genetics Flashcards
how many times does a cell go through meiosis
2 rounds
how many cells does meiosis create
4
are homologous chromosomes copies of each other
no
what is each half of a duplicated chromosome
chromatid
what holds a chromosome together
centro mere
when are homologous chromosomes divided
meiosis 1
when are sister chromatids divided
meiosis 2
when is DNA copied
before meiosis
what is the end result of meiosis
haploid cells
how many sets of chromosomes are in a diploid
two
how many sets of chromosomes are in a haploid
one
what is the production of gametes
gametogenesis
what does gametogenesis include
meiosis and changes that produce a mature cell
what is the male gamete
sperm
what is the female gamete
egg
what is the sperm’s main contribution to the embryo
DNA
when does the formation of an egg start
before birth
when does the formation of an egg end
when a sperm fertilizes it
what does an egg cell contribute to an embryo
DNA, organelles, molecular building blocks, and other material and embryo needs
how many cells actually become and egg from each round of meiosis
1
what are the other cells that don’t become an egg called
polar bodies
what are distinguishing characteristics that are inherited
traits
what is the study of biological inheritance patterns and variations in organisms
genetics
who was the Austrian monk who established much of our understanding about genetics
Gregor Mendel
if a line of plants has become self pollinated for long enough that line becomes genetically uniform or …
purebred
what is the mating of two organisms called
cross
what is Mendel’s first law
law of segregation
explain law of segregation
organisms inherit two copies of genes
organisms donate one copy of each gene in their gametes
what is a specific location on a pair of homologous chromosomes for a gene
locus
what are alternative forms of a gene that may occur at a specific locus
allele
how many alleles do humans have for each gene
two
what are two of the same alleles at a specific locus
homosygous
what are two different alleles at a specific locus
heterosygous
what is all of an organisms genetic material
genome
what refers to the genetic makeup of a specific set of genes
genotype
what refers to the physical characteristics or traits of an organism
phenotype
what type of allele is expressed when two different alleles or two dominant are present
dominant
what type of allele is expressed only when two copies are present
recesssive
who developed the the punnet square
RC Punnet
what are crosses that examine the inheritance of only one specific trait
monohybrid
what is a cross between an organism with an unknown genotype and an organisms with the recessive phenotype
testcross
what are crosses that examine the inheritance of two different traits
dihybrid
what is Mendel’s second law
law of independence
explain law of Independence
allele pairs separate independently of each other during gamete formation
what is the likelihood that a particular event will happen
probability
what is the major advantage of sexual reproduction
genetic variation
what is the exchange of chromosome segments between homologous chromosomes
crossing over
genes located together tend to be inherited together
genetic linkage
