BIO 100 Test 2
How old are the oldest known fossils? A. 3-4 billion years old B. 30-40 million years old C. 400-500 million years old D. 1-2 billion years old E. 800-900 million years old
A. 3-4 billion years old
What does the cell theory state? A. All living things are made of cells and those cells come from existing cells. B. All cells come from existing cells. C. All cells contain organelles. D. All living cells come from existing cells and those cells contain organelles. E. All living things are made of cells.
A. All living things are made of cells and those cells come from existing cells.
If the concentration of solvents in the blood is too high, A. All of the answers are correct. B. the hypothalamus will release antidiuretic hormone. C. the kidneys will excrete less water. D. your sense of thirst will increase. E. you need to add water to your blood.
A. All of the answers are correct.
The first diverse animal world appeared during the A. Cambrian explosion. B. Silurian explosion. C. Carboniferous explosion. D. Devonian explosion. E. Ordovician explosion.
A. Cambrian explosion.
How are DNA and proteins related? A. DNA stores the information needed to synthesize proteins. B. DNA acts as an enzyme to build and modify most proteins. C. DNA is the template that proteins are translated from. D. DNA provides the raw materials for building proteins.
A. DNA stores the information needed to synthesize proteins.
What makes ice less dense than liquid water? A. Hydrogen bonds between water molecules expand when solid. B. Nuclear forces form expansive crystals as freezing occurs. C. Hydrogen donates electrons to oxygen as freezing occurs. D. Covalent bonds within water molecules expand when solid. E. Ionic bonds between water molecules expand when solid.
A. Hydrogen bonds between water molecules expand when solid
What makes ice less dense than liquid water? A. Hydrogen bonds between water molecules expand when solid. B. Covalent bonds within water molecules expand when solid. C. Hydrogen donates electrons to oxygen as freezing occurs. D. Nuclear forces form expansive crystals as freezing occurs. E. Ionic bonds between water molecules expand when solid.
A. Hydrogen bonds between water molecules expand when solid.
What is DNA? A. a molecule common to all life forms B. a molecule made of a single strand of nucleotides C. a molecule found only in blood D. a molecule found only in mammals E. a molecule that is passed down to children from the father but not the mother
A. a molecule common to all life forms
DNA is found in A. all cells. B. bacterial cells. C. animal and plant cells. D. plant cells. E. animal cells.
A. all cells.
Ribosomes are found in A. all cells. B. plant cells. C. animal cells. D. animal and plant cells. E. bacterial cells.
A. all cells.
Which of the following is/are not associated with human cells? A. cell wall B. All of the answers are associated with human cells. C. cell membrane D. ribosomes E. DNA
A. cell wall
According to the cell theory, all living organisms are composed of A. cells. B. macromolecules. C. phospholipids. D. DNA. E. proteins.
A. cells.
In order to maintain ideal internal conditions, the human body works to maintain _____. A. homeostasis B. regular movement C. insulation D. heat output E. movement
A. homeostasis
What chemical interactions determine how a protein folds? Select the THREE answers that are correct. A. interactions among core structures of amino acids B. interactions among side chains of nucleotides C. interactions between amino acid side chains and water D. interactions between amino acids and nucleotides E. interactions among side chains of amino acids
A. interactions among core structures of amino acids C. interactions between amino acid side chains and water E. interactions among side chains of amino acids
The defining organelle of a eukaryotic cell is the A. nucleus. B. cytoskeleton. C. mitochondrion. D. endoplasmic reticulum. E. Golgi apparatus.
A. nucleus.
The concentration of dissolved solutes in blood is called A. osmolarity. B. thymolarity. C. tonicity. D. hemotonicity. E. osmoregulation.
A. osmolarity.
In a water molecule, hydrogen atoms are bonded to oxygen by _________ bonds, whereas neighboring water molecules are held together by __________ bonds. A. polar covalent; hydrogen B. hydrogen; polar covalent C. polar covalent; ionic D. ionic; polar covalent E. ionic; hydrogen
A. polar covalent; hydrogen
Most tasks in a cell are carried out by A. proteins. B. DNA. C. carbohydrates. D. lipids. E. membranes.
