Test 1 Prep (Ch. 1, 2, & 3) Flashcards
Which of the following statements about animal cell lipids is false?
Many lipids function as enzymes.
A single water molecule (H—O—H) is held together by
two polar covalent bonds.
The teeth of grain-eating animals (such as horses) are usually broad and ridged. This makes the teeth suitable for grinding and chewing. Meat-eating animals (such as lions) have pointed teeth that are good for puncturing and ripping flesh. This illustrates
a result of natural selection as well as the connection between form and function.
Water’s surface tension and heat storage capacity are accounted for by its
hydrogen bonds.
In a water molecule, hydrogen and oxygen are held together by a ________ bond.
polar covalent
The role of a control in an experiment is to
provide a basis of comparison to the experimental group.
Which of the following statements regarding matter is false?
All matter exists in the form of compounds.
Which of the following would be correctly classified as a protein?
an enzyme
Which of the following is an amino group?
-NH2
Which statement about bacteria is true?
Bacteria are in a domain of their own.
You notice that over the past month, many students on campus have started wearing a new style of school sweatshirt. You think to yourself that perhaps the bookstore has recently started selling this new sweatshirt style. This is an example of a(n)
hypothesis.
Which of the following statements about hydrocarbons is false?
Hydrocarbons are inorganic compounds.
Glucose molecules are to starch as ________ are to proteins.
amino acids
Which of the following statements regarding nucleotides is false?
Nucleotides contain lipids.
Which of the following statements about dehydration reactions is false?
Animal digestive systems utilize this process to break down food.
In plants, the process of photosynthesis produces glucose (C6H12O6) and oxygen from carbon dioxide and water. Which of the following options about photosynthesis is consistent with this statement?
All of the carbon atoms in glucose came from carbon dioxide.
A diet high in animal products and hydrogenated vegetable margarine may increase the risk for heart disease. This is because
most animal fats are saturated and many hydrogenated vegetable margarines contain high levels of trans fats.
What is the fundamental difference between covalent and ionic bonding?
In a covalent bond, the partners share a pair of electrons; in an ionic bond, one partner accepts electrons from the other.
Which sequence is not a correct pathway of energy through an ecosystem?
bacteria → plants → birds
Which of the following statements about the monomers and polymers found in living organisms is false?
Monomers are joined together by the process of hydrolysis.
Which of the following is dependent on the ability of water molecules to form hydrogen bonds with other molecules besides water?
the universality of water as a solvent
The tree in your backyard is home to two cardinals, a colony of ants, a wasp’s nest, two squirrels, and millions of bacteria. Together, all of these organisms represent a(n)
community.
Which statement about evolution is true?
Evolution can result in adaptations.
Which of the following particles are found in the nucleus of an atom?
protons and neutrons
Which statement provides the best evidence that there is a common genetic code that demonstrates the unity of life?
Through genetic engineering, a gene from a firefly can be inserted into a bacterium to make it glow.
Which of the following statements is not consistent with Darwin’s theory of natural selection?
Individual organisms experience genetic change during their life spans to better fit their environment.
Which of the following statements regarding triglyceride molecules is false?
Triglycerides are hydrophilic.
Which of the following is a carboxyl group?
-COOH
Which of the following statements regarding nucleotides is false?
Nucleotides contain lipids.
You have a cup of vegetable oil and a vial full of normal phospholipids. What would you predict would happen if you dropped the phospholipids into the cup of vegetable oil?
The phospholipids would form a sphere with the heads on the inside.
The hydrogen atoms of a water molecule are bonded to the oxygen atom by ________ bonds, whereas neighboring water molecules are held together by ________ bonds.
polar covalent; hydrogen
To be scientifically valid, a hypothesis must be
testable and falsifiable.
Table salt is formed when
sodium donates its single outer electron to chlorine.
What components make up a nucleotide?
a sugar, a nitrogenous base, and a phosphate group
Which statement about the properties of life is false?
