Biology 101A
FINAL Opportunity to Succeed
23 April, 1998

LINK to TEXT-ONLY version

100 points Total, 10 points per question.
 

Lecture # 4 - Chapter 3: Biological Molecules

1.  (10 pts.) List the four principle building blocks of biological molecules.   Explain what the monomeric unit and the polymerized product is for each.
 
 

ANSWER:
see learning objectives # 1 and # 2 from 21-Jan-98
 

 

Lecture # 6 - Chapter 10: DNA is like Coca-Cola
 

2.  In class we talked about FOUR MAJOR COMPONENTS of DNA, that had correspondingly similar components in Coke. Consider the following bases, shown below.

see learning objective # 1 from 6-Feb-98

1. WATER,
2. SUGAR (deoxyribose for DNA, sucrose for Coke),
3. PHOSPHATE

A-DNA
B-DNA
Z-DNA

(up to 2 points) The bases would stack on top of each other and form a (single-stranded)  HELIX.
 

(up to 2 points) This is known as "spontaneous self-assembly", and could well be how the early precursor to RNA formed.  (It is presently thought that RNA was the first "living molecule", and that both proteins and DNA evolved much later...)
 
 

Lecture # 14 - Chapter 13: Patterns of Inheritance

3.  Farmer Billy-Bob Jones is curious about why some of his corn ain't all yeller, like it SHOULD be. He picks up a cob at random, and counts all the different seed. The numbers he finds are as follows:

 

3b. (3 pts.) Using the letters "Y" for Yellow, and "y" for purple, write the genotypes of the three different colours of corn seed.
 
 
 
 

3c. (3 pts.) Farmer Billy-Bob planted homozygous seeds last year, and the crop this year is a result from two different pure-breeding strains of maize. What is the genotype of the two crops he planted last year?
 
 
 

3d. (2 pts.) Which colour is dominant?
 
 
 
 
 
 
 
 
 

Lecture # 24 - Chapter 19c: History of Life: the Last Billion Years (or so)

4. (10 points)  List the four major geological eras describing the history of the earth, and describe the types of living organisms one might find within each era.
 
 
 
 
 
 
 

Lecture # 26 - Chapter 20: Taxonomy: Imposing Order on Diversity

5.  (10 pts.) List the 7 major categories for classification of living organisms.
 

(you know, Kingdom, Phylum, Class, Order, Family, Genus, Species!)

Lecture # 32 - Chapter 23: Nutrition, Digestion, and Excretion

6. (10 pts.) How long (in hours) would you have to walk to burn off the calories from a "Whopper with cheese"?  (note: this contains about 730 calories, and 46 grams of fat.)
 
 
 
A (maybe) HELPFUL HINT: It could be very useful to have read carefully through pages 421-427 in Chapter 23, and to know how to calculate how long it would take to burn off a given amount of calories jogging (11 cal/min), walking (3.8 cal/min), or sitting quietly (1.7 cal/min).  Also, you might want to remember that there are roughly 9 calories per gram of fat, and 4 calories per gram of protein, and 4 calories per gram of carbohydrate.  Here is an example of a simple calculation I expect you to be able to do:

Question: How many hours would it take to burn off a whopper with cheese, if you were to sit quietly?? 

730 calories from cheeseburger * 1 min/1.7 cal = 429 minutes  = 7.1 HOURS

Please note that the full answer is in hours (because the question I asked was HOW MANY HOURS).
 
 
 

Essay questions - the last four questions on the exam will be a "short essay" format.  Please answer the question clearly, in complete sentences, and make sure what you write fully addresses the question.  There are several different possible correct answers, but there are also a large number of possible wrong answers.  I will grade your answer mainly on how clearly and succinctly you can address the question.  (For some people, this method of grading might seem to be a novel approach!)
 

Lecture # 1 - An Introduction to Life on Planet Earth

7. (10 pts.)  You have a friend who tells you that science is based on people's opinion - kind of like a democracy.  Science is decided by a bunch of people getting together and the most popular idea is decided to be the "correct one".    Compare this idea with the "Scientific method" as outlined in Chapter 1 of your text.
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

8. (10 pts.) Compare and contrast prokaryotes vs. eukaryotes.  Include in your discussion the organization and relative sizes of the cells of both organisms, the role of cell membranes (including eukaryotic organelles), and the evolutionary relationship between bacteria, archaebacteria, and eukaryotes.
 
 
 
 
 
 
 
 
 

9. (10 pts.) Explain what is meant by the "discovery of deep time", and why this is important in evolution.  Until about a hundred years ago, there were two commonly held beliefs about the age of the Universe.  What were these two beliefs, who held them, and why were they BOTH wrong?  Be sure to include in your answer the approximate age of the Earth, when the first rocks formed, and when the first fossilized bacteria formed.
 
 
 
 
 
 
 
 

 

10.  (10 pts.) The article below is from Tuesday's Washington Post (21-Apr-98).  Why should scientists be concerned about the extinction of species?  After all, the 30,000,000 or so species that are alive today are only a tiny fraction of the 5,000,000,000 species that have roamed the earth in the past.  Include in your answer the importance of "community interactions".
 

Mass Extinction Underway, Majority of Biologists Say  By Joby Warrick  Washington Post Staff Writer  Tuesday, April 21, 1998; Page A04     A majority of the nation's biologists are convinced that a "mass extinction" of plants and animals is underway that poses a major threat to humans in the next century, yet most Americans are only dimly aware of the problem, a poll says.    The rapid disappearance of species was ranked as one of the planet's gravest environmental worries, surpassing pollution, global warming and the thinning of the ozone layer, according to the survey of 400 scientists commissioned by New York's American Museum of Natural History.    The poll's release yesterday comes on the heels of a groundbreaking study of plant diversity that concluded at least one in eight known plant species is threatened with extinction. Although scientists are divided over the specific numbers, many believe that the rate of loss is greater now than at any time in history.    "The speed at which species are being lost is much faster than any we've seen in the past -- including those [extinctions] related to meteor collisions," said Daniel Simberloff, a University of Tennessee ecologist and prominent expert in biological diversity who participated in the museum's survey.    Most of his peers apparently agree. Nearly seven out of 10 of the biologists polled said they believed a "mass extinction" was underway, and an equal number predicted that up to one-fifth of all living species could disappear within 30 years. Nearly all attributed the losses to human activity, especially the destruction of plant and animal habitats.    Among the dissenters, some argue that there is not yet enough data to support the view that a mass extinction is occurring. Many of the estimates of species loss are extrapolations based on the global destruction of rain forests and other rich habitats.    Among non-scientists, meanwhile, the subject appears to have made relatively little impression. Sixty percent of the laymen polled professed little or no familiarity with the concept of biological diversity, and barely half ranked species loss as a "major threat."    The scientists interviewed in the Louis Harris poll were members of the Washington-based American Institute of Biological Sciences, a professional society of more than 5,000 scientists.         © Copyright 1998 The Washington Post Company

 EXTRA  CREDIT
(up to 10 points)

Compare the above article with the "scientific method" philosophy addressed in your answer to question # 6.   What (if any) logical errors has the author of the Washington Post made in their assessment of how science works?  Should scientists wait for a complete agreement on an issue that has global implications?  (For example, should we wait until we can unequivocally see the temperatures increase by 5 degrees C before we warn about global warming?)