CH. 3- HW Questions

Which is the correct term for compounds that do not mix with water?

DNA is composed of building blocks called _____.

DNA has the appearance of a _____. (What kind of helix?)

Which of the following statements regarding lactose tolerance is true? A) Relatively few people on this planet are lactose intolerant. B) The ability to hydrolyze lactose would be equally beneficial to all human populations. C) Lactose tolerance has evolved independently in multiple different human populations. D) Lactose intolerance refers to a person's inability to produce the sugar lactose.

When an RNA strand forms using DNA as a template, _____. (These are the pair-ups that result as an RNA strand forms from a DNA template.)

How many different kinds of amino acids are there in most proteins?

Which of the following best describes Alzheimer's disease? A) Alzheimer's only occurs in the elderly, and is expressed as shakes and tremors. B) Alzheimer's occurs most often in people under the age of 40. C) Alzheimer's only occurs in more developed countries, like the United States. D) Alzheimer's is a neurological disease with loss of memory and motor skills. E) Alzheimer's is caused by toxins in the environment, rather than through genetic inheritance.

Which of the following statements is FALSE regarding proteins? A) Alzheimer's disease causes proteins in the brain to become improperly folded. B) High heat and a change in pH can denature a protein. C) There is a link between improperly folded proteins and disease in both mad cow disease and Alzheimer's disease. D) The three-dimensional shape of a protein is critical for the functioning of that protein.

Why does the story in the video start in Columbia? A) There are no cases of inherited early onset Alzheimer's in Columbia, and researchers want to know what protects the population. B) There is an extended family with inherited Alzheimer's in Columbia, and researchers want to find the gene that causes it. C) There is an extended family with early onset Alzheimer's in Columbia, and researchers want to determine what environmental factor is causing it. D) There is an extended family with inherited early onset Alzheimer's in Columbia, and family members with the gene can be participants in a drug trial to reduce plaques.

According to the video, which of the following describes the impact of Alzheimer's in the United States by the year 2050? A) The incidence of Alzheimer's will likely decrease by 2050, as heart disease, stroke, cancer, and diabetes increase. B) Scientists are close to a cure for Alzheimer's, so the disease will be eradicated by 2050. C) It is projected that there will be 16 million cases by 2050, with an annual health care cost of $1 trillion. D) Almost everyone in the United States will have Alzheimer's by 2050.

Which of the following statements is correct? A) Alzheimer's disease causes beta-amyloid plaques to form in the brain. B) The presence of beta-amyloid plaques in the brain causes Alzheimer's disease. C) There is a correlation between beta-amyloid plaques and the severity of Alzheimer's disease. D) There is no correlation between beta-amyloid plaques and the severity of Alzheimer's disease.

Think about the experimental design of the drug trial described in the essay. Should everyone in the drug trial receive the drug being tested? A) Yes, because that is the only way to collect enough data to determine that the drug works. B) No, because there should be a control group that receives a placebo instead of the drug. C) No, because the drug might cause harm in some people. D) Yes, because that is the only humane way to conduct a drug trial.

Which of the following is a difficult ethical consideration in a drug trial like the one described here, and accurately describes Natasha's (Marta's daughter's) perspective in the video? A) Not everyone receiving a medication in a drug trial deserves the opportunity. B) It is unethical to test medications on humans until the medications are proven to be safe. C) Ethical standards require that all patients in a drug trial know if they are taking a placebo. D) Not everyone wants to know if they are carrying a gene that will eventually cause a horrible disease.

Your body contains tens of thousands of different proteins, each with a specific structure and function. The unique three-dimensional shape of each of these diverse proteins is based on several superimposed levels of structure. Which of the following statements is an accurate description of proteins? A) The primary structure of a protein is the order of amino acids in a polypeptide, as coded for in the DNA of a gene. B) The 20 amino acids found in proteins differ in the composition of their R groups, which may be either polar or charged. C) Secondary structures, which include the alpha helix or beta pleated sheet, are held together by interactions between R groups. D) Tertiary structure is the overall shape of a polypeptide, which may be stabilized by hydrophobic interactions, hydrogen bonds, ionic bonds, and peptide bonds. E) Quaternary structure is only found in proteins that have four identical polypeptide subunits.

What could happen if a mutation in a gene caused a hydrophobic amino acid in a polypeptide to be replaced by a hydrophilic amino acid? A) The hydrophilic amino acid could not form the proper peptide bond in its new location, so both the shape and function of the protein would be affected. B) There would be no effect as long as the protein had quaternary structure, because primary structure does not affect that level. C) The shape of the protein would not be affected if only one amino acid in the primary structure is changed. D) The new amino acid would not form the same interactions with hydrophobic R groups, and the protein's shape would likely be affected.

Which statement helps most to explain why life is based on carbon compounds? A) Each C atom makes three covalent bonds. B) C is very abundant in non-living nature. C) C makes strong bonds with O. D) C-C bonds are as strong as C-O bonds. E) All of the above.

DNA carries the instructions for building _____, and these instructions are found in informational units called _____.

A shortage of phosphorus in the soil would make it especially difficult for a plant to manufacture _____.

Which biological activity does NOT directly involve proteins? A) Breaking food polymers into smaller molecules. B) Sensing light. C) Changing the shape of a cell. D) Defending cells against viruses. E) None of the above; proteins are involved in all of them.

L-dopa is used to treat _____.

What kind of effect does R-dopa have on Parkinson's disease? A) At first it alleviates the symptoms but over the long term it makes the symptoms worse. B) None. C) At first it makes the symptoms worse but over the long term it alleviates the symptoms. D) It alleviates the symptoms. E) It makes the symptoms of Parkinson's disease worse.

Enantiomers are molecules that _____.

Geometric isomers are molecules that _____.

What are the three types of isomers?

Structural isomers are molecules that ____.

What do fats, steroids, and waxes have in common?

Dr. Haxton told one of his students, "To move in the bloodstream, fats need the help of phospholipids." What would a good student say? A) Right. Fats are too polar to travel alone in water. B) Yes. Nonpolar molecules aren't compatible with water. C) Not so. Fats are small enough to travel easily without help. D) Sorry, Dr. Haxton! Help comes from cholesterol, not phospholipids. E) You have it backwards. Fats help phospholipids to travel.

In a hydrolysis reaction, __________. In this process, water is __________.

Which of the following sugars CAN be accurately represented by the formula C6H12O6?

A carbon atom can form up to ___ covalent bonds.

What does cholesterol have in common with sex hormones?

For good health, you don't want your body to run the LDL part of this diagram faster than the HDL part because ...

Which of the following is the largest unit of DNA organization? A) gene B) nucleotide C) genome D) chromosome

A sugar, a phosphate, and a base are the components of a __________.

A page is to a book as a ___________ is to the genome.

How many polynucleotides are found in one molecule of DNA?

Which of the following make up the backbone of a polynucleotide strand? A) sugar only B) sugar and phosphate C) phosphate and base D) sugar and base

Dehydration reactions __________. They do so by __________.