BIO 20 Exam 2 (Brett Holland CSUS)

Read the article at the link below. Then select those statements supported by the article. Note: what most people call a "calorie" is actually a "kilocalorie" (1000 calories). This article uses kcal. In this class I use calorie because that is what most of you are accustomed to. For example a 150 calorie soda is technically 150 kcal.

"obesity doesn't cause diabetes: sugar does." was in the original article. sugar positively correlates with diabetes; duration of sugar exposure positively correlates with diabetes; diabetes probability increases with more sugar and decreases with less sugar. people who consume more sugar are more likely to become diabetics. sugar is a toxin in our modern culture. for every 150 sugar calories (e.g., 12 ounces of soda or juice) introduced per person per day into a country's food system, the rate of diabetes goes up ~1 percent. The study statistically removed variables: poverty, urbanization, aging, obesity and physical activity.

What would be the maximum number of codons if codons consisted of two bases instead of three?

16

Based on evolutionary theory, the minimum number of full siblings you should be willing to die for is [x1]? That is, what is the number at which your fitness neither gains nor loses? Assume that you are all identical except for your genes. Enter a whole number.

2

The estimate of the number of genes in the human genome has dropped steadily over the last 40 years. Recently the number has changed more slowly. approximately what is the current number?

20,000

A cubic cell with a length of 1 unit increases in length by 6 times its original length. Approximately, how many times greater is the oxygen demand of the cell? that is, how much more oxygen is required?

216

What would happen if there were 3 different pairs of bases used to form the double helix? (e.g., A/T, G/C, E/F). How many codons would be possible? (All else is the same, e.g. 3 bases per codon).

216

A cubic bacterium with a length of 1 unit increases in length by 17 times its original length. How many times greater is its ability to transfer nutrients and wastes to/from the cell?

289

How many thousands of bases (kb) is the human genome?

3,000,000

Imagine a cell shaped like a cube. A mutation causes the surface area to increase by 4 times. The new volume will be [x1] times greater than the original volume. Enter a whole number.

8

In Lewis Carroll's Through the Looking-Glass, the Red Queen tells Alice, "in this place it takes all the running you can do to stay in the same place." How is this statement logically connected with the idea of evolution by natural selection?

As populations adapt to their enemies, their enemies counter adapt in turn.

Which are true (choose 4)

Bacteria can evolve as much in 1 day as humans can in 1,000 years. Tuberculosis was rare in the US by 1985, but now is becoming more common in the US and more resistant to antibiotics. The antibiotic era started by accident when penicillium mold was seen to inhibit bacterial growth on a petri dish. We are exposed to antibiotics from meat and dairy products, therefore, bacteria within us may be selected for resistance to them.

Which are true of iron?

Bacteria need it. Bacterial infections can sometimes be prevented by withholding it. Bacterial infections may be increased by supplementing it in host diets. In response to an infection the body releases a chemical that reduces iron availability in the blood. Iron binding proteins in human milk are 10X more common than cow milk (as a percentage of total iron) Egg white probably helps protect the yolk from infections.

Ultimately, why have we evolved thumbs?

Because human ancestors who had thumbs left more offspring than those without thumbs.

Why did circulatory systems evolve? Choose two.

Because the diffusion of things to and from cells (oxygen, nutrients, and waste products) was too SLOW in large multicellular organisms. The surface area-to-volume ratio decreases as organism size increases.

Unintended consequences of anaboloic steroid use include:

Breast tissue in males. Hypertension. Coronary disease. Heart attack. Aggression and violence.

The Rose experiment with fruit flies is very famous among evolutionary biologists. I do not think it was clearly explained by the authors. I hope it was clearly explained in lecture. I suggest you review what you learned in lecture about the evolution of aging. How did the experimenters get flies to evolve longer average lifespans?

By experimental evolution (natural selection in a controlled environment): Those flies that aged more slowly were able to lay more eggs later in life than those that aged quickly. Therefore, genes for longevity were better represented at the time of egg collection.

The energy needed to raise the temperature of 1 kg of water 1 °C (nutrition definition). Scientists use 1 g instead.

