Studied by 48 peoplerah rah rah sis boom bah hit em in the head with a kielbasa
asexual reproduction
a mode of reproduction where offspring arise from a single organism, inheriting genes from that parent only
autosomes
chromosomes that are not sex chromosomes, humans have 22 pairs
binary fission
a type of sexual reproduction in prokaryotes where a cell divides into 2 genetically identical cells
cancer
the uncontrolled growth of a cell
centromere
the region of a chromosome where the 2 sister chromatids attach
crossing-over
the exchange of genetic material between homologous chromosomes during meiosis I
cytokinesis
the division of the cytoplasm to form 2 separate daughter cells after mitosis or meiosis
diploid
a cell that contains 2 complete sets of chromosomes (2n), one from each parent
fertilization
the process of a sperm cell joining with an ovum to form a zygote
gametes
sex cells that are haploid
gene
a segment of DNA that codes for a protein or RNA molecule
haploid
a cell that contains only one set of chromosomes
homologous chromosomes
Chromosomes that are similar in size shape and genetic content
independent assortment
the random distribution of homologous chromosomes during meiosis
karyotype
a picture of all the chromosomes in a cell arranged in pairs
meiosis
a type of cell division that reduces the chromosome number by half, creating 4 haploid cells
oogenesis
the process by which ova are produced by the female
ovum
female gamete
sex chromosomes
chromosomes that determine the sex of an individual
sperm
the male gamete
spermatogenesis
the process by which the male produces sperm
spindle
a structure composed of microtubules that segregates chromosomes into the daughter cells during mitosis and meiosis
zygote
a fertilized egg cell formed by the union of a sperm and an ovum
Alleles
different forms of a gene that can live in a different location
co-dominance
a situation in which both animals contribute equally and visibly to the phenotype
complete dominance
a relationship in which one allele is completely dominant over another
dominant allele
an allele that masks the presence of a recessive allele in the phenotype
gregor mendel
father of genetics, known for his work on the pea plants and establishing the principles of genetics
genotype
the genetic makeup of an organism
heredity
the passing of traits from parents to offspring
heterozygous
having 2 different alleles for a particular gene
homozygous
having 2 identical alleles for a particular gene
incomplete dominance
a situation in which the phenotype of the heterozygotes is intermediate between between the phenotypes of individuals homozygous for either allele
multiple alleles
a situation in which a gene has more than 2 alleles
phenotype
the physical expression of a genotype
polygenic inheritance
an additive effect of 2 or more genes on a single phenotypic character
punnet square
a diagram used to predict the genotype and phenotype combinations of a genetic cross
recessive allele
an allele that is masked by the presence of a dominant allele
sex-linked traits
traits that are determined by genes located on the sex chromosomes
anti-codon
a 3 nucleotide sequence on the tRNA that pairs with the complementary codon on mRNA during translation
codon
a 3 nucleotide sequence on tRNA that specifies a particular amino acid
DNA helicase
an enzyme that unwinds the DNA double helix during DNA replication
DNA polymerase
an enzyme that synthesizes new DNA strands using a template strand
Hydrogen bonds
weak bonds that hold the 2 strands of DNA together between complementary bases
nucleotide
the building block of DNA and RNA, consisting of a sugar, a phosphate group, and a nitrogenius base
replication fork
the Y-shaped region where the DNA is split into 2 strands and being replicated
RNA polymerase
An enzyme that synthesizes RNA from a DNA template during transcription
transcription
The process of copying a segment of DNA into RNA
translation
The process by which mRNA is decoded and a protein is produced
Adaptation
A trait that increases an organisms fitness in its environment
Darwin
created the theory of natural selection
Divergence
The accumulation of differences between groups which can lead to the formation of new species
gradualism
the theory that evolution occurs slowly but steadily
homologous structures
features that share common ancestry
Lamarck
use/disuse
Lyell
geologist
natural selection
survival of the fittest
paleontologist
scientist who studies fossils
punctuated equilibrium
the theory that species evolve through short periods of rapid change
reproductive isolation
when species cant interbreed
speciation
formation of a new species
vestigial structures
structures of little use
wallace
evolution by natural selection
population
a group of the same species living in the same area
exponential growth
a growth pattern that proceeds rapidly
logisical growth
a slow but long period of growth
carrying capacity
the maximum population size that a environment can sustain
directional selection
a type of natural selection that favors individuals with extreme variation of a trait
stabilizing selection
a type of natural selection that favors average individuals
non-random mating
species choosing who they mate with
genetic drift
random changes in allele frequencies
gene flow
alleles flowing in and out of a population
Note
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