Transcript 15_Active_Lecture_Questions

Chapter 15
Tracing Evolutionary History
Active Lecture Questions for
Biology: Concepts & Connections, Sixth Edition
Campbell, Reece, Taylor, Simon, and Dickey
Copyright © 2009 Pearson Education, Inc.
Concept Check
The timeline at the bottom of the screen represents
the history of life on earth. Which of the marked
periods represent the oldest fossil eukaryotes?
1) A.
2) B.
3) C.
4) D.
A
Earliest
evidence
of life
B
Pre-Cambrian Period
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C
D
Paleozoic Mesozoic Cenozoic Present
Answer
The timeline at the bottom of the screen represents
the history of life on earth. Which of the marked
periods represent the oldest fossil eukaryotes?
2) B.
A
Earliest
evidence
of life
B
Pre-Cambrian Period
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C
D
Paleozoic Mesozoic Cenozoic Present
Concept Check
The timeline at the bottom of the screen
represents the history of life on earth. Which of
the marked periods represent the Cambrian
explosion?
1) A.
2) B.
3) C.
4) D.
A
Earliest
evidence
of life
B
Pre-Cambrian Period
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C
D
Paleozoic Mesozoic Cenozoic Present
Answer
The timeline at the bottom of the screen
represents the history of life on earth. Which of
the marked periods represent the Cambrian
explosion?
3) C.
A
Earliest
evidence
of life
B
Pre-Cambrian Period
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C
D
Paleozoic Mesozoic Cenozoic Present
Concept Check
The timeline at the bottom of the screen represents the
history of life on earth. Which of the marked periods
represent the beginning of photosynthesis and the
accumulation of oxygen in the atmosphere?
1) A .
2) B.
3) C.
4) D.
A
Earliest
evidence
of life
B
Pre-Cambrian Period
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C
D
Paleozoic Mesozoic Cenozoic Present
Answer
The timeline at the bottom of the screen represents
the history of life on earth. Which of the marked
periods represent the beginning of photosynthesis
and the accumulation of oxygen in the atmosphere?
1) A.
A
Earliest
evidence
of life
B
Pre-Cambrian Period
Copyright © 2009 Pearson Education, Inc.
C
D
Paleozoic Mesozoic Cenozoic Present
Concept Check
The timeline at the bottom of the screen represents the
history of life on earth. Which of the marked periods
represent the extinction of the dinosaurs?
1)
A.
2)
B.
3) C.
4)
D.
A
Earliest
evidence
of life
B
Pre-Cambrian Period
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C
D
Paleozoic Mesozoic Cenozoic Present
Answer
The timeline at the bottom of the screen represents the
history of life on earth. Which of the marked periods
represent the extinction of the dinosaurs?
4) D.
A
Earliest
evidence
of life
B
Pre-Cambrian Period
Copyright © 2009 Pearson Education, Inc.
C
D
Paleozoic Mesozoic Cenozoic Present
Thinking like a scientist
Carbon-14 has a half-life of
about 5730 years.
Approximately, how old of
sample can you reliably date
using C-14 methods?
Copyright © 2009 Pearson Education, Inc.
1)
11,000 years
2)
25,000 years
3)
35,000 years
4)
40-50,000 years
Answer
Carbon-14 has a half-life of
about 5730 years.
Approximately, how old of
sample can you reliably date
using C-14 methods?
4)
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40-50,000 years
Thinking like a scientist
Which of the following
specimens could you best
date using Carbon-14
radiometric techniques?
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1)
Giant ground sloth
dung from the last ice
age.
2)
Early Cenozoic
mammal fossils.
3)
Dinosaur bones from
Colorado
4)
Early hominid fossils
from East Africa
Answer
Which of the following
specimens could you best
date using Carbon-14
radiometric techniques?
1)
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Giant ground sloth
dung from the last ice
age.
Thinking like a scientist
You’ve sent your pile of
ground sloth dung off to the
lab for analysis. The report
that you receive from the lab
indicates that your sample
has only about 10% of the
carbon-14 you’d expect in a
modern sample. About how
old is your dung sample?
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1)
6,000 years old.
2)
12,000 years old.
3)
18,000 years old
4)
24,000 years old
Answer
You’ve sent your pile of
ground sloth dung off to the
lab for analysis. The report
that you receive from the lab
indicates that your sample
has only about 10% of the
carbon-14 you’d expect in a
modern sample. About how
old is your dung sample?
3)
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18,000 years old
Science and Society
The science of cladistics is reshaping phylogenetic trees.
Along with this analysis cladists are also proposing new
taxonomic terminology to reflect the new understandings of
systematics. This terminology at this time is rather challenging
and not at all like the terminology that the general public is
familiar with. For instance, most people think that vertebrates
fall into the classes of fish, amphibians, reptiles, birds and
mammals. These categories are inconsistent with cladistic
analysis. Should classical terms be kept despite their
inaccuracies?
Strongly
Disagree
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A
B
C
D
E
Strongly
Agree
Science and Society
Some estimate the extinction of species (mostly due to habitat
loss) to be on the order of hundreds of species a year.
Analysis of the fossil record indicates that normal background
extinction rates are on the order of a few species a year. For
this reason, some scientists have suggested that the earth is
currently experiencing a major extinction event much like the
great extinctions of the past—only this one is primarily human
caused. Do you agree that the current extinction rates are
cause for alarm?
Strongly
Disagree
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A
B
C
D
E
Strongly
Agree
Science and Society
Some people rationalize species loss as organisms that can
not adapt go extinct—it’s part of natural selection. Do you
agree that species extinction due to human causes are natural
events?
Strongly
Disagree
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A
B
C
D
E
Strongly
Agree