Calorie

May temporarily double one's glycogen storage.

Carbo-loading

Any chemical with an atomic ratio of 6 carbon, 12 hydrogen and 6 oxygen.

Carbohydrate

Which of the following are true of cellulose?

Cellulose and starch are made from different forms of glucose. The cellulose we eat passes through our digestive system without being broken down. Although it is not digestible, cellulose is still important to humans' diets.

The Russian-American biochemist Phoebus Levene was the first to determine that nucleotides may contain one of four different nitrogen-containing bases. Levene believed that the nitrogen-containing bases occurred in equal amounts in DNA. What is the actual proportion of these bases?

DNA contains equal amounts of adenine and thymine, and equal amounts of guanine and cytosine.

The central dogma of molecular biology describes how information is converted into organisms. Which, below, describe this?

DNA is transcribed into RNA which is translated into protein.

Natural selection ultimately acts on individuals, not genes.

False

Social Darwinism is an important contribution to intellectual thought because it can inform our values.

False

Steroid injections can increase muscle mass or decrease recovery time from extreme exercise. They can also decrease testes size because ____? Choose all that contribute.

Feedback inhibition. Negative feedback. Testosterone is made in the testes.

Which are environmental toxins that we are exposed to?

Heavy metals Radon gas Insecticides Air pollutants Nitrates in food

What is the authors' purpose for WWGS ?

It applies natural selection and other ultimate (evolutionary) perspectives to understand why we are imperfect

Which are true of ethanol

It is toxic to cells that it contacts It is addictive It is detoxified in the liver It is a neurotoxin

Storage locations for glycogen

Liver and muscle

Which are true of hosts and infectious agents?

Medicines that block unpleasant symptoms may sometimes increase the duration and severity of the infection. It can be unclear who causes what (e.g., sneezing). To know what to do about a symptom of an infectious disease we need to have research that determines who is benefiting (whose adaptation it is). Some pathogens can manipulate the behavior of their host to get themselves transferred to a new host (e.g. rabies) The rabies virus infects neurons and particularly those that mediate aggression. Menstruation may be an adaption to expel bacteria from the reproductive tract. Some viruses and bacteria use chemical cues that mimic our own proteins in order to gain entry into cells.

Use the Codon table (DNA-to-amino acid) from lecture notes to determine the amino acid sequence that would be produced from the DNA sequence below. A T G T G A C A T A T G G C A C A T

Met

Use reliable web sites (i.e., peer-reviewed and the articles they reference) as needed to determine which of the following assertions about the drug, "spice"/"K2", are true.

New drugs are generally dangerous because there is a lack of data on their side-effects and long term consequences. It can induce psychosis in people with no previous episodes of psychosis most of the synthesized cannabinoids are not found in cannabis, therefore is should not be thought of as simply strong cannabis. It is also marketed as "herbal incense"

Which of the following are features that distinguish cancer cells from normal cells?

Normal cells can divide a finite number of times; cancer cells can divide indefinitely. Normal cells have contact inhibition; cancer cells have no contact inhibition.

What was Mark Twain's insight into anxiety?

People suffer from problems that don't actually exist.

Which are true of plants and their toxins?

Plant tissues more likely to be edible are nuts protected by hard shells or those that are hidden. There is a trade-off between defensive toxicity and growth rate for plant tissue. When an aspen leaf is damaged it releases a chemical that causes leaves around it, even on other trees, to produce anti-herbivore compounds.

What are some of the dangers (or potential dangers) of designer drugs and/or other drugs? Ignore the answer choices with no answers (Glitch).

Safety tests generally last for months yet people often take drugs for years or decades. Synthesizing new drugs for recreation may become commonplace as our understanding of brain chemistry deepens. Using drugs to avoid dealing with unpleasant aspects of one's life, that are themselves opportunities for personal growth (e.g., mild/manageable anxiety, depression, loneliness, etc. As opposed to the appropriate use of drugs with the guidance of a physician, to deal with overwhelming traits, like excessive/harmful anxiety, depression, etc.).

Which are true concerning fats?

