Biology Chapter 5-8
Which of the following pieces of critical information did Watson and Crick use to build and propose their model of the structure of DNA?
%A always equals %T and %G always equals %C x-ray diffraction images that suggest DNA is hydrophilic and elongates upon exposure to water x-ray diffraction images that show DNA as a double helix an incorrect model that depicts DNA as a triple helix with the phosphate groups on the inside
Complete the following statements regarding the steps necessary to copy a DNA sequence during PCR: 1) The two original strands of the DNA molecule can be separated by _____. 2) The enzyme _____ "reads" each template strand and adds _____ to make a new strand.
1) heat, 2) DNA polymerase; complementary nucleotides
How many STRs are typically used to create a profile in forensic investigations?
15
The _____ chromosomes in a human cell from inside the cheek are found in the _____.
46; nucleus
If you start with one copy of a DNA fragment, how many rounds of PCR will it take to end up with a total of 32 copies?
5
Which statement accurately describes food with regard to energy?
A food Calorie is equal to 1,000 calories.
Which statement accurately describes how genes, chromosomes, and proteins are related?
A gene on a chromosome encodes a protein.
Select examples of energy changing forms. Select the THREE answers that are correct
A green plant absorbs light to make sugar molecules. From a high perch, a raptor dives toward its prey. A human jogs down the street for exercise.
You are investigating a crime. The DNA profile database has no perfect matches to the DNA collected at the crime scene. However, one profile in the database has at least one band in common with the crime scene DNA at every STR site. Which statement is the most likely conclusion can you draw?
A parent-child relationship exists between the DNA collected at the crime scene and the DNA in the database
Researchers create a transgenic organism by inserting a gene from algae into corn. How do researchers make the algae gene function in corn?
A regulatory sequence from corn DNA is joined to the coding sequence of the algae gene, and the resulting recombinant gene is inserted into the DNA of the corn
How do the environmental costs of growing algae for biofuel production compare to other crop options?
Algae require less fertilizer than corn.
What is a possible consequence of a mutation affecting a nucleotide in a coding sequence of an mRNA molecule?
An incorrect amino acid is added to the growing chain, resulting in a defective protein that potentially does not function properly.
_________ can directly use the energy of sunlight to make their own food, and ______ must rely on other organisms to provide the energy they need to survive.
Autotrophs; heterotrophs
Select the statements that correctly describe how a new DNA molecule reflects the original DNA molecule from which it was copied.
Base pairing rules duplicate the base pairs of the original molecule in the new molecule. Each new DNA molecule contains an original strand and a newly synthesized strand.
Why are biotechnology companies eager to design genetically modified organisms to express therapeutic proteins, particularly ones that would otherwise have to be isolated from blood products (e.g., human antithrombin) or animal organs (e.g., insulin, originally isolated from pig pancreas)?
Biotechnology companies are interested in the cost-effectiveness, safety, and efficiency of protein production.
You can detect DNA that is specifically from the X chromosome in a DNA sample from a person. Why can't you definitively determine the sex of that person (male or female) from the presence of the X chromosome?
Both males and females have an X chromosome and you would have to check for the presence of a Y chromosome.
If you ingest carbon in the form of sugar, then that carbon is released from your body as _____.
CO2
What roles do atmospheric gases have in photosynthesis?
Carbon dioxide is a reactant for photosynthesis that provides the carbon in glucose. Oxygen is produced from water during the light-gathering phase of photosynthesis.
Which statement accurately summarizes the process of photosynthesis?
Chloroplasts capture sunlight, water is split, oxygen is released, and carbon dioxide is used to convert chemical energy into glucose.
_____ on mRNA interact with _____ on tRNA to allow the _____ to connect amino acids in the correct order during translation.
Codons; anticodons; ribosome
Where is the information for building proteins encoded?
DNA
Each chromosome contains _____
DNA and proteins.
Why does DNA travel toward the positive electrode during gel electrophoresis?
DNA is negatively charged, and opposite charges attract.
Why is DNA replication called "semiconservative"?
DNA is replicated, each copy having one strand of the original molecule and one newly synthesized strand
How is DNA stored in eukaryotic cells?
DNA is sequestered in the nucleus apart from the metabolic activity of the cytoplasm. DNA is a linear molecule wrapped around proteins and condensed into chromosomes
Which statement about PCR is true?
DNA polymerase is the enzyme that copies DNA in PCR.
What naturally occurring process does PCR mimic in a test tube?
DNA replication
hy can the same short tandem repeat region vary in length between the two copies of a chromosome of an individual?
Each chromosome is inherited from a different parent.
Which statement best summarizes the law of conservation of energy?
Energy changes forms and is neither created nor destroyed.
