Biology 101 Final Exam
All of the following are true of all living organisms EXCEPT that they
Possess either DNA or RNA
Which of the following is NOT an organic molecule?
Carbon monoxide
In the plasma membrane, the phospholipid heads
Are hydrophilic and face outward toward the aqueous solution on both sides of the membrane.
Organisms belonging to the kingdom Plantae
Are photosynthetic.
Organic compounds
Always contain carbon
Identify the molecule shown below:
Phospholipid
Which of the following is an amino group?
-NH2
Which of the following is a group within the domain Eukarya?
Fungi
Which of the following is a carboxyl group?
-COOH
The sodium atom contains 11 electrons, 11 protons, and 12 neutrons. What is the mass number of sodium?
23
When full, the innermost electron shell of argon contains __________ electrons, and the outermost shell contains __________ electrons.
2; 8
An uncharged atom of Boron has an atomic number of 5 and an atomic mass of 11. How many electrons does Boron have?
5
Which is NOT an example of evolution?
A dog learning how to open the cabinet where its food is kept.
A scientist wants to examine living cells lining the respiratory tract to determine how the cells use tiny hairs to move dirt and mucus away from the lungs. Which of the following instruments would be best, and why?
A light microscope, because it allows observations of whole, live cells
A hypothesis is
A proposed explanation for a set of observations
What components make up a nucleotide?
A sugar, a nitrogenous base, and a phosphate group
An oil may be converted into a substance that is solid at room temperature by
Adding hydrogens, decreasing the number of double bonds in the molecules
Glucose molecules are to starch as __________ are to proteins.
Amino acids
Which statement best describes the relationship between a tissue and an organ system?
An organ system includes tissues.
Which of the following statements about dehydration reactions is FALSE?
Animal digestive systems utilize this process to break down food.
Which statement about bacteria is TRUE?
Bacteria are in a domain of their own.
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.
Members of the kingdom Animalia
Can obtain their food by eating other organisms
Which of the following does NOT describe quaternary protein structure?
Can occur with a single protein molecule
A molecule with the formula C12H22O11 is what kind of molecule?
Carbohydrate
Which of the following statements regarding carbon is FALSE?
Carbon has the ability to bond with up to six other atoms.
The four most common elements in living organisms are
Carbon, Hydrogen, Oxygen, and Nitrogen
A peptide bond forms between which of these groups?
Carboxyl and amino
A scanning electron microscope is used to study __________, whereas a transmission electron microscope is used to study __________.
Cell surface; Internal cell structures
Which is the correct sequence of increasing organization?
Cell, tissue, organ, organ system
A mutation is a
Change in the DNA sequence
What change is occurring in this figure?
Chlorine is filling its third electron shell.
The tendency of water molecules to stick together is referred to as
Cohesion
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 of these is NOT scientific?
Consumers are asked which tomato variety produces the best-tasting spaghetti sauce.
The nucleus of a cell
Contains DNA
DNA differs from RNA because DNA
Contains thymine in place of uracil
Which statement about genetics is TRUE?
Differences among organisms reflect different nucleotide sequences in their DNA.
Which of the following best summarizes the relationship between dehydration reactions and hydrolysis?
Dehydration reactions assemble polymers, and hydrolysis breaks them down.
Your friend is trying to learn about how to kill bacteria. She reads that preservatives such as citric acid are added to foods because the acidic environment kills bacteria by denaturing their proteins. She thinks this sounds like a lot of scientific jargon and asks you what it means. How can you explain it in simpler terms?
Denaturing means that the proteins of the bacteria lose their structure and can't function, so the bacteria die.
Identify the molecule shown below:
Disaccharide
A buffer
Donates H+ ions when conditions become too basic and accepts H+ ions when conditions become too acidic
Polar covalent bonds form when
Electrons are shared unequally between atoms
Which statement about evolution is TRUE?
Evolution can result in adaptations.
A theory is a(n)
Explanation of an idea that is broad in scope and supported by a large body of experience.
The temperature of evaporation is much higher for water than for alcohol. Without knowing more about the chemistry of alcohol, which of the following is the most logical chemical explanation for this phenomenon?
Fewer hydrogen bonds form between alcohol molecules. As a result, less heat is needed for alcohol molecules to break away from solution and enter the air.
Water molecules are cohesive because they
Form hydrogen bonds
The formation of ions involves the
Gain or loss of electrons
Evolution is sometimes described as the change of preexisting life-forms to modern-day organisms. What actually changes, in every case of evolution, is the
Genetic makeup of the species
The storage form of carbohydrates is __________ in animals and in __________ in plants.
Glycogen; starch
Typically, nitrogen atoms are composed of electrons, protons, and neutrons. An isotope of nitrogen could
Have more neutrons than the usual nitrogen atom.