Organisms have an unchanging, constant internal environment.
Which of the following is an example of secondary structure in a protein?
an alpha helix
Household ammonia has a pH of 12; household bleach has a pH of 13. Which of the following statements about these substances is true?
The ammonia has 10 times as many H+ ions as the bleach.
Which of the following statements about radioactive isotopes is true?
The energy emitted by radioactive isotopes can cause molecular damage in cells.
The tertiary structure of a polypeptide refers to
the overall three-dimensional structure.
The kingdom Fungi includes species
that obtain food by decomposing dead organisms and absorbing the nutrients.
What is the correct flow of information in gene expression?
DNA→RNA→protein
Mad cow disease serves as an example of how interdependent ________ and ________ are to protein.
structure; function
Which statement about ecosystems is false?
Bacteria and fungi recycle energy within an ecosystem.
Members of the kingdom Animalia
can obtain their food by eating other organisms.
A nutrition facts label from a fortified cereal states that in a single serving of cereal there is 8% of the percent daily value of the element phosphorous. The label also says that a single serving of cereal plus one-half cup of skim milk has 20% of the percent daily value of phosphorus. Which of the following statements is false?
A half-cup of skim milk contains twice as much phosphorus as a serving of cereal.
A major type of lipid found in cell membranes is
phospholipids.
________ are weak bonds that are not strong enough to hold atoms together to form molecules but are strong enough to form bonds within and around large molecules.
Hydrogen bonds
Electrons move about the nucleus of an atom in the same way that
insects fly around a bright lamp at night.
Which of the following statements regarding triglyceride molecules is false?
Triglycerides are hydrophilic.
A scientist performs a controlled experiment. This means that
two versions of the experiment are conducted, one differing from the other by only a single variable.
Which of the following organisms contain the polysaccharide chitin?
fungi and insects
Which statement about genetics is true?
Differences among organisms reflect different nucleotide sequences in their DNA.
An uncharged atom of boron has an atomic number of 5 and an atomic mass of 11. How many electrons does boron have?
5
Foods that are high in fiber are most likely derived from
plants
A theory is a(n)
explanation of an idea that is broad in scope and supported by a large body of evidence.
DNA differs from RNA because DNA
contains thymine in place of uracil.
Which of the following is a group within the domain Eukarya?
Fungi
The molecular formula of most monosaccharides represents a multiple of
CH2O.
Lactose intolerance is the inability to
digest lactose.
Radioactive isotopes
can be used in conjunction with PET scans to diagnose diseases.
In ocean acidification, dissolving CO2 gas ________ the pH of the ocean.
lowers
Which of the following statements regarding the oxygen atom of a water molecule is true?
Oxygen is more electronegative than the hydrogen atoms.
What feature of fats makes them hydrophobic?
Fats have nonpolar hydrocarbon chains.
What is the complementary sequence to the DNA strand TCGATGG?
AGCTACC
The role of a control in an experiment is to
provide a basis of comparison to the experimental group.
A buffer
donates H+ ions when conditions become too basic and accepts H+ ions when conditions become too acidic.
Basic science discoveries often lead to the development of technology, and the development of technology often leads to new scientific discoveries. Which of the following is not an accurate pairing of a technology and a discovery?
invention of the microscope and creation of evolutionary trees
Compared to a solution of pH 3, a solution of pH 1 is
100 times more acidic.
Structural proteins
are found in hair and tendons.
A phospholipid is composed of
one glycerol molecule linked to one phosphate group and two fatty acids.
Propanol and isopropanol are isomers. This means that they have
the same molecular formula but different chemical properties.
Which of the following statements about pH is true?
An increase in hydrogen ion concentration means a decrease in pH scale units.
Sucrose is formed
from two monosaccharides through dehydration reactions.
Organic compounds
always contain carbon.
