Most contemporary animal lineages first appeared between 530 and 520 million years ago, the time period referred to

as the ____ explosion.



a. Silurian
b. Cretaceous
c. Cambrian
d. Permian
e. Jurassic


ANSWER: c

Biology & Microbiology

You might also like to view...

A student observes a wormlike organism crawling about on dead organic matter. Later, the organism sheds its outer covering. One possibility is that the organism is a larval insect (like a maggot)

However, it might be a member of the phylum ________, and one way to distinguish between the two possibilities is by looking for the presence or absence of ________. A) Platyhelminthes; a cuticle of chitin B) Nematoda; an alimentary canal C) Annelida; a body cavity D) Nematoda; a circulatory system E) Annelida; muscle in the body wall

Biology & Microbiology

In the graph below, how can the change in infant mortality be explained as birth weight increases from 2 to 7 pounds?



A.  A larger baby will have more developed organs and thus have greater fitness.
B.  A baby closer to 7 pounds will have more developed organs and thus have lower mortality.
C.  A baby closer to 2 pounds will not be able to be delivered safely and thus have lower mortality.
D.  A baby closer to 7 pounds will have more developed organs and thus have higher motality.
E.  A baby closer to 7 pounds will not be able to be delivered safely and thus have higher mortality.

Clarify Question
· What is the key concept addressed by the question?
· What type of thinking is required?
· What key words does the question contain and what do they mean?        

  Gather Content
· What do you already know about fitness? How does it relate to the question?
 
Consider Possibilities
· What other information is related to the question? Which information is most useful?
 
Choose Answer
· Given what you now know, what information and/or problem solving approach is most likely to produce the correct answer?
 
Reflect 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?

Biology & Microbiology

Suppose a mutagen is used on an inbred population of mice to establish cell lines, each including a different mutant allele, which can then be tested for function. This technique is known as ________

Fill in the blank(s) with correct word

Biology & Microbiology

Refer to Figure 52-2. In this sequence of events the bell is serving as:

a. a motor stimulus. b. the conditioned stimulus. c. a cognition stimulus. d. a sign stimulus. e. the unconditioned stimulus.

Biology & Microbiology