Water's surface tension and heat storage capacity are accounted for by its
Hydrogen bonds
A scientific explanation that is tentative and requires more investigation is called a(n)
Hypothesis
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
We use the scientific method every day. Imagine that your car doesn't start one morning before school. Which of these is a reasonable hypothesis regarding the problem?
I'm out of gas.
Which of the following statements about water is FALSE?
Ice is denser than liquid water.
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 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.
What is meant by the statement that water has a high specific heat?
It can absorb a lot of energy without changing temperature.
A basic difference between a prokaryotic cell and a eukaryotic cell is that the prokaryotic cell
Lacks a nucleus
Lard is a solid fat at room temperature. What does this tell you about the triglycerides in lard?
Lard is composed of saturated fats.
Which level in the hierarchy shown is a community?
Level C.
Which of the following statements about lysosomes is FALSE?
Lysosomes synthesize proteins from the recycled amino acids.
Which of the following is a characteristic of living organisms?
Maintenance of precise internal conditions
Which of the following statements about animal cell lipids is FALSE?
Many lipids function as enzymes.
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
A solution with a pH of 7 is
Neutral
Identify the molecule shown below:
Nucleotide
The atomic number of an atom is defined as the
Number of protons in the atomic nucleus
A hydrogen atom has one electron. How many covalent bonds can hydrogen form?
One
Which statement about the properties of life is FALSE?
Organisms have an unchanging, constant internal environment.
Free radicals contain unpaired electrons in their outermost energy shell, so they react readily with other atoms or molecules to reach a more stable state. Which of the following could potentially be a free radical?
Oxygen (Atomic Number 8)
If you examined the human body, which of the following combinations of elements would be most common?
Oxygen, Nitrogen, Hydrogen, and Carbon
Identify the molecule shown below:
Peptide
Which location in the cell is unlikely to contain ribosomes or ribosomal subunits?
Plasma membrane
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
A molecule with the formula C55H110O55 is probably a(n)
Polysaccharide
Myosin is a contractile protein found in muscles that is composed of three pairs of subunits, two heavy chains, and two pairs of two different types of light chains, for a total of six subunits. Myosin contains what level(s) of protein structure?
Primary, secondary, tertiary, and quaternary.
Which of the following particles are found in the nucleus of an atom?
Protons and neutrons
Identify the two molecules shown below:
Steroid, amino acid
Your friend does a belly flop into the pool. The stinging pain he feels is most likely due to the
Surface tension of the water (caused by the large number of hydrogen bonds that form between water molecules).
Humans born without sweat glands usually do not survive. Why not?
Sweating is an important mechanism for maintaining the correct body temperature.
Which of the following is an example of hydrogen bonding?
The bond between O of one water molecule and H of a second water molecule.
Amino acids can be distinguished from one another by
The chemical properties of their R groups.
Which of the following statements about radioactive isotopes is TRUE?
The energy emitted by radioactive isotopes can cause molecular damage in cells.
Phosphorus has an atomic number of 15, so what is the distribution of its electrons?
The first energy level has 2, the second has 8, and the third has 5.
Which of the following characteristics of a protein will remain intact if the protein is denatured?
The number of amino acids in the protein
Carbon-14 is often used for carbon dating, where scientists measure the rate of carbon-14 decay to determine the age of items. Carbon-14 contains six protons and eight neutrons. During the process of carbon-14 decay, one of its eight neutrons becomes a proton and an electron is emitted. Which of the following is the best explanation of what has occurred?
The resulting atom is now a different element because the number of protons has changed.
Proteins differ from one another because
The sequence of amino acids in the polypeptide chain differs from protein to protein
How do buffers work?
They accept or release H+.
Which of the following is FALSE about scientific theories?
They are firmly established and cannot be refuted.
Which of the following statements about enzymes is FALSE?
They are monomers used to build proteins.
The stroma is the
Thick fluid enclosed by the inner chloroplast membrane
What is the general function of enzymes within a cell?
To speed up chemical reactions
Which of the following statements regarding triglyceride molecules is FALSE?
Triglycerides are hydrophilic.
A single covalent chemical bond represents the sharing of how many electrons?
Two
A disaccharide forms when
Two monosaccharides join by dehydration reactions
Identify the molecule shown below:
Unsaturated triglyceride
A cell is exposed to a substance that prevents it from dividing. The cell becomes larger and larger. This situation
Will eventually be problematic, since the cell's ability to absorb nutrients through its outer membrane will not increase as quickly as its cytoplasmic needs.
The figure below shows five water molecules. The hydrogen bonds shown in this figure are each between
an oxygen and a hydrogen atom of different water molecules.