39 terms

6.1, 6.2, 6.3, 6.4, 6.5 Vocabulary CP

STUDY
PLAY

Terms in this set (...)

somatic cells
a.k.a. body cells; any cell in the body that is not a gamete
gametes
sex cells
homologous chromosomes
chromosomes that have the same sequence of genes and same structure; they pair up during meiosis
autosome
any chromosome that is not a sex chromosome (in humans, the first 22 pairs)
sex chromosome
one pair of chromosomes that determines the sex of an individual (in humans, the 23rd pair)
sexual reproduction
reproduction in which gametes from two parents unite to produce offspring
fertilization
the union of male and female gametes to form a zygote
zygote
the diploid cell that is the result of fertilization
diploid
describes a cell contains two copies of each chromosome (2n)
haploid
a cell contains one copy of each chromosome (n)
meiosis
a process in cell division in which the number of chromosomes decreases to half the original number
crossing over
the exchange of chromosome segments between homologous chromosomes (during prophase I of meiosis I)
meiosis I
process that divides homologous chromosomes, producing two haploid cells with duplicated chromosomes
meiosis II
process that divides sister chromatids, and results in undoubled chromosomes
gametogenesis
process by which gametes are produced through the combination of meiosis and other maturational changes
sperm
male gamete
egg
female gamete
polar bodies
created during meiosis in females - contain little DNA and eventually disintegrate
metaphase I
chromosomes line up in homologous pairs - this is the main difference in the processes of meiosis and mitosis
traits
a recognizable feature or characteristic of an organism
genetics
the study of biological inheritance patterns and variation in organisms
purebred
type of organism whose ancestors are genetically uniform
cross
mating of two organisms
law of segregation
Organisms inherit two copies of each gene, one from each parent
Organisms donate only one copy of each gene in their gametes. The two copies of each gene segregate, or separate, during gamete formation (meiosis)
gene
one segment of DNA that has the code for one protein (trait)
allele
one of the alternative forms of a gene
homozygous
having the same allele for one gene
heterozygous
having two different alleles for one gene
genome
all of the genetic material in an organism or species
genotype
the genetic makeup for a gene or set of genes
phenotype
an organism's appearance or characteristic (that results from the genotype)
dominant
an allele that is expressed regardless of the other allele
recessive
an allele that is expressed only when two copies are present
Punnett square
a grid system for predicting all possible genotypes resulting from a cross
testcross
cross between an organism with an unknown genotype and an organism with the recessive phenotype
law of independent assortment
allele pairs separate independently of one another during gamete formation
dihybrid cross
a cross involving the inheritance of two different traits
probability
the likelihood that a particular event will occur
monohybrid cross
a cross involving the inheritance of one trait