Biology 211 Exam 1 - Iowa State University: Questions
With Expert-Approved Solutions
What are the 5 fundamental traits of life? With these traits in mind, are
viruses alive? What evidence supports your conclusion? Correct Answer -
-Energy Use and Metabolism
-Cell Theory
-Information, Genetics
-Replication or reproduction
-Biological Evolution
-No, viruses are not alive because they do not have cells.
How do hypotheses and theories differ? What do scientists mean by "theory"
and does this mean the same thing as "in theory" that non-scientists may say
in conversation? Explain. Correct Answer - A hypothesis is a constructed
idea before any applicable research has been done. A theory is an idea
supported by evidence.
When scientists say theory, they mean something that is true and supported
by evidence. When it is used in everyday conversations, it is simply an idea
that hasn't been proven, aka a hypothesis.
Write the Cell Theory in your own words. Did the Cell Theory challenge or
support the concept of spontaneous generation? Explain. Correct Answer -
Cell Theory: All cells come from pre-existing cells.
The Cell Theory challenged Spontaneous Generation and tested against it
through the Pasteur Flask Experiments.
Outline Pasteur's swan-necked flask experiment. What was the one variable
that differed between the test and experimental groups? Why is it important
to test one variable at a time? Correct Answer - Pasteur was comparing
the ideas of spontaneous generation and cell theory against each other. To do
this, he first set up an experiment where he had a straight neck flask filled
with broth. He boiled all of the bacteria out of the broth and left it to sit. After
a couple of days, there were bacterial cells. He then took a straight necked
flask and bent it into a swan necked flask. He then performed the same
experiment, boiling broth in both flasks and leaving them. After a couple of
weeks, the straight necked flask had bacterial cells in it again, but the swan
neck did not. Instead, the cells clumped inside the bend in the neck.
, It's important to test one variable at a time so that the experiment isn't
overwhelmed and you can keep track of each variable that you're testing.
What were the 2 claims made by Wallace and Darwin as they described the
process of evolution? Correct Answer - All species are related by
common ancestry and characteristics of species can be modified from
generation to generation because of natural selection.
What are the 2 conditions required for natural selection to occur? Would a
trait that increases the lifespan of each individual in the population but
decreases overall fertility lead to greater or lesser fitness of the affected
individuals? Correct Answer - Individuals must vary in characteristics
that are heritable and in a certain environment, certain versions of these traits
can help individuals reproduce more than other versions.
A trait that increases lifespans but decreases overall fertility would lead to
lesser fitness in the affected individuals.
What is the smallest unit that can evolve? Do individuals evolve? Correct
Answer - A population is the smallest unit that can evolve. Individuals do
not evolve.
If you continuously bred large-pod peas to other large-pod peas, would you
expect the average pod size to get smaller or larger? Why? What is this
process called? Correct Answer - You would expect the average pod size
to get larger because it is a desirable heritable trait due to natural selection.
Distinguish between fitness and adaptation? What organism are the most
evolutionarily fit? Correct Answer - Fitness is how well you produce
offspring and how well they produce offspring. Adaptation is a trait that
increases the fitness of an individual in a certain environment.
Diagram the central dogma of genetics. Label the 3 steps in order, from DNA
to protein. Correct Answer - Molecular machinery makes copies of DNA
in a closely related molecule known as RNA, which is translated into protein.
Why did Carl Woese and his colleagues compare ribosomal RNA to build their
phylogenetic trees? Could they have used the gene for a protein like keratin or
pilin? Why or why not? Correct Answer - Woese and his colleagues
compared ribosomal RNA to build their phylogenetic trees because it is very
With Expert-Approved Solutions
What are the 5 fundamental traits of life? With these traits in mind, are
viruses alive? What evidence supports your conclusion? Correct Answer -
-Energy Use and Metabolism
-Cell Theory
-Information, Genetics
-Replication or reproduction
-Biological Evolution
-No, viruses are not alive because they do not have cells.
How do hypotheses and theories differ? What do scientists mean by "theory"
and does this mean the same thing as "in theory" that non-scientists may say
in conversation? Explain. Correct Answer - A hypothesis is a constructed
idea before any applicable research has been done. A theory is an idea
supported by evidence.
When scientists say theory, they mean something that is true and supported
by evidence. When it is used in everyday conversations, it is simply an idea
that hasn't been proven, aka a hypothesis.
Write the Cell Theory in your own words. Did the Cell Theory challenge or
support the concept of spontaneous generation? Explain. Correct Answer -
Cell Theory: All cells come from pre-existing cells.
The Cell Theory challenged Spontaneous Generation and tested against it
through the Pasteur Flask Experiments.
Outline Pasteur's swan-necked flask experiment. What was the one variable
that differed between the test and experimental groups? Why is it important
to test one variable at a time? Correct Answer - Pasteur was comparing
the ideas of spontaneous generation and cell theory against each other. To do
this, he first set up an experiment where he had a straight neck flask filled
with broth. He boiled all of the bacteria out of the broth and left it to sit. After
a couple of days, there were bacterial cells. He then took a straight necked
flask and bent it into a swan necked flask. He then performed the same
experiment, boiling broth in both flasks and leaving them. After a couple of
weeks, the straight necked flask had bacterial cells in it again, but the swan
neck did not. Instead, the cells clumped inside the bend in the neck.
, It's important to test one variable at a time so that the experiment isn't
overwhelmed and you can keep track of each variable that you're testing.
What were the 2 claims made by Wallace and Darwin as they described the
process of evolution? Correct Answer - All species are related by
common ancestry and characteristics of species can be modified from
generation to generation because of natural selection.
What are the 2 conditions required for natural selection to occur? Would a
trait that increases the lifespan of each individual in the population but
decreases overall fertility lead to greater or lesser fitness of the affected
individuals? Correct Answer - Individuals must vary in characteristics
that are heritable and in a certain environment, certain versions of these traits
can help individuals reproduce more than other versions.
A trait that increases lifespans but decreases overall fertility would lead to
lesser fitness in the affected individuals.
What is the smallest unit that can evolve? Do individuals evolve? Correct
Answer - A population is the smallest unit that can evolve. Individuals do
not evolve.
If you continuously bred large-pod peas to other large-pod peas, would you
expect the average pod size to get smaller or larger? Why? What is this
process called? Correct Answer - You would expect the average pod size
to get larger because it is a desirable heritable trait due to natural selection.
Distinguish between fitness and adaptation? What organism are the most
evolutionarily fit? Correct Answer - Fitness is how well you produce
offspring and how well they produce offspring. Adaptation is a trait that
increases the fitness of an individual in a certain environment.
Diagram the central dogma of genetics. Label the 3 steps in order, from DNA
to protein. Correct Answer - Molecular machinery makes copies of DNA
in a closely related molecule known as RNA, which is translated into protein.
Why did Carl Woese and his colleagues compare ribosomal RNA to build their
phylogenetic trees? Could they have used the gene for a protein like keratin or
pilin? Why or why not? Correct Answer - Woese and his colleagues
compared ribosomal RNA to build their phylogenetic trees because it is very