Which of the following best describes the atomic number of an atom?
the number of protons in the atom
During a discussion about ecosystems, a student says, “Plants eat sunlight, and animals eat other organisms.” Which response to the student’s comment is most accurate?
Plants don’t eat sunlight; they use sunlight to make sugars.
Peptide bonds
link amino acids.
What is the general function of enzymes within a cell?
to speed up chemical reactions
Typically, nitrogen atoms are composed of electrons, protons, and neutrons. An isotope of nitrogen could
have more neutrons than the usual nitrogen atom.
The storage form of carbohydrates is ________ in animals and ________ in plants.
glycogen; starch
Which statement is not an example of evolution that has resulted from human activity?
Because of hunting, organisms such as bears and wolves are fewer in number.
Household ammonia, or ammonium hydroxide, is a mixture of ammonia (NH3) and water. What types of bonding interactions will occur between molecules of ammonia and water in a bottle of household ammonia?
hydrogen bonds between negatively charged nitrogen atoms in ammonia and positively charged hydrogen atoms in water
Fatty acids with double bonds between some of their carbons are said to be
unsaturated
In an ecosystem, energy
typically flows from producers to a series of consumers.
A protein containing more than one polypeptide chain exhibits the ________ level of protein structure.
quaternary
Which of the following statements regarding matter is false?
All matter exists in the form of compounds.
Proteins differ from one another because
the sequence of amino acids in the polypeptide chain differs from protein to protein.
Which of the following substances is made of lipids?
steroids
The sodium atom contains 11 electrons, 11 protons, and 12 neutrons. What is the mass number of sodium?
23
In the equation 2 H2 + O2 → 2 H2O, the H2 molecules are ________ and the H2O molecules are ________.
reactants; products
A radioactive isotope is an isotope that
decays.
A hydrogen atom has one electron. How many covalent bonds can hydrogen form?
one
Which of the following statements best describes a compound?
A compound contains two or more different elements in a fixed ratio.
Amino acids can be distinguished from one another by
the chemical properties of their R groups.
The tendency of water molecules to stick together is referred to as
cohesion
Which of the following lists contains only polysaccharides?
cellulose, starch, and glycogen
An antibiotic kills 99.9% of a bacterial population. You would expect the next generation of bacteria to
be more resistant to that antibiotic.
How are genes used by cells to build proteins?
The genes in DNA direct the synthesis of an RNA molecule, which is used to build a protein.
Which of the following trace elements needed by humans is commonly added to table salt?
iodine
Organisms belonging to the kingdom Plantae
are photosynthetic.
A hydroxyl group is
characteristic of alcohols.
Cellulose differs from starch in that
most animals cannot break down cellulose, whereas starch is easily digested.
Which of the following is a trace element in the human body?
Zinc
Which of the following organisms contain the polysaccharide chitin?
fungi and insects
The four most common elements in living organisms are
C, H, O, N.
The results of dehydration reactions can be reversed by
hydrolysis reactions.
Which statement best describes the relationship between a tissue and an organ system?
An organ system includes tissues.
Which statement about ecosystems is false?
Energy cycles from organisms through the atmosphere and back to the organisms.
A disaccharide forms when
two monosaccharides join by dehydration reactions.
A(n) ________ forms when two atoms share electrons.
covalent bond
How will a lower ocean pH caused by ocean acidification affect coral reefs?
Coral reefs will grow slower because there are fewer carbonate ions available.
Which of the following statements about the functional groups of organic compounds is false?
All functional groups include a carbon atom.
If you found a fossilized dinosaur bone, what could be done to accurately determine the age of the fossil?
Analyze the isotopes of carbon in the fossil.
Life is organized in a hierarchical fashion. Which sequence correctly lists that hierarchy from least inclusive to most inclusive?
molecule, organelle, cell, tissue, organ, organ system, organism, population, community, ecosystem
Your textbook describes experiments concerning predation of mice that belong to the same species but live in two different habitats. The mice in the two habitats were differently colored. How were these experiments carried out?