Saturated fats contribute to strokes and heart attacks Saturated fats contribute to narrowing arteries Saturated fats are found primarily in the animal products we eat A diet with a high unsaturated-to-saturated fat ratio is healthier than the alternative

The exterior tissue of a lady bug is

Skeleton

The authors indicated that sunscreen may be counterproductive because it does not screen out all UV. PLEASE NOTE: Sunscreens have been improved since the publication of this book; they filter UV much more thoroughly. It is now recommended by the medical community that sunscreen be used outdoors. Which are true (using current information)?

Sunscreen decreases the risk of skin cancer. Some sunglasses do not block UV. These are worse than no sunglasses with respect to developing cataracts.

Use the internet to evaluate the following assertions. The goal is not to find websites that repeat an assertion, but to find sites that cite evidence. Based on your reading, which are true:

Taurine is synthesized within our body. Taurine is a natural component of a typical diet. Taurine has a number of physiological functions.

The authors refer to natural selection favoring traits that are 'good for the species, population, or group'. This is known to be extremely rare. However, it is still a commonly held belief by non biologists and those biologists who do not have a strong background in population biology. Aside from perpetuating this one discredited idea, the authors do a good job of including true information. Almost all genes evolved by natural selection because they increase the reproductive success of the individuals expressing them. To understand why genes and traits are selected by virtue of their effect on the individual expressing them, instead of their population, consider what would happen to the (altruistic) genes that cause an individual to not reproduce (e.g., because there wasn't enough food for everyone in the population)? You will not find the answer in LOG. If you cannot determine the answer from above, Google, "group selection" and read about it at wikipedia.

The alternative alleles in the population that do not cause altruism would increase in frequency, eventually driving the altruistic genes to extinction. The population would only slightly benefit but the altruist would severely suffer (zero reproductive success) The altruist would not tend to pass on the alleles that contributed to that altruistic behavior.

Imagine a hypothetical species just like humans except the average lifespan is 100 years. What would happen to a new mutant allele that made individuals reproduce relatively more when age 25 but also made them more likely to die sooner after the age of 80? Imagine the mutation gives one greater energy, or, desire to have a family, or simply greater sexual desire when age 25, but also results in greater risk of cancer after age 80. You will not find the answer in LOG.

The average number of offspring produced by people with this allele would be greater than those without the allele. The allele would increase in frequency at the expense of the alternative alleles at that locus. The average lifespan in the population would eventually decrease as the allele became common

Regarding fear and pain, the authors imply:

There is an optimum amount of both. Too little and you are more likely to die young. Too much and you are inhibited.

Which of the following statements is true of amino acids?

They combine to form polypeptides. They make the diversity of life's structures possible. They differ in shape, size, and electrical charged. They are the building blocks of proteins. They are organic molecules possessing both carboxyl and amino groups.

Why are gall bladder cells different from lung cells?

They express their genes differently.

Which of the following statements is true of amino acids?

They make the diversity of life's structures possible. They differ in shape, size, and electrical charged. They are organic molecules possessing both carboxyl and amino groups. They are the building blocks of proteins. They combine to form polypeptides.

What are 3 likely reasons given by the authors to explain why Lemmings actually jump into water during spring snow-melts?

They may want to get to the other side. They are migrating. Someone with a broom pushes them in.

Why are alcohol and tobacco legal recreational drugs?

They were an accepted part of the culture of the people who formed this country. They are very profitable products. Part of their profit is directed, through lobbyists, to reelection campaigns of Congress people who support the drug maker's goals.

Read the article below and choose the correct statements below. Some answer choices will require you to search for information on the web by using words/information from the article or web page. The history of vaccination and disease is similar to that seen in the US. To put the numbers in perspective, the population of the UK is approximately twice that of California.

This article is published in the United Kingdom by a publicly funded health agency. Greater than 150 new vaccines are being tested. At the worst point in the history of the infection, polio paralyzed approximately one thousand children around the world every day. There is currently a resurgence of whooping cough in CA. In the 1970s and 80s, parents stopped vaccinating their children against whooping cough. This led to three epidemics, and at least 100 children died after catching the disease.

