Genetics exam 1 Flashcards
Mendel proposed that there are basic units of heredity passed from parent to offspring.
Particulate theory of inheritance
Genes come in homologous pairs that segregate from each other into gametes, half carry one member of the pair and half carry the other.
Mendel’s first law of segregation
G1- duplication, S- synthesis, G2- cell double checks for errors.
Interphase
Connects the sister chromatids together in the middle.
Centromere
Site on either side of sister chromatid where spindle fibers attach.
Kinetochore
Reach out and bind to sister chromatids to pull them apart.
Spindle fibers
Area between top and bottom of inner sister chromatids where tetrads form.
Synaptonemal complex.
The attachment site that holds homologous chromosomes together after crossing over.
Chiasmata
Kinetochores attach to microtubule from opposite spindle poles.
Mitosis and Meiosis II
Sister chromatids segregate to the same spindle pole.
Meiosis I
Segregation of sister chromatids results in-
Segregation of alleles.
Cross between two heterozygotes
Monohybrid cross
Cross between two individuals with two observed traits that are controlled by two distinct genes- from independent assortment.
Dihybrid
Cross between a heterozygote for two genes and a recessive for all genes.
Testcross
Take fraction of each individual and multiply them together to get a fraction of what the combined offspring between individuals would be.
Product rule