A. proteins.
Transpiration is an effective mechanism for moving water to the leaves in 300-foot-tall trees because of _______. A. the cohesive strength of water that holds water molecules together B. the cellulose and lignin in the walls of xylem cells C. the force of gravity D. the ability of plants to open and close their stomata E. the ability of the central vacuole to release water
A. the cohesive strength of water that holds water molecules together
Which of the following are NOT composed of cells? A. viruses B. bacteria C. humans D. fungi E. plants
A. viruses
Which hormone regulates water conservation by the kidneys? A. insulin B. ADH C. glucagon D. ADH and insulin work together
B. ADH
Which statement is FALSE? A. A protein's function can be altered by just one amino acid change. B. All proteins fold into the same basic three-dimensional shape. C. All proteins begin with the amino acid methionine. D. Some proteins contain more than one amino acid chain. E. The side chains of amino acids are responsible for protein folding.
B. All proteins fold into the same basic three-dimensional shape.
How do properties of amino acids affect the function of proteins? A. Amino acid side chains link individual amino acids to form linear protein molecules, allowing amine and carboxyl groups to determine protein shape and function. B. Amino acids vary in their chemical side chains, and interactions among side chains affect the protein folding that determines protein shape and function. C. Amino acids vary in how much adenine, cytosine, thymine, and guanine are present, and these differences affect the protein folding that determines protein function. D. Amino acids vary in the structure of their amine and carboxyl groups, and interactions among these functional groups affect protein folding and function. E. Amino acid side chains have active and inactive forms, and the pattern of active and inactive side chains determines how the protein folds and functions.
B. Amino acids vary in their chemical side chains, and interactions among side chains affect the protein folding that determines protein shape and function.
How does the DNA of prokaryotic cells differ from the DNA of eukaryotic cells? A. Prokaryotic DNA has a linear structure, whereas eukaryotic DNA has a circular, closed-loop structure. B. Prokaryotic DNA is contained in the cytoplasm, whereas eukaryotic DNA is contained in the nucleus. C. Prokaryotic DNA is protected by a cell membrane, whereas eukaryotic DNA is protected by a cell wall. D. Prokaryotic DNA is composed of four nucleotides, whereas eukaryotic DNA is composed of five nucleotides. E. Prokaryotic DNA is bound by an organelle, whereas eukaryotic DNA is free floating in the cytoplasm.
B. Prokaryotic DNA is contained in the cytoplasm, whereas eukaryotic DNA is contained in the nucleus.
Which statements describe the structure of the cell membrane? Select the TWO answers that are correct. A. The cell membrane is composed of a single layer of phospholipids, each of which contains a hydrophilic head and a hydrophobic tail. B. The hydrophilic head interacts with the external environment or the cytoplasm, and the hydrophobic tail interacts with other phospholipid tails within the cell membrane. C. The hydrophilic head interacts with proteins embedded in the membrane, and the hydrophobic tail interacts with the external environment or the cytoplasm. D. The cell membrane is composed of a bilayer of phospholipids, each of which contains a hydrophilic head and a hydrophobic tail. E. The cell membrane is composed of a bilayer of phosphoproteins, each of which contains a hydrophilic head and a hydrophobic tail.
B. The hydrophilic head interacts with the external environment or the cytoplasm, and the hydrophobic tail interacts with other phospholipid tails within the cell membrane. D. The cell membrane is composed of a bilayer of phospholipids, each of which contains a hydrophilic head and a hydrophobic tail.
A mutation in the gene for insulin results in a protein with a drastically distorted three-dimensional shape. What is the most likely outcome? A. There will be no effect; the shape is rarely important. B. The insulin protein will not function properly. C. Other proteins will be mutated to replace it. D. The effect will be minor, and the protein will mostly function. E. None of the above.
