I. Oxytocin causes contraction of the smooth muscle of the uterus.

II. The suckling of an infant at the breast stimulates the touch receptors, the nuclei are stimulated, oxytocin is released.

III. The sensitivity of the uterine musculature to oxytocin is enhanced by estrogen.

IV. Progesterone directly stimulates myometrial contraction while simultaneously reducing oxytocin clearance.

#Question id: 26978

#Unit 10. Ecological Principles

If the organism have survival of juveniles and adult is poor, selection pressure favors in these organisms

#Question id: 26979

#Unit 10. Ecological Principles

If the organism have survival of juveniles and adult is poor, selection pressure favors in these organisms

#Question id: 26980

#Unit 10. Ecological Principles

Which of the following statements about the selection pressure is incorrect?

a.If survival of juveniles and adult is poor then selection favours a single act of reproduction

b.If survival of juveniles and adult is poor and unpredictable then selection favours repeated reproduction and long reproductive life

c.If the environment is stable then selection favours a single act of reproduction.

d.If survival of juveniles is very poor and unpredictable but adult are more likely to survive then selection favours repeated reproduction and long reproductive life

e.If survival of adult is unpredictable but juveniles are more likely to survive then selection favours a single act of reproduction

#Question id: 26981

#Unit 10. Ecological Principles

Life history features of r-selected species is

#Question id: 26982

#Unit 10. Ecological Principles

Which of the following statements about the evolution of life histories is correct?

a.Unstable environments with unlimited resources favor r-selected populations.

b.K-selected populations are most often found in environments where density-independent factors are important regulators of population size.

c.Most populations have both r- and K-selected characteristics that vary under different environmental conditions.

d.The reproductive efforts of r-selected populations are directed at producing just a few offspring with good competitive abilities.

#Question id: 26983

#Unit 10. Ecological Principles