If you frequently crave French fries, how could you modify your lifestyle to eat fries without gaining weight?
Exercise more to burn more calories than the fries you add to your diet.
In humans, why can't fermentation sustain life?
Fermentation is not efficient at using the energy sources we eat to make ATP.
Which STR will have migrated farthest through an electrophoresis gel?
GAAG repeated twice
Select the statement that best describes the function of heating and cooling in PCR.
Heating facilitates strand denaturation, and cooling facilitates primer attachment
What would happen if algae, cyanobacteria, and plants were wiped out?
Heterotrophs would not be able to use autotrophs as an energy source
_____amino acids tend to be found folded inside a protein, whereas _____ amino acids interact with water on the outside of the protein.
Hydrophobic; hydrophilic
Which sequence correctly describes the input (I) and output (O) of photosynthesis.
I - carbon dioxide, photons, water; O - oxygen, glucose
A moderately active 21-year-old female has a choice of eating a 2,500-Calorie meal that is primarily protein or a 2,500-Calorie meal that is primarily sugar. What would be the result, in terms of energy, of choosing one over the other?
In either case, once her glycogen stores are replenished, she will store the excess calories as fat.
Why did searching for unique algae species open new opportunities for their use as a biofuel?
It can make the process independent of sunlight.
Under aerobic conditions, when is pyruvate produced and consumed?
It is produced in glycolysis and consumed in the citric acid cycle
Chargaff discovered that the A-T bond has the same width as the G-C bond. What implication does this have for the structure of the DNA molecule?
It means that the molecule will vary in width as you move down its length, depending on the number of A-T and G-C nucleotides.
Why is photosynthesis important to both plants and animals?
It produces glucose. It produces oxygen
During aerobic respiration, what molecule holds and carries electrons stripped from food?
NADH
Human red blood cells are enucleated (i.e., they do not have nuclei). Is it possible to isolate DNA from red blood cells? Why or why not?
No, the genomic DNA is found only in nucleated cells.
Select the statements that best describe how nucleotides pair with one another in a DNA molecule
Nucleotides pair with each other, joining two strands of DNA by hydrogen bonding. Adenine pairs with thymine, and guanine pairs with cytosine.
Why do leaves appear in shades of yellow, orange, and red in the fall?
Other leaf pigments that were masked by the chlorophyll become visible and reflect wavelengths of light other than green.
What is the polymerase chain reaction (PCR)?
PCR produces many copies of a DNA sequence from a small sample using temperature cycling, primers, free nucleotides, and polymerase enzymes
Photosynthesis can be broken down into two basic mechanisms (photo and synthesis). Which sequence describes these two mechanisms?
Photo - absorption of light; Synthesis - carbon fixation
How would an anaerobic environment affect photosynthesis?
Photosynthesis would continue, assuming there was also sufficient light, water, and carbon dioxide
What is the purpose of careful primer design before PCR?
Primers indicate the section of DNA that will be amplified and mark where DNA polymerase begins replication.
Identify the true statements about wavelengths of light.
Red light has a longer wavelength and less energy than blue light. Plants reflect wavelengths of light that our eyes cannot detect.
Type 1 diabetes results from a loss of insulin production from the pancreas. People with diabetes take recombinant human insulin expressed in bacteria. How would you cure the disease instead of treating it?
Replacing the defective insulin gene in a patient through gene therapy would allow for a cure.
Which statement about genetically modified organisms is true?
Scientists can produce more complex proteins made by eukaryotes by genetically modifying eukaryotic cells instead of prokaryotic cells.
How do the redundant properties of the genetic code protect humans from some mutations (changes in the gene sequence)?
Some mutations will not change the amino acid coded by the mRNA codon.
If the sequence of one strand of DNA is AGTCTAGC, what is the sequence of the complementary strand?
TCAGATCG
Rosalind Franklin used x-ray diffraction to record how x-rays scatter when bounced off the surface of DNA molecules. Which of the following conclusions about the structure of DNA did her images support?
The DNA helix was likely made of two strands. The DNA molecule was likely helical. The DNA molecule was hydrophilic and extends upon exposure to water. The DNA molecule was uniform in width.
If the French eat meals with a higher fat content, what might explain why the French weigh less on average than Americans?
The French engage in more NEAT activities such as household chores, shopping, and dog walking
What role does carbon dioxide play in photosynthesis?
The carbon in carbon dioxide is incorporated into sugar molecules.
Which statement correctly reflects the interactions between aerobic respiration and photosynthesis?
The carbon in the glucose that plants make is the same carbon in the carbon dioxide we breathe out
Why does anaerobic respiration yield less energy than aerobic respiration?
The citric acid cycle and electron transport are not used in anaerobic respiration.
