A particular two-allele gene influences body size in the red-bellied black snake in Australia. Snakes with the BB genotype are largest, heterozygotes are intermediate in size and homozygous bb snakes are smallest. The cane toad is an invasive toad that was introduced to Australia in the 1930s and is highly poisonous to the red-bellied snake. Larger snakes are more likely to survive the poison. What likely has happened to the frequency of the two alleles in the snake population since the 1930s? The frequency of b has increased and the frequency of B has decreased. The frequency of both alleles has increased. The frequency of both alleles has decreased. The frequency of B has increased and the frequency of b has decreased.
Added by Kelly D.
Close
Step 1
Snakes with the BB genotype are the largest, heterozygotes are intermediate in size, and homozygous bb snakes are the smallest. ** Show more…
Show all steps
Your feedback will help us improve your experience
Suman K and 101 other Biology educators are ready to help you.
Ask a new question
Labs
Want to see this concept in action?
Explore this concept interactively to see how it behaves as you change inputs.
Key Concepts
Recommended Videos
Two genes control color in corn snakes as follows: $O-B-$ snakes are brown, $O-b b$ are orange, oo$B-$ are black, and $o o b b$ are albino. An orange snake was mated to a black snake, and a large number of $\mathrm{F}_{1}$ progeny were obtained, all of which were brown. When the $F_{1}$ snakes were mated to one another, they produced 100 brown offspring, 25 orange, 22 black, and 13 albino. a. What are the genotypes of the $F_{1}$ snakes? b. What proportions of the different colors would have been expected among the $F_{2}$ snakes if the two loci assort independently? c. Do the observed results differ significantly from what was expected, assuming independent assortment is occurring? d. What is the probability that differences this great between observed and expected values would happen by chance?
Katlin K.
6. A population of water snakes is found on a remote island. Some snakes are banded and some are unbanded. Banding is caused by an autosomal allele (b) that is recessive to the allele for no bands (B). Currently the population is in HW equilibrium for this trait, with genotype frequencies as follows: BB = 0.36, Bb = 0.48 and bb = 0.16. What would be the frequency of the genotypes in the next generation if inbreeding has started to affect the population, with an inbreeding coefficient of 0.2?
Reema C.
A scientist observed two populations of insects for 10 years. They took data on the length, in mm , of the insect’s mouthparts. Their data is shown in the graphs below. How is this population evolving and what agent of evolution is most likely at work? a. inbreeding, because the gene distributions are becoming less similar among the population b. genetic drift, as the distribution of traits has become more random c. gene flow, as the population has likely gained new mouthpart traits through immigration d. natural selection, as insects that have mid-sized mouthparts are being favored
Recommended Textbooks
Biology for AP Courses
Objective Biology for NEET
Introduction to General, Organic and Biochemistry
Transcript
18,000,000+
Students on Numerade
Trusted by students at 8,000+ universities
Watch the video solution with this free unlock.
EMAIL
PASSWORD