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Question
An accidental spill of a pesticide locally wiped out the most abundant species of butterfly in coastal California. Most of the bird species in the area had fed on this butterfly, but they switched prey to moths, and thus the birds showed only a small decrease in population size. The butterflies were a/an:
A) keystone species, and thus they were driven to extinction very easily.
B) endangered species.
C) ecological dominant, but they were not a keystone species.
D) pioneer species.
Answer
This answer is hidden. It contains 1 characters.
Related questions
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The sequence of development of sperm is:
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On average, about how often does ovulation occur?
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B) every 28 days
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Through what structure does an oocyte travel on its way to the uterus?
A) uterine tube
B) cervix
C) vagina
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If you could stop diffusion of substances in fruit fly zygotes, could you stop normal development? Why or why not?
Q:
Programmed cell death is also known as ________.
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You are a substitute teacher in a high school biology lab class on the day the students are dissecting frogs. A particularly bright student happens to notice that the left adrenal gland is malformed in her frog. She asks if a problem in embryonic development could have caused that. Although there may be more than one reason, what might you propose as an explanation based on embryonic development?
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Eye cells can become beak cells once they are committed.
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Cleavage and gastrulation take place in animals such as humans and birds but not in frogs.
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The blastula is the stage of embryonic development in which cells migrate.
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The end of a zygote that contains less yolk is the animal pole.
Q:
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A) sonic hedgehog
B) sonic chicken
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Q:
Which of the following is a process by which an initial set of genes turns on a second set of regulatory genes, which eventually turns on a third set of genes?
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B) gastrulation
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D) the genetic cascade
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Q:
What is the effect of higher concentration of bicoid protein in part of a fruit fly embryo?
A) It will develop into the posterior end of the organism.
B) It will develop into the heart of the organism.
C) It will develop into the head end of the organism.
D) It lowers the chances of embryo survival.
Q:
Of the choices listed, the first event that occurs during embryonic development is:
A) germ layer formation.
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Q:
The phase during which embryonic cells arrange themselves into three layers is called:
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B) gastrulation.
C) organogenesis.
D) fertilization.
E) induction.