exam 4 flashcards
Traits that are controlled by genes located on the X chromosome are said to be __________.
sex linked
In Mendel’s experiments on seed color in pea plants, when a dominant yellow seed-bearing plant was crossed with a recessive green seed-bearing plant, what was the approximate phenotypic ratio among the F2 generation?
3 yellow: 1 green
Structures that have no apparent function but had a function in ancestral species are
vestigial structures
Select which blood type could be safely given to anyone
O
ABO blood group determination is an example of
multiple alleles
Which offspring inherit all their mitochondrial DNA from their mother and none from their father?
Both sons and daughters
The observation that different geographical areas sometimes exhibit plant and animal communities of similar appearance, even though the individual plants and animals are not closely related, is called
convergent evolution
Alternate forms of the same gene are called
alleles
The allelic make up of a cell or individual is referred to as its
genotype
When viewing a human pedigree for a particular genetic condition, you observe that affected individuals appear in some generations, but not in others. This suggests the condition is ___________.
recessive
Let R = red pigment and r = no pigment (white). In carnations, RR offspring make a lot of red pigment, rr offspring make no pigment and Rr offspring make a small amount of red pigment, thus appearing pink. Pink carnations are therefore an example of
incomplete dominance
If an individual allele has more than one effect on the phenotype, this is called
pleiotropy
An allele for a particular trait that is only expressed in the presence of a second copy of the same allele is called
recessive
Let P = purple flowers and p = white, and T = tall plants and t = short. What are the genotypes of the gametes that are produced by a plant that is heterozygous for both traits?
PT, Pt, pT, and pt
Which observations illustrate shared ancestry by anatomical comparison studies? (check 3)
a. Structures are found to be homologous
b. Different structures evolve in similar ways when subjected to the same selective pressures
c. The same structure has evolved to carry out different functions’
d. A structure becomes vestigial
a, c, d
Eukaryotic cells acquired mitochondria and chloroplasts by
endosymbiosis
The first detailed and quantitative studies on inheritance were carried out by an Austrian monk named __________.
Mendel
Small RNAs can regulate gene expression. One type, called micro RNA (miRNA), acts by binding directly to
mRNA to prevent translation
The shape of the beaks of Darwin’s finches and industrial melanism are often cited as examples of the process of _______ _______ leading to evolutionary change.
natural selection
The group that probably gave rise to chloroplasts is the
cyanobacteria