Plastic models of mice of the two different colors were placed in each habitat, and the frequency of predator attacks was recorded.
When all the available evidence was taken into account, scientists concluded that the red panda, which has characteristics similar to those of bears, raccoons, weasels, giant pandas, and other bears, belongs to __________.
the family Ailuridae, of which it is the only member
What do you predict would occur if a gene for manufacturing insulin were inserted into the DNA of bacterial cells growing in the laboratory?
The cells would manufacture insulin.
Select the correct statements regarding the transfer and transformation of energy and matter in ecosystems.
Energy enters most ecosystems as light and exits as heat.
Consumers use the energy and matter in food to build new molecules.
Decomposers are critical for the cycling of matter in ecosystems.
Darwin used many lines of evidence to show that natural selection is the mechanism of evolution. One line was the overproduction of offspring in animal species. How did Darwin believe that this affected natural selection?
It created the need for competition for resources such that only the best-adapted individuals would survive to reproduce.
In most ecosystems, __________ energy is converted into __________ energy by __________.
light; chemical; producers
In the section in your textbook about systems biology, interactions among members of the bacteria-sloth-tree system in the South American rain forest were described. What benefit do these South American sloths derive from the bacteria that live on their hair?
The greenish-brown coat provides camouflage from predators.
Darwin posited that the mechanism for evolution is __________.
natural selection
After a person eats dinner, which of the following occurs?
The concentration of glucose in the blood increases, causing the pancreas to release insulin, which allows glucose to enter cells, thereby lowering blood glucose levels.
What effect does “unequal reproductive success,” one of Darwin’s inferences regarding evolution, have on a population over time?
Individuals whose inherited traits best allow them to survive and reproduce will make up an increasingly greater proportion of the population.
Robins, blue jays, and sparrows live in your garden, which is also filled with roses, tulips, and wisteria. Which of the following statements correctly uses the terms of life’s hierarchy of organization with relation to your garden?
There are robin, blue jay, and rose populations in your garden community.
You found a new single-celled organism and wish to demonstrate that it is a living thing. You take the organism back to the lab and monitor it for several days, recording your observations. Select the observation that would indicate that this organism is truly alive.
The organism grows, divides, and produces more single-celled organisms like itself.
When you shade part of the slide, the organism moves toward the light using a tail-like appendage.
Your text contains this sentence: “Every citizen has a responsibility to develop a reasonable amount of scientific literacy to be able to participate in the debates regarding science, technology, and society.” What does this mean?
People ought to understand science well enough to be able to understand how it, technology, and society can address complex problems.
Which of the following is a correct statement comparing the “false thumbs” of this red panda and the giant panda?
The structures are anatomically similar but evolved separately in the two lineages.
Which of the following correctly lists the main steps in the flow of information from gene to protein?
A segment of DNA is transcribed to RNA, which is then translated into a chain of molecules that make up a protein.
Which of the following INCORRECTLY pairs a listed organism and its domain?
An organism living in a boiling hot spring belongs to the domain Bacteria.
Your new plant, which stood straight and tall when you brought it home from the store a few weeks ago, is now bending slightly and has its leaves turned toward the sunlight streaming into your dining room window. This is an example of which characteristic of living things?
Response to the environment
To qualify as a scientific hypothesis, a proposed explanation for a set of observations must be __________.
testable
Which of the following questions could be answered by a retrospective study that tests a hypothesis?
Was radiation therapy for breast cancer more effective in patients treated at Hospital A than at Hospital B?
Which of the following choices shows the correct arrangement of the components of life’s hierarchy of organization, going from smallest to largest?