B. The insulin protein will not function properly.
What happens to the central vacuole of plant cells in the absence of water? A. The vacuole swells as water flows out. B. The vacuole shrinks as water flows out. C. The vacuole remains constant in size. D. The vacuole expands as water flows in. E. The vacuole deflates as water flows in.
B. The vacuole shrinks as water flows out.
A protein is made up of a chain of _____. A. nucleotides B. amino acids C. simple sugars D. fatty acids E. lipids
B. amino acids
What determines a protein's function? A. the three-dimensional shape of the folded protein B. both the sequence of amino acids and the three-dimensional shape of the folded protein C. All of the answers are correct. D. the sequence of amino acids E. the location of its gene on the chromosome
B. both the sequence of amino acids and the three-dimensional shape of the folded protein
Which of these cellular components is(are) associated with all cells? A. cell membrane B. cell membrane, ribosomes, and DNA C. ribosomes D. cell membrane and ribosomes E. DNA
B. cell membrane, ribosomes, and DNA
DNA is a type of molecule called a _________. Its smaller parts are called __________. A. protein; amino acids B. deoxyribonucleic acid; nucleotides C. nucleotide; deoxyribonucleic acids D. deoxyribonucleic acid; amino acids E. protein; nucleotides
B. deoxyribonucleic acid; nucleotides
The first multicellular eukaryotic organisms to use the oxygen on Earth were _____. A. jelly fish B. green algae C. humans D. amphibians E. Tiktaaliks
B. green algae
Olive oil is _______________ because _____________________. A. both hydrophilic and hydrophobic; it interacts with water and oil B. hydrophobic; it does not interact with water C. hydrophobic; it interacts with water D. hydrophilic; it does not interact with water E. hydrophilic; it interacts with water
B. hydrophobic; it does not interact with water
The organ that regulates the body's water balance is the A. hypothalamus. B. kidney. C. heart. D. liver. E. bladder.
B. kidney.
This gas began to accumulate between 3 and 2.5 billion years ago. A. ammonia B. oxygen C. carbon dioxide D. methane E. hydrogen
B. oxygen
In plants, _____ transports ______ from ______. A. xylem; sugars; leaves to roots B. phloem; sugars; leaves to roots and roots to leaves C. xylem; water; leaves to roots and roots to leaves D. xylem; water; leaves to roots E. phloem; sugars; leaves to roots
B. phloem; sugars; leaves to roots and roots to leaves
In your body, what kind of molecule acts as an enzyme, helps to transport other molecules, and gives structural support in many cells? A. carbohydrate B. protein C. sugar D. lipid E. nucleic acid
B. protein
What is the function of DNA? A. serves as a barrier to the environment in the cell membrane B. stores chemically coded, heritable information in an organism C. transfers genetic information from the nucleus to the cytoplasm D. lowers the activation energy of important chemical reactions E. activates enzymes from inactive states under specific conditions
B. stores chemically coded, heritable information in an organism
Select the parts that make up the backbone of the DNA molecule. Select the TWO answers that are correct. A. nitrogenous base B. sugar C. glycine D. nucleoside E. phosphate
B. sugar E. phosphate
The evidence that scientists currently have suggests that life on Earth _____. A. first evolved in the water around 3,500 million years ago B. first evolved around 3,500 million years ago C. all of these D. began in the water E. began as single-celled organisms
C. all of these
Which of the following is NOT a property of water? A. Water is liquid at 4°C. B. Due to unequal sharing of electrons, water molecules are polar. C. All biological molecules will dissolve in water. D. Water molecules adhere to charged surfaces. E. Water molecules are cohesive to other water molecules.
C. All biological molecules will dissolve in water.
If the concentration of solvents in the blood is too high, A. your sense of thirst will increase. B. the hypothalamus will release antidiuretic hormone. C. All of the answers are correct. D. you need to add water to your blood. E. the kidneys will excrete less water.
