Test 1 Flashcards
(26 cards)
______ are the genetic units of inheritance; each can exist in multiple different forms called ____
genes; alleles
____ different alleles are possible for any given gene; a human individual may have a maximum of ____ different alleles for any given gene
Many; two
Chromosomes in metaphase of Meiosis 2 closely resemble
chromosomes in metaphase of mitosis
How many different gametes can a tetrahybrid (AaBbCcDd) produce
2^4 aka 16
Sex determination in the animal kingdom
the sex determining chromosomes in humans is the Y chromosome
If there are 25 RR, 50 Rr, and 0 rr, that means
r is a lethal allele
environmental influence and tail length
2 parabola graph
cell is diploid with 6 chromosomes
6 skinny rectangles with one small dot in each
How do mammals account for the dosage of genes found on the X chromosome between males and females
Females randomly turn off an X chromosome, so their body is a mosaic of somatic cells that express either the maternal or paternal X chromosome
The PAT locus is paternally imprinted. PAT+ is normal, PAT- causes neurodegenerative disease. If an affected man has PAT+PAT- which allele is expressed and which parent did he inherit it from
PAT-, his mother
A recessive allele on the X chromosome causes color deficiency, A color deficient boy has a mom with normal vision and a color deficient father. which parent did he get the color deficient gene from
mother
Consider a cross between a true breeding plant with white flowers and a true breed plant with red flowers. if the progeny has white flowers with red spots or red flowers with then spots then
codominance
B brown fur, b white fur
Heterozygous brown fur is Bb and true breeding white fur is bb so F1 generation has half Bb and half bb. If 2 brown mice from F1 were crossed (Bb and Bb), then there would be 3 brown and 1 white
Mendels First Law
2 copies of alleles separate from each other during transmission from parent to offspring. Bb and Bb separated to form offspring which led to 3 brown and 1 white
A true breeding melon plant with tan seeds crossed with true breeding plant that produced red seeds
Red is dominant since F1 had all red seeds.
what is the probability of getting genotype AABbCc from AaBbCc x AaBBCc
1/4x1/2x1/2=1/16 percent
Inheritance patterns
Autosomal recessive skips generations
probability of having 6 children all boys
1/2 x 1/2 6 times = 1/64
Mitochondrial DNA follows a maternal pattern because
DNA from the mom gets passed down and the DNA from the dad always gets killed. we are still not exactly sure as to why.
Maternal inheritance
always passes down the disease to all her kids
Girl with. type B blood whose father has type O blood. What are the genotypes of their children
I^B I^AB
Phenotypes and ratio
type B, type AB, 1:2:1
What phenomenon accounts for the observed distribution of phenotypes in the progeny
Genes A, B, and D are loosely linked / on same chromosome but far apart
DCO and parental genotypes tells us
the order of genes/ what gene is in the middle
