#Question id: 13129
#Unit 10. Ecological Principles
Biologists performed an experiment with flies to examine the effects of population size on the maintenance of genetic variation and on egg-to-adult survival. From a large source population, they randomly assigned eggs to three experimental populations of size N, equal to 20, 60, and0100. For later generations, they collected N eggs from each population and moved them into identical vials that co0ntained f2re0sh me4d0ium. Th6e0y coun8te0d the number of adult flies that emerged and used tissue samples from the adults for genetic analyses. Genetic variation was measured by scoring alleles at several polymorphic loci and expressed as the average number of alleles at those loci. The results are summarized in Figure 1 and Figure 2 below.
Based on Figure 1, which of the following best describes the change in genetic variation over time?
#Question id: 4327
#Unit 3. Fundamental Processes
What would occur if the repressor of an inducible operon were mutated so it could not bind the operator?
#Question id: 11956
#Unit 7. System Physiology – Animal
An advantage of a complete digestive system over a gastrovascular cavity is that the complete system ________.
#Question id: 7215
#Unit 5. Developmental Biology
Limb bud initiation could have either initiation
factors
genomes Listed below
are some limb bud initiation (Column A), their lateral plate mesoderm (Column
B).
A |
B |
|
a. Hindlimb bud |
1.
Tbx4 |
(x).
Wnt8c |
2.
Islet1 |
||
b. Forelimb bud |
3.
Tbx5 |
(y).
Wnt2b |
4.
Pitx1 |
#Question id: 31124
#Unit 2. Cellular Organization