C. All of the answers are correct.
What internal signals are associated with dehydration? A. high osmolarity B. low blood pressure C. All of these options are internal signals associated with dehydration. D. low blood volume
C. All of these options are internal signals associated with dehydration.
Which molecules have not been synthesized from experiments similar to the ones performed by Miller and Urey? A. lipids B. amino acids C. DNA D. sugars E. ATP
C. DNA
According to the cell theory, which of the following is NOT considered a living organism? A. diatoms B. protist C. Influenza virus D. amoeba E. yeast
C. Influenza virus
Because of the polar nature of water, it is a universal A. solute. B. suspension. C. solvent. D. solution. E. salt.
C. Solvent
The evidence that scientists currently have suggests that life on Earth _____. A. began in the water B. first evolved around 3,500 million years ago C. all of these D. first evolved in the water around 3,500 million years ago E. began as single-celled organisms
C. all of these
The "endosymbiotic hypothesis" is a concept that explains _____. A. why ribosomes are only found in the eukaryotic cytoplasm, never inside an organelle B. why mitochondria and chloroplasts are so unlike each other C. how eukaryotic cells might have evolved mitochondria and chloroplasts within their cells D. why chromosomes are only found inside the nucleus of a eukaryotic cell E. how plant cells produce usable cellular energy from sunlight
C. how eukaryotic cells might have evolved mitochondria and chloroplasts within their cells
The following are effects of dehydration, EXCEPT A. altered electrolyte concentrations in blood. B. altered muscle contractions. C. increased blood pressure. D. delirium and confusion. E. concentrated urine.
C. increased blood pressure.
The kidneys respond to a decrease in osmolarity by _____. A. increasing or decreasing water excreted in the urine B. decreasing water excreted in the urine C. increasing water excreted in the urine D. signaling the hypothalamus to increase ADH secretion E. producing antidiuretic hormone (ADH)
C. increasing water excreted in the urine
Woody plants such as giant redwoods contain greater amounts of substances that make them tougher and more rigid than other plants, and other woody plants, such as cellulose and _____. A. turgor B. water C. lignin D. phloem E. vacuoles
C. lignin
In order to crisp up some wilted celery, what should you soak it in? A. Any of these solutions would be equally effective. B. a solution with the same solute concentration as the celery C. pure water D. a solution with a higher solute concentration than the celery E. you should let it air dry for a few minutes
C. pure water
In most plants, water and minerals are absorbed by _______. A. the stems and roots B. the stems C. the roots D. the leaves, stems, and roots E. the leaves
C. the roots
What is the final product of gene expression? A.an RNA molecule B.a ribosome C.a protein D. a DNA molecule E.an amino acid
C.a protein
Put the following in order of their evolution. A. algae→vertebrates→ amphibians→reptiles→mammals→invertebrates B.invertebrates→algae→vertebrates→reptiles→amphibians→mammals C.algae→invertebrates→vertebrates→amphibians→reptiles→mammals D.invertebrates→algae→amphibians→birds→reptiles→mammals E.algae→invertebrates→vertebrates→reptiles→amphibians→mammals
C.algae→invertebrates→vertebrates→amphibians→reptiles→mammals
The _____ of water molecules explains how some insects can walk on water. A. adhesion B. solubility C. movement D. aversion E. cohesion
Cohesion
How many different amino acids are responsible for making up the thousands of different proteins found in a cell? A. 4 B. thousands C. 3 D. 20 E. 15
D. 20
Where is the information for building proteins encoded? A. sidechains B. beta sheets C. spidroins D. DNA E. amino acids
D. DNA
_____amino acids tend to be found folded inside a protein, whereas _____ amino acids interact with water on the outside of the protein. A. All; protein B. Protein; carbohydrate C. All; only limited D. Hydrophobic; hydrophilic E. Hydrophilic; hydrophobic
D. Hydrophobic; hydrophilic
How does water dissolve table salt? A. Water is a polar molecule that takes electrons from sodium chloride. B. Water is a polar molecule that disrupts hydrogen bonds between sodium and chloride. C. Water is a nonpolar molecule that breaks the ionic bonds between sodium and chloride. D. Water is a polar molecule that disrupts ionic bonds between sodium and chloride. E. Water is a nonpolar molecule that dissolves covalent bonds between sodium and chloride.
