In some breast cancers, estrogen acts as a(n):

TLS Online TPP Program

#Question id: 2224

#Unit 2. Cellular Organization

Five dialysis bags, constructed of a type of membrane that is permeable to water and impermeable to sucrose, were filled with various concentrations of sucrose and then placed in separate beakers containing an initial concentration of 0.6 M sucrose solution. At 10-minute intervals, the bags were massed (weighed), and the percent change in mass of each bag was graphed.

Which line in the graph represents the bag with the highest initial concentration of sucrose?

TLS Online TPP Program

#Question id: 13164

#Unit 4. Cell Communication and Cell Signaling

Match the following.

Column I	Column II	Column III
A. G Protein–Coupled Receptors That Activate PDE	i. cAMP	a. Increase in conversion of glycogen to glucose
B. G Protein–Coupled Receptors That Activate Adenylyl Cyclase	ii. cGMP	b. Hyperpolarization or depolarization of photoreceptor membrane
C. G Protein–Coupled Receptors That inhibit Adenylyl Cyclase	iii. DAG	c. activates genes necessary for cell division
D. G Protein–Coupled Receptors That Trigger Elevations in Cytosolic and Mitochondrial Calcium		d. increase in K+ permeability hyperpolarizes the membrane

Which one of the following is correct?

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#Question id: 28439

#Unit 5. Developmental Biology

Hensen’s node is functionally equivalent to the which structure of amphibian? 

TLS Online TPP Program

#Question id: 28930

#Unit 4. Cell Communication and Cell Signaling

Hedgehog (Hh) presence causes__ 

a) binds to Smo, causing Smo to be endocytosed from the cell surface and degraded

b) binds to Ptc, causing Ptc to be endocytosed from the cell surface and degraded

c) degraded Ptc and relieving the inhibition of Smo

d) degraded Smo and relieving the inhibition of Ptc

TLS Online TPP Program

#Question id: 33347

#Unit 2. Cellular Organization

A rapidly growing bacterial species such as E. coli exhibits a typical phase of growth cycle in liquid nutrient broth (lag phase → log phase → stationary phase → death phase). If a bacterial culture has starting density of 10³ cells/ml has a lag time of 10 minutes and a generation time of 10 minutes, what will the cell density be at (cells/ml) 50 minutes?