Which of the following are, or describe, mechanisms of aging (broadly defined as decreased function and increased disease in proportion to age)?

Trade offs: genes that make you good at reproducing when young, will sometimes cause you to deteriorate faster when older. Shortening of telomeres. beta-amyloid plaques Free radicals. Shortening the ends of chromosomes.

A shot of hard alcohol kills millions of esophageal and stomach cells on contact

True

Overall, toxin exposure has probably decreased in modern times relative to that experienced by most of our ancestors.

True

Why are there 3 bases per codon?

Two would not code for enough (20) amino acids. Four would be a waste of DNA.

Most of the following are correct. Find them.

Variation in bacteria is being generated every day due to new mutations. There will be variation among the bacteria for their harmfulness (virulence). Those individual bacteria that are less harmful are less likely to kill their host. Those bacteria that reproduce the fastest will leave more descendants and therefore be more likely to be transmitted to a new host. Faster bacterial reproduction means greater virulence. If the behavior of humans changes, this can exert an evolutionary change in the pathogen population Increased promiscuity can cause the evolution of increased virulence of STD's because they are more likely to be transmitted before their host dies. Condoms and clean needles, in addition to preventing transmission, extend the average time until transmission and therefore also select for less virulent strains. Within an infected human there can be billions of a pathogenic bacteria.

What is the central paradox exposed by WWGS?

We possess intricate adaptations yet still suffer from crude problems

Match each word or phrase with the most accurate definition. Most of these words are used throughout this course (not necessarily in this chapter). This is a good question for Google assistance.

When during development, how much, and in what location (which cells), a protein is produced: gene expression The cell lineage within all multi-cellular organisms that produces gametes: Germ A time series of something, for example, you and all of your direct ancestors back to the beginning of life; or, a cell and all of its ancestors back to the beginning of life: Lineage Reproductive cells that fuse to form a new individual: Gametes A sequence of DNA, usually near a gene, that controls when that gene is turned on/off, how much transcription occurs, and therefore, how much protein is produced: Regulatory The act of copying DNA into mRNA (messenger RNA): Transcription The act of reading the information encoded in a mRNA sequence and creating a protein with a corresponding sequence: Translation The building blocks of any protein: Amino Acids

Which are true?

Women who do not have pregnancy nausea are more likely to have children with birth defects. Actively metabolizing tissues are more vulnerable to toxins than dormant ones. Embryonic and fetal tissue is more sensitive to toxins than adult tissue. Morning sickness may be an adaptation to avoid toxins. Bendectin, or anything else that reduces pregnancy nausea may be an indirect teratogen. Children's dislike of pungent vegetables may actually be a healthy adaptation to avoid toxins. Women who do not have pregnancy nausea are more likely to miscarry. Embryos and fetuses are more sensitive than adults to toxins found in alcohol, tobacco and coffee.

Use the the web to find the two primary sugars found in honey. Is there any reason why you might not want to make honey your principle sweetener?

Yes. It is high in fructose, which we can only metabolize in our liver

Multiple atoms joined together are collectively called? If you google two key words (atom and joined) you might get a good hit. Or you can think of a more technical chemical term for *joined*.

a molecule

An amino acid is to a polypeptide as ____ is to ____. (choose the best 3)

a nucleotide is to RNA. glucose is to glycogen. glucose is to cellulose

During transcription, at the point where the DNA strand being copied has an adenine, _______________ is added to the mRNA.

a uracil

Genotype is to phenotype as: (pick the 3 best)

alphabet is to book software language is to i-phone application recipe is to dinner

Which are benefits of exercise?

appetite suppression stress reduction healthier life saving money (if commuting by bike or walking) longer life

Carbohydrates:

are a good source of sustained energy when they come in the form of polysaccharides. relative to fat or protein, are more quickly available as a source of fuel.

Which are examples of proximate perspective (as opposed to an ultimate/evolutionary perspective)? Selected Answers:

biochemistry how nausea can be caused by the inner ear physiology and anatomy

On food packages, "insoluble fiber" refers to plant material that we can't digest even though it is important for maintaining a healthy digestive tract. This substance is:

cellulose. carbohydrate.

