted to the offspring
these mechanisms prevent mating between individuals of different species OR they prevent fertilization from occuring if mating does take place
Classification system in which each species is assigned a two-part scientific name
Linnaeus and classification
in this system of classification, organisms are grouped at successive levels of a hierarchy based on similarities in their form and structure
Lucy; "southern" ape, 3.2 MYA, brain capacity: 515cc, found in Afar Valley, petite type
extinct species of upright east African hominid having some advanced humanlike characteristics
A species of the creatures Hominid who have larger brains and to which humans belong, dependent of language and usage of tools.
(plate tectonics) a hypothetical continent including all the landmass of the earth prior to the Triassic period when it split into Laurasia and Gondwanaland
Place where a lot of info was found. info, such as the finches who had different beaks, but were thought to be of the same ancestor
an animal phylum that has a notochord, a dorsal hollow nerve cord, and gill slits at some time in its life cycle
vertebrates that live in water and on land, smooth skin covers body, lay eggs, cold blooded
warm-blooded vertebrate animals characterized by hair on the skin and, in females, mammary glands for nourishing the young
any of various mostly cold-blooded aquatic vertebrates usually having scales and breathing through gills
radially symmetrical marine invertebrates including e.g. starfish and sea urchins and sea cucumbers
Two-cell layered body with a digestive cavity surrounded by tentacles that sting prey. E.g. jellyfish, hydras, sea anemones.
A group of organisms that have jointed appendages, an exoskeleton, bilateral symmetry, and reproduce sexually; insects, arachnids, millipedes and cenitpedes, and crustaceans
the female reproductive part of a flower that produces seeds and consists of an ovary, style, and a stigma
in plants, a flower structure that contains one or more ovules from which female gametophytes are produced; in animals, the female gonad that produces eggs
the male reproductive structure of a flower that produces pollen and consists of an anther at the tip of the filament
the process by which plants, algae, and some bacteria use sunlight, carbon dioxide, and water t produce carbohydrates and oxygen
the reproductive structure of a flowering plant that usually consists of a pistil, stamens, petals, and sepals
the inner germ layer that develops into the lining of the digestive and respiratory systems
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