Unit 7 Genetics Review Sheet Vocab

Front 1

allele

Back 1

one of a number of different forms of the same gene for a specific trait

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carrier

Back 2

a girl who is heterozygous for a trait; she has the allele in her cells and can pass it on to her kids, but she doesn't display the trait herself

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clone

Back 3

large population of genetically identical cells derive from one original cell

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dihybrid cross

Back 4

a cross in which two pairs of traits are studied

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diploid

Back 5

description of a cell that contains a double set of chromosomes, one from each parent

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dominant

Back 6

form of a gene that is expressed even if present with a contrasting recessive allele

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egg

Back 7

female gamete

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exon

Back 8

expressed DNA

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fertilization

Back 9

The penetration of the egg by the sperm and fusion of genetic materials to result in the development of an embryo

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fetus

Back 10

unborn young of an animal during the later stages of development; in humans, the name given to embryos after eight weeks of development

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gamete

Back 11

specialized reproductive cell involved in sexual reproduction

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genetics

Back 12

branch of biology that studies heredity

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genotype

Back 13

genetic makeup of an organism

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haploid

Back 14

containing a single set of chromosomes

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heredity

Back 15

passing of traits from parents to their young

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heterozygous

Back 16

organism that has two different alleles for the same trait; hybrid

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homologous chromosomes

Back 17

chromosomes that occur in pairs; have a corresponding structure

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homozygous

Back 18

organism that has two identical alleles for a particular trait

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Human Genome Project

Back 19

An international research effort begun in the 1980s to map and sequence all the genes found in the human species

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inbreeding

Back 20

method of maintaining desirable characteristics by crossing individuals with similar characteristics who are often closely related

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intron

Back 21

junk DNA in between segments of expressed DNA (exons)

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karyotype

Back 22

A photomicrograph of an individual's chromosomes arranged in a standard format showing the number, size, and shape of each chromosome type

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monohybrid cross

Back 23

a cross in which one pair of traits is studied

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monosomy

Back 24

having a single copy of a chromosome, rather than the usual pair

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nondisjunction

Back 25

failure of homologous chromosomes to separate normally during meiosis

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phenotype

Back 26

physical characteristics of an organism

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recessive

Back 27

description of an allele that is only expressed in the homozygous state

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recombinant DNA

Back 28

DNA molecule that forms from the combination of portions of two different DNA molecules

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selective breeding

Back 29

method of improving a species by choosing only the most desirable (for a certain trait) organisms and having them produce offspring with the desirable traits

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sexual reproduction

Back 30

process in which two cells, normally from different individuals, unite to produce the first cell of a new organism

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somatic cell

Back 31

body cell (not sex cell)

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sperm

Back 32

male gamete

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trait

Back 33

characteristic that a living thing can pass on to its young

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trisomy

Back 34

having three copies of a chromosome instead of the usual two

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zygote

Back 35

fertilized egg cell