Seriously abnormal phenotypes or harmful mutations are acted against or reduced to low frequenciesby:a
beneficial mutations.
b. gene flow.
c. disruptive selection.
d. genetic drift.
e. natural selection.
E
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The most common source(s) of infection in the central nervous system (CNS) is(are):
a. hematogenous spread. b. infections at other sites such as otitis me-dia. c. organisms gaining access because of ana-tomic defects in CNS structures. d. bacteria that are able to travel along nerves leading to the brain.
Insects use ____ as a respiratory system
a. integument exchange b. lungs c. tracheal exchange d. gills e. none of these
One spring, your friend living in Minnesota eagerly sets up her new hummingbird feeders, and is thrilled to watch hummingbirds feeding on the nectar. However, she is disappointed when after just a week or two the hummingbirds disappear. What advice would you give her?
A. Set up a bell (conditioned stimulus) near the feeders so the hummingbirds make an association with the food. B. Set up flashing red lights that mimic the male neck feathers -- that should attract more males to the area. C. Set up the feeders again in the fall. The hummingbirds may have briefly traveled through during their annual spring migration. D. Wait till next year -- hummingbirds are a high-metabolism, semelparous species and have already reproduced and died. Clarify question: What is the key concept addressed by the question? What type of thinking is required? Gathering Content: What do you already know about feeding behaviors in birds? What other information is related to the question? Choose Answer: Given what you now know, what information is most likely to produce the correct answer? Reflection on Process: Did your problem-solving process lead you to the correct answer? If not, where did the process break down or lead you astray? How can you revise your approach to produce a more desirable result?
Which muscle contraction is involuntary?
A. Cardiac and smooth B. Skeletal only C. Cardiac, smooth, and skeletal D. Smooth only E. Cardiac only