Comb shape in chickens is determined by 2 different genes that independently assort (R/r and P/p). A walnut comb is produced with at least one "R" allele and one "P" allele. A rose comb is produced with at least one "R" allele and two "p" alleles. A pea comb is produced by two "r" alleles and at least one "P" allele. A single comb is produced when both genes are homozygous recessive. If a single comb chicken is mated with a pea comb chicken that is homozygous for the "P" allele, what phenotype(s) for comb is/are expected in their offspring?
a) Only pea comb
b) Only single comb
c) 1/2 pea comb and 1/2 single comb
d) 3/4 pea comb and 1/4 single comb
Ans: a) Only pea comb
You might also like to view...
Colonies growing on modified cefsulodin-irgasan-novobiocin (CIN) agar appear to be either Aeromonas spp. or Yersinia enterocolitica. Which test should be performed to differentiate be-tween these two organisms?
a. String test b. Sucrose fermentation c. Glucose fermentation d. Oxidase
What is false about sea stars?
a. they cannot regenerate. b. broadcast spawning is common. c. asexual reproduction is common. d. tube feet are located on the oral surface. e. stomach is everted to digest its prey.
An excitatory postsynaptic potential
a. is only one of several types of graded potential. b. has a hyperpolarizing effect. c. will drive the membrane away from its potential. d. is summed with an inhibitory postsynaptic potential at the input zone of a neuron in a process known as synaptic integration. e. is none of these.
How are the red blood cells produced in the body, and what might stimulate this process?
What will be an ideal response?