at which of the following stages do human skin cell nuclei have the same DNA content
g1 and late mitotic telophase
each chromosome consists of a pair of attached chromatids in a cell at
mitotic phase, meiotic prophase 2,meiotic prophase 1, and meiotic anaphase 1.
in an animal cell at meiotic metaphase, you would expect to find
a pair of centrioles within each microtubule organizing center
in the spindle, the ________ ends of kinetochore microtubules are embedded in the kinetochore, and the ______ ends are at the spindle pole.
a particular plant species has a diploid chromosome number of 20. a haploid cell of that species at mitotic prophase contains a total of how many chromosomes and chromatids?
a diploid nucleus at early mitotic prophase has_____ set(S) of chromosomes; a diploid nucleus at mitotic telophase has ____ set(s) of chromosomes
the life cycle of a sexually reproducing organism includes
mitosis, meiosis, and fusion of sex cells
the reason mendel discovered the basic principle of inheritance is that he
began by establishing true-breeding lines
one of the autosomal loci controlling eye color in fruit flies has two alles, one for brown and the other for red. fruit flies from a true breeding line with brown eyes were crossed with flies from a true breeding line with red eyes.the
f1 flies had red eyes. what conclusions can be drawn from this experiment?
The Allele for red eyes is dominant over the allele for brown
the F1 flies were mated with brown eyed flies from a true breeding line. what phenotypes would you expect the offspring to have?
half red and half brown eyes
individuals of genotype AaBb were crossed with aabb. approximately equal numbers of the following classes of offspring were produced: AaBb Aabb, aaBb, and aabb. these results illustrate mendels principles
independent assortment and segregation
when homozygous, a particular allele of a locus in rats causes abnormalities in the cartilage throughout the body, an enlarged heart, slow development, and death. this is an example of
in peas yellow seed color is dominant to green. determine the phenotypes (and their proportions) of the offspring of the following crosses. A) homozygous yellow green,B) heterozygous yellow green,C) heterozygous yellow homozygous yellow,D) hetero yellow hetero yellow.
A. all yellow
B. 1/2 yellow 1/2 green
D. 3/4 yellow 1/4 green
if two animals heterozygous for aa single pair of alleles are mated and have 200 offspring, about how many would be expected to have the phenotype of the dominate allele (that is to look like the parents)
when two long winged flies were mated, the offspring included 77 with long wings and 24 with short wings. is the short winged condition dominant or recessive? what are the genotypes of the parents.
short winged condition is recessive, both parents are heterozygous.
outline a breeding proceedure where by a true breed strain of red cattle could be established from a roan bull and a white cow
repeating matings of the roan bull and the white cow will yeild an approximate 1:1 ratio of roan to white offspring repeating matings among roan offspring will yeild red, roan, and white in approximated 1:2:1 ratio. the mating of two red individuals will yeild only red offspring.
what is the probability of rolling a seven with a pair of dice? which is a more likely outcome, rolling a six or eight?
there are 36 possible outcomes when a pair of dice are rolled.there are six ways of obtaining a seven, five ways of rolling a six, and five of rolling an eight.
In rabbits, spotted coats (S) is dominant to solid color(s) and black(B) is dominant to brown(b). these loci are not linked. a brown, spotted rabbit from a pure line is mated to a solid black, also from a pure line. what are the genotypes of the parents? what would be the genotype and phenotype of an f1 rabbit? what would be the expected geno and phenotypes of the f2 generation?
the genotype of the brown spotted rabbit is bbSS. the genotype of the black solid rabbit is BBss. an f1 rabbit would be black,spotted BbSs. the f2 is expected to be 9/16 black, spotted B_S_ ,3/16 black, solid B_ss, 3/16 brown,spotted bbS_, and 1/16 brown,solid bbss.
mr and mrs smith are concerned because thier own blood types are A and B, respectively, but thier son richard is blood type O. could richard be the child of these parents?
the expression of an allele called frizzle and fowl causes abnormalities of the feathers. as a consequence, the animals body temp is lowered, adversly affecting many functions of the internal organs. when one gene affects the traits of an organism, we say that gene is...
when griffith injected mice with a combination of live rough-strain and heat-killed smooth-strain pneumocci, he discovered that
the dead mice contained living smooth-strain bacteria.
which of the following inspired avery and his coleges to perform the experiments demonstating that the transforming principle in bacteria is dna?
griffiths experiment on smooth and rough strains of pneumocci
in the Hershey-Chase experiment with bacteriophages
viral dna was shown to enter bacterial cells and cause the production of new viruses within the bacteria
the 2 complementary strand of the dna double helix are held to one another by..
hydrogen bond between nucleotide basis
if a segment of dna is 5'-CATTAC-3', the complementary dna strand is...
the experiments in which Meselson and Stahl grew bacteria in heavy nitrogen conclusivelsy demonstrated that dna...
replicated semi conservitively
the staement "dna replicates by a semi conservitive mechanism" means that...
each double helix consists of one old and one newly senthsized strand.
which of the following depicts a relative arrangement of the complementary strands of a dna double helix?
3'-5' 3'-3' 3'-5' 3'-3' 5'-5' 5'-3'
the immediate source of energy for dna replication is
the hydrolosis of necleotides with 3 phosphate groups