Answer:
Carbon dioxide moves in; oxygen moves out
Explanation:
Answer:
Genotype of long winged fly is Ll
Genotype of short winged fly is ll
Explanation:
Given
Allele for long wing trait is "L"
Allele for short wing trait is "l"
When a long winged fly is crossed with a short winged fly, half of the offspring have long wings and other half have short wings as the ratio is 
Let us say that the genotype of long winged fly is Ll
and the genotype of short winged fly is ll
The cross between the two will produce following offspring
Ll * ll
Ll, Ll, ll, ll
Out of four off spring two have long wings (Ll)
and the other two have short wings (ll)
Thus the ration of long to short wing offspring is
i.e 
I guess that is:
Within the capillaries of the lungs, gases are exchanged by diffusion; O2 diffuses from the alveolus to the bloodstream and CO2 diffuses from the bloodstream to the alveolus.
Answer:
by having students draw germ cells and gemetes containing chromosomes with labelled alleles , instructors can assess student understanding of the structure of chromosomes .