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: 11459

#Unit 7. System Physiology – Animal

Partial or complete loss of hearing (deafness) can be caused by damage to the ________.

I) axons of the neurons associated with each hair cell that carry information to the brain

II) hair cells (the sensory receptors) in the cochlea

III) tympanic membrane, or eardrum

#Question id: 11095

#Unit 7. System Physiology – Animal

HIF-1 and HIF-2 can help increase the O2-carrying ability of the blood by

#Question id: 11120

#Unit 7. System Physiology – Animal

The release of neurotransmitter at a chemical synapse in the central nervous system is dependent upon which of the following?

#Question id: 11121

#Unit 7. System Physiology – Animal

Which of the following statements concerning the mechanoreceptive receptor potential is/are true?

#Question id: 11125

#Unit 7. System Physiology – Animal

In chemical synapses that involve a so-called second messenger, typically a G-protein linked to the postsynaptic receptor is activated when neurotransmitter binds to that receptor. Which of the following represents an activity performed by the activated second messenger?

#Question id: 11126

#Unit 7. System Physiology – Animal

Which of the following is characteristic of the events occurring at an excitatory synapse?