The maternal-effect mutation bicoid (bcd) is recessive. In the absence of the bicoid protein product, embryogenesis is not completed. Consider a cross between a female heterozygous for the bicoid alleles (bcd⁺/bcd⁻) and a male homozygous for the mutation (bcd⁻/bcd⁻).

Predict the outcome (normal vs. failed embryogenesis) in the F₁ and F₂ generations of the cross described.

Video transcript

Hi everyone. Let's take a look at this practice problem Together. The bike oID B. C. D. Gene is involved in the development of the anterior posterior access of the Drosophila embryo. If the concentration gradient of bike oid protein is traced, it shows a blank trend from the embryo's anterior end towards the posterior end. So from this question we know that this bike oid gene is important in Drosophila embryo development and that it works through a concentration gradient. So is the movement of the bike Oid protein increasing, decreasing or consistent. Well recall that a concentration gradient is the movement of particles from an area of high concentration to low concentration. So in this illustration you would have the particles moving from the left to the right side. Therefore if the bike oid protein concentration started at the anterior end that would be the high and the low would be the posterior end. So movement would be from high to low anterior to posterior which means our answer is be decreasing. Alright everyone I hope you found this helpful and I'll see you soon for the next practice problem.