Warm Ups
Contemporary Biology N100, Spring 2001
Warm Up 1: Scientific Method, Evolution
QUESTION 1: What is the difference between a theory and a belief? You may want to look
these terms up before answering. Be as specific as you can, and
give an example of each.
QUESTION 2: What characteristic determines whether
organisms belong to the same species?
Why are, for instance, are Rottweilers, bulldogs, and poodles -
phenotypically (ie physical appearance) very different -
considered to be members of the same species - dogs? Why are all humans, despite our numerous
phenotypic differences, considered to be one species?
QUESTION 3: What does the term Survival of the Fittest mean?
How does the environment
influence the survival of an organism?
QUESTION 4: Totally
Optional: (ie none of my business): but if you would like to
answer this, I would like to hear your thoughts. I will not share
these answers with the class. Do you feel that there is an 'either / or' choice between your
religious beliefs and evolutionary theory - ie. that you must
reject the idea of evolution because of your religious beliefs,
or that you can't believe in God if you accept the evidence for
evolution? Is it possible to have both a belief in God and an
acceptance of the evidence supporting evolution?
See Selected
Student Responses to this Warm Up
Warm Up 2: Cells and Organelles
QUESTION 1: Cells are generally microscopic, ranging in size from about 50 microns for animal cells to as small as 1 micron for bacterial cells. Why do osite directions. Why do you think it is advantageous for the cell to maintain DNA as a double stranded molecule rather than a single-stranded molecule?
QUESTION 2: What happens if DNA is damaged? Do you think that this is something that occurs a lot in our cells, or only infrequently? What do you think are some things in the environment that cause damage and changes (mutations) in DNA?
QUESTION 3: Rosalind Franklin collected X-ray data crucial to the discovery of DNA's structure. However, she is hardly mentioned in some accounts of the discovery of DNA. Your textbook presents a short essay about the discovery of the structure of DNA (p. 149-150); read it and speculate why she might be less well known than Watson and Crick. Why was she not awarded a Nobel Prize in 1962 with Watson and Crick?
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Student Responses to this Warm Up
Warm Up 5: Mitosis / Chemotherapy
QUESTION 1: Each minute, 300 million of your body cells die!!! (Don't worry - these cells are replaced by mitosis, or you would be dead in a very short time!) However, some of the body's cells last for years, and some divide every day. List three types of cells in your body you would think would be replaced frequently. List 2 types of cells you think would be replaced slowly, if at all.
QUESTION 2: A protein called "p53" normally functions to find damaged DNA in the nucleus. p53 prevents cells from going through mitosis until the DNA damage can be repaired. However, smoking cigarettes frequently causes mutations in p53 in lung cells. How do think this might play a factor in the development of lung cancer?
QUESTION 3: Why do you think chemotherapy drugs, which are given to fight cancer, cause a person's hair to fall out?
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Student Responses to this Warm Up
Warm Up 6: Meiosis / Nondisjunction
QUESTION 1: Why do cells undergoing mitosis require one set of divisions, but cells undergoing meiosis require 2 sets of divisions? What is the end result of meiosis?
QUESTION 2: A common
error in meiosis in an egg (or a sperm) can result in trisomy, in which each somatic
cell of the of baby has 3
copies of one particular chromosome. Trisomy 21 is when an
individual has not 2 but 3
copies of Chromosome 21 in every one of their cells. Trisomy 21
is also called Down Syndrome. This is not in the book - but what
do you think happens in meiosis that would result in 3 copies of
Chromosome 21 in an embryo? Do you think there are other trisomys
in humans?
QUESTION 3: Chemicals such as alcohol and nicotine
can be teratogens.
What are teratogens and why are they so dangerous for a
developing baby? What does the name teratogen mean? How can heat
(like from a fever or use of a hot tub in early pregnancy) be a
teratogen?
QUESTION 4: Totally
Optional: Do you think the material we discuss in class has
relevance to y)
tells Allison that her mother is fine, but her father has lost a
lot of blood and will need a blood transfusion. Allison
volunteers to donate blood, and you tell her that her blood type
is AB. Bob is type O. (1) Can Allison donate blood to Bob? Why or
why not? (2) Allison, who is a biology student, begins to wonder
if she is adopted. What would you tell her and why?
QUESTION 3: When a
person is an 'albino', they have very pale (almost white) skin,
hair, and eye color. Yet, skin color, eye color, and hair color
are controlled by 3 different genes. How do you think a single mutation in a person can
cause all three of
these traits to be affected? (Hint: see Epistasis in notes)
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Student Responses to this Warm Up
Warm Up 10: Cloning/ GenEthics
QUESTION 1: Dolly the sheep is a genetic twin, or clone, of a sheep that was born 6 years earlier than Dolly. Read the material for today. Does Dolly have parents? If so, who were her genetic parents? Is Dolly a "virgin birth"?
QUESTION 2: What is the
flaw in thinking that if we were ever to clone a person, like
Einstein, a brilliant physicist, we would end up with another
brilliant physicist?
QUESTION 3: Can you think of a way that a person's
genetic information might be used to discriminate against them
for employment or insurance coverage? Give an example. How might
employers or insurance companies obtain this knowledge?
QUESTION 4: Comments,
questions, and totally optional: Can you think of any movies that
center around cloning, or are based around DNA in some way? If
so, what is the 'take-home message' of that movie?
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Student Responses to this Warm Up
Warm Up 11: Three Domains of Life
QUESTION 1: The Archaea
are thought to be the most ancient group of organisms, first
appearing on Earth about 3.5 billion years ago. The Archaea
include organisms that grow at extremes - very high (or low)
temperature, highly acidic or salty environments, needing neither
light or oxygen to grow. What does this suggest about the
environment on the Early Earth?
QUESTION 2: In the figure in your notes that shows
the three domains in different colors, what do the lines between
the different domains and different groups within domains
represent? Why are some lines short and some lines long?
QUESTION 3: If there was once a "Common
Universal Ancestor"that gave rise to the life forms we see
on Earth today, what do you think would have been some of the
characteristics of this organism? What types of events would have
led this Common Ancestor to branch off into the Three domains we
see today?
See Selected
Student Responses to this Warm Up
Warm Up 12: Student
Study Skills in N100: Does
the way this class is taught improve student study skills?
QUESTION 3: If world production of food were to
increase such that there was more than enough food for all the
people on the planet, why would 40,000 people still die of
starvation every day? Please read the notes before answering this
question!