Why is it recommended that anyone trying to lose weight should avoid alcoholic beverages?
The fermentation process used to make alcohol does not fully break down glucose, resulting in a high-carbohydrate beverage.
Melanin is a pigment expressed in skin cells; melanin gives skin its color. If you wanted to express a different gene in skin cells, which part of the melanin gene would you use and why?
The melanin regulatory region would allow for the specific expression of a different gene in the skin.
What happens to plants in the absence of light?
The process of photosynthesis shuts down Plants stop generating chemical energy from light.
Heating a protein can cause it to denature, or unfold. What do you think would happen to the function of a protein in a denatured state?
The protein would not be functional because the three-dimensional shape dictates protein's function.
Why are energy-rich lipids from algae more useful as a fuel than energy-rich sugars and other carbohydrates produced by photosynthetic organisms such as corn and wheat?
The sugars contain less chemical energy than the lipids and the lipids can be used directly as fuel
Identify the statement that correctly describes what happens at the end of transcription.
The synthesized mRNA molecule leaves the nucleus and enters the cytoplasm.
Why are algae considered more valuable for biofuel than plants (such as corn)?
They are cheaper to grow.
Which statement accurately describes amino acid side chains?
They provide unique functions and allow for the correct folding of proteins
Similar to the process of transcription, tRNA molecules bring amino acids to mRNA molecules during translation using base-pairing rules. Identify the anticodons that match the mRNA sequence AUGUCAUGGACU.
UAC, AGU, ACC, and UGA
A gene has the sequence ATCGATTG. What is the sequence of the complementary RNA?
UAGCUAAC
A DNA sequence reads ATCAGCTA. Select the mRNA sequence that would correspond with this DNA sequence.
UAGUCGAU
What role does water play in photosynthesis?
Water provides hydrogen and electrons used in producing glucose
Which of the following scientists is incorrectly paired with their contribution to the discovery of the structure of DNA?
Watson and Crick; x-ray diffraction images of DNA helix
From the STRs used in a forensic investigation, which STRs on which chromosomes would be particularly useful in determining whether crime scene evidence was left by a female or a male?
Y chromosome STR
Select the best description of a short tandem repeat.
a nucleotide sequence of at least two bases that is continuously repeated in a DNA strand
What is the final product of gene expression?
a protein
In the presence of oxygen, humans use _____ to fuel ATP production from glucose, Glucose is initially formed by plants through _____.
aerobic respiration; photosynthesis
A protein is made up of a chain of _____
amino acids
Which statement describes the ways that photosynthetic algae and animals obtain energy?
animals obtain energy from sugar made by light-absorbing energy producers.
What is a genetically modified organism?
any modified organism that produces a product it does not normally make.
Recombinant protein production of spider silk in yeast is an efficient strategy because yeast _____
are easier to house and less expensive to feed than multicellular organisms.
Photons are critical to the process of photosynthesis because photons _____.
are needed to excite the electrons of the pigment atoms in chlorophyll
What are the functions of the protein ends of spidroin?
assembly into silk-fibers
How were researchers able to produce silk from algae?
by inserting the silk gene into the DNA of algae for expression
What products of aerobic respiration are used in photosynthesis?
carbon dioxide water
What energy source drives the carbon fixation process of photosynthesis, and where does it come from?
chemical energy from light absorption stored in ATP
Which sequence correctly traces the flow of energy needed to move an automobile?
chemical energy; heat energy; kinetic energy
The energy in a cereal bar is _____ energy. The energy of a cyclist pedaling is _____ energy.
chemical; kinetic
what organelle does an algae need to be able to conduct photosynthesis?
chloroplast
Scientists altered the gene for spidroin so that it could be isolated from yeast by attaching the _____.
coding sequence of a spider spidroin gene to a yeast regulatory sequence
Identify the part of the mRNA molecule and tRNA molecules that correspond with one another in translation.
codon and anticodon
Each time energy is converted from one form to another, a percentage of that energy is lost as _____ or fails to be converted.
combustion
The purpose of aerobic respiration is to _____, which is used to _____.
create energy-rich ATP molecules; power functions of the cell
Which of these are photosynthetic organisms?
cyanobacteria and plants
Where in the cell does fermentation take place?
cytoplasm
You are studying the DNA profile of an individual, and you are looking at the results for a chromosome with just one STR site. How many bands will you see?
either 1 or 2
What stage of aerobic respiration produces the most ATP?
electron transport
What process(es) is(are) most directly prevented in the absence of adequate oxygen?
electron transport chain
DNA evidence can give an investigator information regarding which of the following?
family relationships between suspects and the identity of an individual based on a profile
Which type of organic molecule stores the most energy per gram?
