bio unit 3 vocab Flashcards
chart that shows relationships within a family
pedigree
genetic make-up of an organism
genotype
appearance of a trait in organisms
phenotype
used to predict possible offspring in a cross
Punnett square
having same alleles for a trait
homozygous
have two different alleles for a trait
heterozygous
autosomal recessive disorder that causes the red blood cells to have an abnormal hemoglobin causing an abnormal shape
Sickle Cell Anemia
both alleles in the heterozygote are partially expressed
incomplete dominance
tetrad formation and exchange of genetic material in the chromatids
Crossing Over
during gamete formation, the alleles of different genes segregate independently of one another, meaning that the inheritance of one trait does not influence the inheritance of another trait.
Law of Independent assortment
chromosome pairs 1-22
autosome
a photograph of metaphase chromosomes grouped in pairs
karyotype
error in meiosis in which chromosomes fail to separate
nondisjunction
one homologous chromosome is missing
monosomy
cross involving one trait (a cross involving organisms that are heterozygous for one trait) Aa X Aa
monohybrid cross
cross involving two traits (a cross involving organisms that are heterozygous for two traits) AaBb X AaBb
dihybrid cross
alternate form of the same trait/gene
allele
both alleles in the heterozygote are fully expressed
codominance
genes that have more than two alleles for a trait
multiple alleles
2n, two complete sets of chromosomes
Diploid
a diploid body cell for growth and repair made by the process of mitosis
somatic cell
occurs in Prophase I of Meiosis I where nonsister chromatids exchange genetic material - bring about genetic variation in gametes
crossing over
The chromosome number is reduced from diploid to haploid (34->17) in meiosis
chromosome number reduction
Homologous pairs of chromosomes orient randomly at metaphase I of meiosis
independent assortment of chromosomes
There will be greater genetic variation in the gametes resulting from meiosis due to crossing over, independent assortment and reduction in chromosome number
genetic variation in meiosis
a trait that is determined by more than one gene
Polygenic Trait gamete
a cell with half a set of chromosomes represented by “n”
haploid
disease caused by defective gene on autosome
autosomal disease
disease caused by the defective gene on sex chromosome
sex - linked disease
during gamete production, alleles for a gene separate
law of segregation
The pollen from one plant fertilizes the ova from a different plant
Cross-fertilization
The pollen from one plant fertilizes the ova from the same plant
Self-fertilization
part of chromosome breaks and attaches to another
translocation
a cell with full set of chromosomes represented by “2n”
diploid
