Pick a biological situation where a positive feedback loop controls a response. Show how this loop operates to bring about the response
What will be an ideal response?
Most of the possible responses are those involving development or reproduction. Possible examples are: 1 ) courtship and mating, 2 ) molting of the cuticle in insects, 3 ) metamorphosis in insects, frogs, or any animal with a larval form, 4 ) childbirth, intercourse and orgasm, a sneeze, nerve impulse transmission. Any process that involves a directional change can qualify. A complete answer should include information showing that the animal passes through this directional change in controlled stages, sensing the completion of one step before proceeding to the next.
You might also like to view...
Consider two islands located an equal distance from the mainland (colonization source). One island is large, the other is small. Which island will have a higher rate of change in species composition?
A. the small island B. the large island C. The rate of change in species composition will be the same on both islands. D. Species composition does not change at equilibrium.
The figure shows a cladogram of direct development versus development of a larval stage. Choose the true statements about the evolution of development in limpets.
_____ Loss of structures in the transition from a larval stage to direct development prohibits evolutionary reversal.
_____ Direct development has evolved multiple times.
_____ Evolution always proceeds parsimoniously.
_____ Possession of a larval stage is the ancestral state in limpets.
Heavy harvesting of which species during the 1970s reduced the population to about one percent of its original size?:
a. Bombus occidentalis, the western bumblebee b. Haliotis sorenseni, the white abalone c. Juga newberryi, a freshwater snail d. Pyrgulopsis owyheensis, a springsnail e. Capnia kersti, a stonefly
After the evolution of the vertebral column,
what is the correct order of vertebrate innovations as they appear in time?
a. jaws>>>lungs>>>paired limbs>>>amniote egg b. jaws>>>paired limbs>>>lungs>>>amniote egg c. paired limbs>>>lungs>>> jaws>>>amniote egg d. amniote egg>>>jaws>>>lungs>>>paired limbs e. jaws>>>paired limbs>>>amniote egg>>>lungs