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#Question id: 13129


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? 

#Unit 10. Ecological Principles
  1. It increased in all three populations.
  2. It was unchanged in the largest population and increased in the two smaller populations. 
  3. It was unchanged in all three populations.
  4. It was unchanged in the two larger populations and declined in the smallest population.
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#Question id: 2253

#Unit 1. Molecules and their Interaction Relevant to Biology

Match the following lipid linked proteins (column I) with their function (Column II).

Column I

Column II

A. prenylated proteins

i. These proteins are located in a number of subcellular compartments, including the cytosol, the endoplasmic reticulum, the inner face of the plasma membrane, and the nucleus.

B. fatty acylated proteins

ii. The core structure of these proteins consists of phosphatidylinositol glycosidically linked to a linear tetrasaccharide composed of three mannose residues and one glucosaminyl residue.

C. glycosylphosphatidylinositol-linked proteins

iii. The proteins that have covalently attached lipids that are built from isoprene units

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#Question id: 2254

#Unit 2. Cellular Organization

If the intracellular [Ca2+] is 10−7 mol/L and the extracellular [Ca2+] is 2 × 10−3 mol/L, at what potential difference across the cell membrane will Ca2+ be at electrochemical equilibrium?

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#Question id: 2255

#Unit 2. Cellular Organization

Following statements are regarding to the Na+/K+ ATPase maintains the intracellular Na+ and K+ concentrations in animal cells. Which of the following statement is incorrect?

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#Question id: 2256

#Unit 2. Cellular Organization

Match the following inhibitors (Column I) with their effect (Column II).

Column I

Column II

A. A23187

I. endoplasmic reticulum Ca2+ ATPase inhibitor

B. valinomycin

II. Na+/K+ ATPase inhibitor

C. thapsigargin

III. K+ ionophore

D. ouabain

IV. Ca2+ ionophore

TLS Online TPP Program

#Question id: 2257

#Unit 2. Cellular Organization

Match the following property (Column I) with the transport mechanism (Column II).

Column I

Column II

A. Facilitated Transport

i. Requires specific protein

B. Active Transport

ii. Solute transported against its gradient

C. Cotransport

iii. Coupled to ATP hydrolysis

iv. Driven by movement of a cotransported ion down its gradient

TLS Online TPP Program

#Question id: 2258

#Unit 2. Cellular Organization

The arrangement of microtubules in eukaryotic flagella is referred to as