Final Terms Part 4 Flashcards Preview

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Flashcards in Final Terms Part 4 Deck (40)
1

sister chromatid

replica of chromosome - attached at centromere

2

homologous chromosomes

chromosomes that code for the same traits, but can be different
-one from each parent

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monohybrid cross

cross to study one trait
gave raise to law of segregation

4

dihybrid cross

cross to study two traits
gave raise to law of independent assortment

5

law of segregation

two alleles segregate from each other during the formation of the gametes in anaphase I of meiosis
half gametes have one allele, thus union of gametes is random

6

law of independent assortment

pairs of alleles for genes on different chromosomes segregate independently in the formation of gametes during meiosis

7

testcross

used to determine genotype of an organism displaying dominant phenotype by mating it with a homozygous recessive

8

codominance

gene products are equally expressed
AB blood type

9

incomplete dominance

homozygous dominant gives two gene products (ie dark red)
homozygous recessive gives no product
hets give intermediate (ie light red/pink)

10

epistatis

form of gene interactino in which one gene interferes with the expression of another gene

11

haplosufficiency

one gene product is sufficieny for life

12

x-linked

trait is found on the x chromosome

13

hemizygosity

males are hemizygous-have one x and one y

14

SRY in humans

sex-determining region
becomes active in embryo
encodes testes determining factor

15

Barr bodies

inactive X chromosome in females- used to set gene dosage

16

gene dosage

the amount of gene product expressed

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pleiotropy

one gene is responsible for multiple phenotypes

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penetrance

the % of people with the genotype that express the phenotype

19

expressivity

the range of phenotypes

20

phenotypic variation

influenced by environment
epigenetics
modifier genes

21

maternal effect

phenotype of offspring is determined by the nuclear genotype of mother

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extranuclear inheritance

typically maternal inheritance
DNA found in mitochondria and chloroplasts

23

polygenetic

many genes

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multifactorial

many environmental factors

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discrete trait

traits have clear cut phenotypes

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quantitative trait

trait with a range of phenotypes with continuous distribution

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continuous variation

lines between phenotypes vary -quantitative traits

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heritability

the degree to which traits are influenced by genetics

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quantitative trait loci

used to determine gene archecture

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genetic drift

variation in gene frequency due to founder effect or bottle necking

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bottleneck

the population size is drastically reduced

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founder effect

population is based from a small number of breeding individuals

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natural selection

natural selects for traits that are advantageous

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gene pool

the number of alleles in a population

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migration

individuals moving in and out of a population

36

gene flow

flow of alleles in or out of a population

37

selective mating

most organisms do not mate randomly
positive and negative mating

38

genomics

the study of an entire genome or genomes

39

functional genomics

global analysis of the function of sequences in a genome especially useful when considering complex traits

40

comparative genomics

comparison of entire genome from different species, individuals, or groups
-genetic variation
-evolutionary variation