A. Population
B. Cell
C. Organ
D. Organ system
E. Biosphere
F. Tissue
G. Community
H. Organelle
I. Organism
J. Molecule
K. Ecosystem
CORRECT ANSWER:
J, H, B, F, C, D, I, A, G, K, E
Let’s imagine there are two species of squirrels, Chattery and Squeaky, in the same habitat. Chattery squirrels can digest pine nuts from pine trees and acorns from oak trees, whereas Squeaky squirrels can digest only acorns. Chattery squirrels are small and timid, while Squeaky squirrels are large and aggressive. One summer, a disease kills off all of the oak trees. What does natural selection predict will happen?
Over time, Chattery squirrels will outnumber Squeaky squirrels because they are better adapted to the environment’s new, more limited food supply.
A researcher hypothesizes that mice who eat spinach will develop stronger hamstring muscles. To test her hypothesis, she feeds one group of mice their regular diet plus spinach, and a second group of mice their regular diet only. Both groups have access to running wheels in their cages. After 6 weeks, she tests the strength of the hamstrings in all of the mice. Which of the following correctly describes this experiment?
This is a controlled study in which the independent variable is spinach and the dependent variable is hamstring strength.
Which of the following is present in a controlled clinical trial, but lacking in a retrospective study, of a new drug (“X”) that might be effective in treating tuberculosis?
A placebo drug
Which of the following is an example of natural selection?
Black beetles, which are vulnerable to extreme cold, vanish from the region during one very cold winter in Montana.
Biologists rely heavily on feedback from their __________ in refining and improving their hypotheses.
peers
What information is provided by a molecule’s structural formula that is not provided by its molecular formula?
number of covalent bonds and whether they are single, double, or triple
Which of the following is a characteristic of Carbon-14, but not of Carbon-12 or Carbon-13?
Its nucleus is unstable.
In a covalent bond, electrons are __________. In an ionic bond, electrons are __________. Which is the stronger type of bond?
shared; transferred; covalent
Scientists have found several lines of evidence pointing to the existence of water on Mars. Which of the following have they observed?
ice caps at both poles
soil samples containing water
In Sweden (a cold country) one year, there was sunshine from July 1 to July 10, followed by several days of very cold, rainy weather. If you wanted to stay warm that year during your late-July camping trip, where was the best place to pitch your tent? Why?
Near the coast: Water stores heat from the sun and releases it gradually.
A radioactive tracer called PIB can be used to detect beta-amyloid plaques in the brains of some people with Alzheimer’s disease. This represents the medical use of radioactive isotopes to __________.
diagnose disease
Which of the following is not a true statement regarding radioactive isotopes?
They can be used to diagnose, but not to treat, certain diseases.
Which of the following is the best definition of a polar molecule?
a molecule with an unequal distribution of charges
Which of the following is a disease caused by an excess of a trace element and what is the element?
fluorosis; fluoride
Water has different properties from its components hydrogen and oxygen. Such properties are called __________.
emergent
Which of the following are the reactants in the chemical reaction that results in 2 molecules of water (2H2O)?
2 molecules of hydrogen gas and 1 molecule of oxygen gas
What happens when water is heated?
Hydrogen bonds are broken.
The cells of the human body are about __________% water. Six elements together make up about 99% of the body. These are oxygen, carbon, hydrogen, __________, __________, and __________.
70; nitrogen; calcium; phosphorus
Little Freddie is a bored child at home on a rainy day. He stirs sugar into his water until it dissolves. Match the components of Freddie’s new “drink” to their appropriate chemistry terms.
solute–sugar
solvent–water
solution–sugar and water mixture
A deficiency of __________ is the world’s most common nutritional deficit.
iron
An atom’s mass number equals which of the following?
number of protons + number of neutrons
Which subatomic particles are directly involved in an atom’s chemical activity?
electrons
The atomic number of neutral sulfur = 16. How many electrons does a sulfur atom have in its valence shell?
six
Sodium chloride (NaCl, table salt) is a compound but not a molecule. Why?
It does not contain covalent bonds.
What is radon?