The figure shows the mechanism of action of a beta-blocker drug in reducing anxiety. They work much like another drug studied in class, in that the drug binds to a cell surface receptor, preventing (blocking) the normal protein from binding and thereby exerting it's normal effect. A drug that works by this mechanism is known as a

competitive antagonist

Doctors, and even biologists, will loosely refer to pathogens or animals "developing" resistance to something (e.g., "bacteria are developing resistance to antibiotics"). What they actually mean is

evolving by natural selection

Read this brief article and answer the following questions about the article (not necessarily quotes) by filling in the correct information from the article exactly as it appears within the article (copy and paste to be safe; I can only specify one correct answer. For example, 5.5 is not the same as 5 1/2).

full anxiety, depression, physical health problems and - more than most students realize - academic troubles 6 1/2 nine Short different harm nothing

Which of the following are monosaccharides?

galactose glucose fructose

Lead is a teratogen (interferes with development). If individuals of one genotype are more sensitive to lead during development than those with a different genotype, this would be an example of:

gene-environment interaction

The complete set of an organisms DNA is called a ____ (one word, rhymes with "phone". Must be spelled correctly)

genome

The complementary base pairs in a DNA molecule are stabilized by:

hydrogen bonds

Water molecules form which type of bond with other water molecules?

hydrogen bonds

Using the first row as the reference, what kind of mutation occurred in the sequence in the 3rd row? A T G T G G C A T A T G G C A C A T A T G T G A C A T A T G G C A C A T A T G T G G C A T A A T G G C A C A

insertion in/del

Type 2 diabetes is a chronic disease in which the body cannot produce enough ________________, a chemical that allows cells to take up and break down sugar from the blood.

insulin

Caffeine:

is the most popular drug in the world. decreases one's ability to form memories. causes blood vessels to constrict and thereby increases the effectiveness of some pain killers (analgesics). causes an increase in the fraction of adenosine that is unbound to the adenosine receptor. habituation results in ever larger doses needed to achieve the same effect. is a competitive antagonist of adenosine. binds to a transmembrane receptor.

n humans, genes make up ______% of our DNA.

less than 5

What is the estimated heritability for longevity in LOG?

less than for most of the traits studied in this book

Tanning beds are

mutagenic carcinogenic

All non inherited (non congenital) forms of cancer results from

mutations in cells that undergo mitosis

When a biologist says that something "selects" or "favors" a trait, they mean:

natural selection

Mitosis results in:

new cells with the same number and composition of chromosomes

During eukaryotic translation, mRNA carries genetic information from the ________ to the ________, where amino acids are assembled into proteins.

nucleus; cytoplasm

The three nonsense codons that do not code for any amino acid, UAA, UAG, and UGA, are also known as:

stop codons

Cocaine was the active ingredient in Coca Cola until 1903. It remains one of the worlds most used illegal drugs and one of the most socially destructive drugs (deaths and costs associated with trafficking and use). What are some of the health effects of cocaine? Look these up at a relevant site (eg., medical, pharmacy/drug or encyclopedia) that should provide reliable information (eg., includes citation of peer-reviewed sources and does not rely on first person accounts/anecdotes).

stroke any drug not regulated by the FDA and sold through reputable dealers may contain contaminants, intentionally or otherwise. psychosis psychological disturbance (eg.,anxiety) high potential for addiction heart attack

Using the first row as the reference, what kind of mutation occurred in the sequence in the 2nd row? A T G T G G C A T A T G G C A C A T A T G T G A C A T A T G G C A C A T A T G T G G C A T A A T G G C A C A

substitution replacement

DNA is a macromolecule that stores information. Which component of DNA is the source of this information?

the base

Which of the following are always the same in every unit of the DNA molecule?

the sugar the phosphate group

Which are examples of ultimate perspectives?

why an illness like morning sickness might actually be beneficial with respect to reproductive success trade-offs between different selective pressures natural selection questions about the environment in which we evolved