D. Water is a polar molecule that disrupts ionic bonds between sodium and chloride.
Which of the following statements represents a true distinction between xylem and phloem? A. All of these statements represent distinctions between xylem and phloem. B. Xylem transports sugars in either direction; phloem transports water from roots to shoots. C. Xylem transports materials from shoots to roots; phloem transports materials in either direction. D. Xylem provides water and nutrient transport; phloem provides sugar transport. E. Xylem provides support only; phloem provides transport.
D. Xylem provides water and nutrient transport; phloem provides sugar transport.
Cell membranes are found in A. animal and plant cells. B. animal cells. C. plant cells. D. all cells. E. bacterial cells.
D. all cells.
Cell membranes are found in A.animal and plant cells. B. plant cells. C. bacterial cells. D. all cells. E. animal cells.
D. all cells.
Mitochondria are found in A. plant cells. B. animal cells. C. all cells. D. animal and plant cells. E. bacterial cells.
D. animal and plant cells.
Which of the following is/are not associated with human cells? A. DNA B. cell membrane C. All of the answers are associated with human cells. D. cell wall E. ribosomes
D. cell wall
The surface tension of water is an example of A. capillary action. B. covalent bonding. C. adhesion. D. cohesion. E. strong hydrogen bonds.
D. cohesion.
Dehydration is associated with _______ osmolarity and _______ blood pressure. A. low; high B. high; high C. no change in; no change in D. high; low E. low; low
D. high; low
The "stickiness" of water results from the ______________ bonding of water molecules. A. covalent B. hydrophobic C. acidic D. hydrogen E. ionic
D. hydrogen
Which of the following is not found in prokaryotic cells? A. cell membrane B. cell membrane and ribosomes C. cytoplasm D. mitochondria E. ribosomes
D. mitochondria
The first organisms on land were A. insects. B. fish. C. reptiles. D. plants. E. amphibians.
D. plants.
Proteins do all of the following tasks EXCEPT A. carry out chemical reactions. B. help blood to clot. C. regulate processes within the body. D. store information. E. give structure to cells, such as hair, skin, and muscle.
D. store information.
When life first began, A. the planet had very little oxygen in the atmosphere and was much cooler. B. the planet had a lot of methane in the atmosphere and was much cooler. C. the planet had a lot of oxygen in the atmosphere and was much cooler. D. the planet had a lot of methane in the atmosphere and was much warmer. E. the planet had a lot of oxygen in the atmosphere and was much warmer.
D. the planet had a lot of methane in the atmosphere and was much warmer.
Earth is estimated to be around A. 4,600,000,000,000 years old. B. 4,600,000 years old. C. 4,000-6,000 years old. D. 6,000-8,000 years old. E. 4,600,000,000 years old.
E. 4,600,000,000 years old.
What is the function of the cuticle? A. It is toxic to many herbivorous insects. B. It provides rigidity to the cell wall. C. It enables neighboring cells to stick together. D. It is sticky and helps pollen adhere to a plant during pollination. E. It prevents water loss.
E. It prevents water loss.
How does the molecular structure of a water molecule affect its polarity? A. The oxygen takes an electron from each hydrogen, yielding a negatively charged oxygen and two positively charged hydrogens that can form hydrogen bonds. B. The oxygen and hydrogen rapidly exchange electrons in their outermost energy shells, producing structures that can form hydrogen bonds. C. The oxygen has a partial positive charge and the hydrogens have a partial negative charge, yielding a weakly polar water molecule that can form hydrogen bonds. D. The oxygen donates an electron to each hydrogen, yielding a positively charged oxygen and two negatively charged hydrogens that can form hydrogen bonds. E. The oxygen has a partial negative charge and the hydrogens have a partial positive charge, yielding a weakly polar water molecule that can form hydrogen bonds.
E. The oxygen has a partial negative charge and the hydrogens have a partial positive charge, yielding a weakly polar water molecule that can form hydrogen bonds.