A radioactive gas from the decay of uranium that can cause lung cancer
Of what substance are coral reefs mainly composed?
calcium carbonate skeletons of coral animals
The process whereby coral animals form their skeletons is called __________.
calcification
Hydrogen and helium are the only elements in the first row of the periodic table. What characteristic(s) do they share that determine(s) their position?
They have only one electron shell.
Drinking a buffering solution, such as milk of magnesia, after eating a very acidic meal would be likely to have which of the following effects on the pH of a person’s stomach contents?
The pH would increase.
Which of the following could alter or destroy the function of a protein?
a genetic mutation that changes the amino acid sequence
excessive heat
moving a protein that functions in a neutral environment to an acidic solution
placing a protein that functions in an acidic environment into a neutral solution
Which of the following is the best description of “R” groups of an amino acid?
carbon atoms with different functional groups attached
Here is a partial list of substances found in living cells. Which, if any, of these substances is not a macromolecule?
lipids
When comparing DNA and RNA, only one of these choices is correct. Which one?
DNA directs the synthesis of RNA, which is used to synthesize protein.
When you eat a piece of cheese, which of the following occurs for you to break down the polymers in the cheese and then rebuild them into polymers you need in your cells?
hydrolysis, then dehydration
Cellulose is a __________ made of many __________ linked together with __________ bonds.
polymer; glucose molecules; covalent
Lactose intolerance appears to be the “norm” for humans, yet many Northern Europeans happily consume large quantities of milk and cheese. Which of the following probably led to the high prevalence of lactase in Northern Europeans?
The cold climate of Northern Europe likely forced people to rely on dairy products.
Your apartment has a cockroach problem. When you walk across your kitchen floor late at night, you hear “CRUNCH, CRUNCH” as you trample on an army of cockroaches. What substance in the insects’ bodies produces that sound, and to what category of polysaccharide does it belong?
chitin; structural polysaccharide
The average American consumes approximately __________ times the amount of sugar recommended by the World Health Organization.
six
Fatty acids, unsaturated fats, saturated fats, and cholesterol are alike in which of the following ways?
They do not mix well with water.
Which of the following statements is correct regarding double-layered cell membranes?
The phosphate-glycerol heads face the watery environment.
Why are the two strands of DNA called “complementary”?
The base sequence of one strand exactly predicts the base sequence of the other.
Which of the following statements about carbon skeletons is correct?
Carbon skeletons can be straight or in the shape of a ring.
The backbone of protein molecules coils or folds into local patterns. This gives the protein its __________ structure. A protein composed of more than one polypeptide chain has a __________ structure.
secondary; quaternary
Which component of the core structure of an amino acid makes the molecule acidic?
carboxyl group
In hydrolysis, which of the following occurs?
A polymer is broken down by the addition of water; water is consumed.
Here is the chemical formula for glucose: C6H12O6. Maltose is a disaccharide formed when two glucose molecules combine via a dehydration reaction. Using this information, determine the chemical formula of maltose.
C12H22O11
Match the following protein types with their function.
Match the following protein types with their function.
CORRECT ANSWER:
speed up chemical reactions–enzymes
provide nutrients–storage proteins
move materials into–transport proteins
Sucrose, the most common disaccharide, is made of a __________ molecule joined to a __________ molecule by means of a __________ reaction.
glucose; fructose; dehydration
The “building blocks” of the nucleic acids DNA and RNA are called __________. These building blocks are __________.
nucleotides; monomers
Which is the correct sequence of events in gene expression?
DNA→RNA→protein
Which functional group can transfer energy among organic molecules?
phosphate
Which of the following side effects is not linked to anabolic steroid use?
improvement in mood
In chemistry, an “organic” compound is a compound with which of the following characteristics?
It always contains carbon atoms.
According to the long-term Nurses’ Health Study, which of the following foods is associated with the lowest relative risk of heart disease?
polyunsaturated fats