fats
Which of these photon wavelengths contains the greatest amount of energy?
gamma rays
The entire sequence of DNA in a cell used for DNA profiling is called the _____.
genome
What molecule provides short-term energy storage in the body?
glycogen
If you exercise for an extended period of time, you will use energy first from _____, then from _____
glycogen; fats
Excess energy can be stored for short periods of time in the muscle and liver tissue as _____, and for long periods of time as _____ in fat cells
glycogen; triglycerides
Which process is correctly matched with its cellular location?
glycolysis—cytoplasm
What chemical interactions determine how a protein folds?
interactions among core structures of amino acids interactions among side chains of amino acids interactions between amino acid side chains and water
Fermentation in animals produces _____, whereas fermentation in brewer's yeast produces _____.
lactic acid; alcohol
What factor does gel electrophoresis use to separate DNA molecules?
length of individual DNA molecules
What cellular machinery is involved in translation?
mRNA ribosome
_____is the product of transcription, and _____ is the product of translation.
mRNA; a protein
Glucose is a product of photosynthesis. Where do the carbon atoms of glucose produced during photosynthesis come from?
molecules in air
Compared to aerobic respiration, fermentation produces _____ ATP.
much less
Which of these does NOT contribute to a higher BMI?
nonexercise activity thermogenesis
An individual's STR may vary from the same STR of another individual by the _____
number of times a particular sequence is repeated.
DNA replication is said to be semiconservative because a newly replicated, double-stranded DNA molecules consists of _____.
one old strand and one new strand
In addition to the base, what are the other components of a nucleotide?
phosphate and sugar
The energy of sunlight exists in the form of _____.
photons
The fuel used to run our cars contains _____ energy.
potential
During fermentation, NADH gives up electrons to regenerate NAD by giving electrons to _____.
pyruvate
A person can be deficient in the production of a protein if he or she has a mutation in the:
regulatory region or the coding region of a gene.
The _____ control(s) the timing of gene expression.
regulatory sequence for a gene
Rosalind Franklin did not receive the credit she deserves for her contribution to the discovery of the structure of DNA because _____.
she died before the Nobel Prize was awarded to Watson, Crick, and Wilkins None of the answers is correct. her paper was perceived merely as supporting evidence for Watson and Crick's model. at the time, prevailing attitudes were negative toward women in science
Gel electrophoresis separates DNA for profiling based on the _____.
size (length)
In a spider silk producing transgenic yeast, the _____.
spider silk coding sequence is joined with a yeast regulatory sequence.
What is the function of DNA?
stores chemically coded, heritable information in an organism
If a person wants to lose weight, which of these is a viable strategy?
substituting plain water for regular soda and exercising more
Select the parts that make up the backbone of the DNA molecule.
sugar phosphate
Which statement correctly indicates a functional location during gene expression?
tRNAs work in the cytoplasm.
Once excess calories are stored as triglycerides, it is more difficult to release this energy because _____.
the body utilizes food molecules in the bloodstream and stored glycogen first
What bonds in an ATP molecule store the chemical energy used by cells?
the bonds between phosphates
Why do many species of algae appear green?
the chlorophyll pigment they contain is green
Which of these parts of translation will be disrupted by a mutation in the coding region of a gene?
the codon on the mRNA
During aerobic respiration, NADH gives up electrons to regenerate NAD by giving electrons to _____.
the electron transport chain
Kinetic energy is best described as _____.
the energy of movement
Which of these does NOT play a role in determining the three-dimensional shape of a protein?
the interaction of the genes that lie next to a protein gene
Which factor is NOT driving our search for alternative fuel sources?
the large amount of water and pesticides used when biodiesel is produced from corn
Which phrase represents genetic variation between individuals?
the number of STRs in their genomes
What determines a protein's function?
the three-dimensional shape of the folded protein
Imagine that you have discovered a new species that has the ability to consume other organisms for energy and also contains chloroplasts. What would these properties tell you about the organism?
this organism is both heterotroph and an autotroph
What is the role of pyruvate under anaerobic conditions?
to generate ATP and lactic acid to produce NAD+ from NADH
What roles does the circulatory system play in aerobic cellular respiration?
transport glucose from the digestive system to body tissues transport oxygen to body tissues and carbon dioxide to the lungs
What molecule provides long-term energy storage in the body?
triglyceride
Which of these is NOT a nucleotide found in DNA?
uracil (U)
When considering which biofuel is the most sustainable, which of these must be considered?
water, energy, and fertilizer and pesticide use
What do plants obtain from soil?
water; nutrients
What two factors determine the BMI for an individual?
weight and height
Which person would have DNA that is least similar to yours?
your mother's brother