People who are severely dehydrated produce _________________ of urine that is ___________________. A. a low volume; dilute and light in color B. a normal volume; a normal color (neither very light nor very dark) C. a high volume; dilute and light in color D. a high volume; highly concentrated and dark in color E. a low volume; highly concentrated and dark in color
E. a low volume; highly concentrated and dark in color
What is a protein? A. a macromolecule that is made from various nucleotides B. a molecule that comes in many shapes but is always the same size C. a molecule that comes in many sizes but is always the same shape D. a molecule that plays only a minor role in cellular function E. a macromolecule that is made from various amino acids
E. a macromolecule that is made from various amino acids
Which statement describes a hydrogen bond between two water molecules? A. a weak bond in which the oxygen atom of one molecule donates an electron to the hydrogen atom of another water molecule B. a weak bond in which the oxygen atom of one molecule stably shares electrons with the hydrogen atom of another water molecule C. a weak bond in which the oxygen atom of one molecule takes an electron away from the hydrogen atom of another water molecule D. a weak bond between the slightly positive oxygen atom of one water molecule and the slightly negative hydrogen atoms of another water molecule E. a weak bond between the slightly negative oxygen atom of one water molecule and the slightly positive hydrogen atoms of another water molecule
E. a weak bond between the slightly negative oxygen atom of one water molecule and the slightly positive hydrogen atoms of another water molecule
The attraction water molecules have for other water molecules is called _____________, whereas the attraction water molecules have for non-water molecules is called _____________. A. adhesion; cohesion B. ionic bonding; cohesion C. adhesion; ionic bonding D. cohesion; ionic bonding E. cohesion; adhesion
E. cohesion; adhesion
Miller and Urey demonstrated the formation of organic molecules from simulating a primitive Earth atmosphere containing water vapor and the gases A. oxygen, hydrogen, methane, and ammonia. B. oxygen, methane, and ammonia. C. carbon dioxide, hydrogen, methane, and ammonia. D. carbon dioxide, methane, and ammonia. E. hydrogen, methane, and ammonia.
E. hydrogen, methane, and ammonia.
All of the following are true of water EXCEPT A. it is the basis for all life as we know it. B. it is less dense as a solid than as a liquid. C. neighboring molecules are held together by hydrogen bonds. D. it can dissolve molecules with electrical charges. E. it is a polarized molecule, where the oxygen is slightly positive and the hydrogens are slightly negative.
E. it is a polarized molecule, where the oxygen is slightly positive and the hydrogens are slightly negative.
Homeostasis is best defined as A. maintaining constant body temperature. B. maintaining constant blood-glucose levels. C. maintaining a constant internal environment. D. maintaining constant blood pressure. E. maintaining a constant internal environment in spite of a changing external environment.
E. maintaining a constant internal environment in spite of a changing external environment.
Hydrophobic means A. something with a negative charge. B. not quite alive, like a virus. C. water loving. D. a solute. E. something that will not dissolve in water.
E. something that will not dissolve in water.
Water vapor leaves plants through openings called _______. A. stamens B. root hairs C. cuticles D. pistil E. stomata
E. stomata
What is the function of DNA? A. lowers the activation energy of important chemical reactions B. activates enzymes from inactive states under specific conditions C. serves as a barrier to the environment in the cell membrane D. transfers genetic information from the nucleus to the cytoplasm E. stores chemically coded, heritable information in an organism
E. stores chemically coded, heritable information in an organism
The Miller-Urey experiment was important because it showed _____. A. when life first began on Earth B. exactly how life began on Earth C. the kinds of rocks that would contain fossils D. all of these E. that is was possible to form organic molecules from inorganic molecules
E. that is was possible to form organic molecules from inorganic molecules
Transpiration is an effective mechanism for moving water to the leaves in 300-foot-tall trees because of _______. A. the ability of plants to open and close their stomata B. the cellulose and lignin in the walls of xylem cells C. the force of gravity D. the ability of the central vacuole to release water E. the cohesive strength of water that holds water molecules together
E. the cohesive strength of water that holds water molecules together
True or False: The sequence of its amino acids determines the shape of a protein.
True