Study Guide for Chapter 1-3
All living things require an outside source of materials and energy. All of the chemical reactions that occur within a cell to provide these materials and energy are called
metabolism
When atoms have more than one electron shell, the valence shell is full when it contains ___ electrons.
8
_______ is a strong base because it almost fully dissociates into hydroxide ions and ______ ions in water.
NaOH, sodium
Which kingdom includes both unicellular and multicellular organisms? a) Bacteria b) Protista c) Fungi d) Eukarya e) Plantae
b
Which of the following correctly lists the classification categories from least to most inclusive? a) kingdom, phylum, domain, class, order family, genus, species b) species, genus, family, order, class, phylum, kingdom, domain c) phylum, species, genus, kingdom, domain, order, class, family d) domain, kingdom, class, order, family, phylum, genus, species e) species, genus, family, class, order, domain, phylum, kingdom
b
Which of the following pairs of words is matched correctly? a) neuron - tissue b) brain - organ c) gene - atom d) heart - organ system e) osteocyte - organelle
b
Which of the following processes transforms solar energy into chemical energy? a) respiration b) photosynthesis c) homeostasis d) metabolism e) reproduction
b
Because of the high number of hydrogen bonds, water exhibits ______, meaning the molecules cling together. Under ordinary conditions of temperature and pressure, water exists as a _______.
cohesion, liquid
The process of ________ leads to organisms that are ________ that environment. a) adaption; evolved for b) homeostasis; suited to c) adaptation; only found in d) natural selection; adapted to e) natural selection; perfect for
d
The scientific method a) ends after the experiment. b) begins with the hypothesis. c) ends with the predictions. d) begins with observations. e) does not require a hypothesis.
d
Sunlight striking plants and the heat released by producers, consumers, and decomposers are all components of _____ within an ecosystem
energy flow
It is estimated that there are as many as 15 million species in the world, all as a result of 3.5 billion years of
evolution
The process in which populations accumulate adaptations over time to become more suited to their environments is called ______. It is considered the unifying concept of ______, which is the study of life.
evolution, biology
Human activity has increased the rate of _______ by a factor of 100 to even 1000!
extinction
These favorable traits cause higher reproductive success and increase the______ of these traits from one ______ to the next.
frequency, generation
Fish produce many offspring that inherit the ______for body color
genes
Within a population of fish, ______ exists in the form of body color. Some fish are orange and some fish are red.
genetic variations
Human activity is increasing the levels of atmospheric carbon dioxide, resulting in a rise in temperature called ________. This process is causing disruptions in the normal cycles of the Earth's ______
global warming, climate
In high amounts, radioactive isotopes can be _____ to humans.
harmful
The more hydroxide ions released or the more hydrogen ions taken up by bases, the _______ the pH value of the solution
higher
However, for these processes to continue, living things must maintain ______, or the maintenance of internal conditions within certain boundaries.
homeostasis
Water can also be used as a ______ for many polar and ionic substances. Molecules that are attracted to water are said to be _______.
solvent, hydrophilic
Isotopes that are radioactive can also be used to _______ medical equipment and even food.
sterilize
The electrons that are in the outermost electron shell, also known as the ________, have ______ energy than those in the inner electron shells.
valence shell, more
An atom of helium has one electron shell and it is full when it contains ___ electrons.
2
Organic nutrients that move from one population to another in a food chain is an example of ________ within an ecosystem
Chemical cycling
The sun is the ultimate source of energy for nearly all of life. Plants and certain other organisms convert solar energy into _______energy through the process of______
Chemical, Photosynthesis
_____ is a strong acid because it almost fully dissociates into hydrogen ions and ______ ions in water.
HCI, Chloride
In general, evolutionary processes lead to organisms that a) function well in a given environment. b) can only survive in that one environment. c) become extinct. d) have a single adaptive trait. e) are perfect.
a
Is the following statement true or false? The only single-celled organisms are prokaryotes, such as archaeans and bacteria. a) false, because some eukaryotes, including protista, are single-celled b) true, because prokaryotes are the simplest cell form c) true, because all eukaryotes are multicellular d) false, because some prokaryotes are multicellular e) false, because all single-celled organisms are prokaryotes
a
Many insects cannot see the color red, and as a result many insect-pollinated flowers are colors other than red (e.g., purple and yellow). Flower color would be considered a(n) a) adaptation. b) example of energy flow. c) example of nutrient cycling. d) method for maintaining homeostasis. e) way to maintain metabolism.
a
Substances that release hydrogen ions when dissociated in water are called _______
acids
Penguins have extra layers of feathers, a layer of blubber, and feet and tails that serve as rudders. Collectively, these ______ make them suitable for life in a cold, aquatic exististence.
adaptations
Organisms exhibit ________ by interacting with and responding to their environment. For example, lizards lounge on rocks in sunny locations to warm their bodies and seek shade to cool their bodies.
behaviors
Defined as variation of life on Earth, _______ is the number of different ________.
biodiversity, species
Energy flow and chemical cycling in an ecosystem determine where different ecosystems are found in the
biosphere
The phrase "common _____ with modification" sums up the process of evolution, which shows that one species can be a common ______to several species, each adapted to a particular set of environmental conditions.
descents, ancestors
Emerging _______ may result from new and/or increased exposure to animal or insect populations and can be rapidly transported to vast areas because of ________
diseases, globalization
Magnesium wants to have 8 electrons, so it ______ 2 electrons to another atom, so its valence shell is full and a ______ is created between the two atoms.
donates, bond
In water, oxygen shares a bond with two hydrogen atoms. Oxygen is more __________ than hydrogen, making the bond ______ with the oxygen being the negative end and the two hydrogens being the positive end.
electronegative, polar
The process of ______ explains how a population changes in response to its environment.
natural selection
In this manner, ________is determining the color of the fish population. This may lead to a new species of fish and contribute to the larger process of ________.
natural selection, evolution
Isotopes are atoms of the same element that contain different numbers of ______
neutrons
The energy levels in which electrons orbit around the ______ are also called _________
nucleus, electron shells
Because fish that are ______ are more likely to blend in and resist predation, they are more likely to survive to reproduce.
orange
The fish population lives on an orange reef bed. Because of this, fish that are ______ are able to blend in and resist predation.
orange
As the human _______ grows and demands more resources, biodiversity is threatened by humans modifying _______ for their own purposes.
population, ecosystems
Plants that provide energy in the form of nutrient molecules are known as
producers
Because of this, isotopes have the same number of _____, but a different ________
protons, mass number
Isotopes that are _______ are used in medicine as tracers to detect and destroy dangerous cells.
radioactive
Simon is an avid gardener who spends a lot of time caring for the plants in his garden. To minimize damage from pests from his garden, Simon uses a pesticide spray. After a few years of using the same pesticide spray, he notices that it has become less effective. This is most likely due to a) evolution by natural selection. b) the plants maintaining homeostasis. c) the plants in the garden evolving. d) using the spray incorrectly. e) something else in the environment.
a
The smallest, most basic unit of life is a(n) a) cell. b) organism. c) organ. d) species. e) tissue.
a
The various species of honeycreepers have an assortment of different beak shapes, but all honeycreeper species have a similar size and body shape. This is an example of a) descent with modification. b) taxonomic differentiation. c) modification of adaptations. d) fixed traits. e) ascent with new traits.
a
Which of the following is the most inclusive level of organization? a) ecosystem b) class c) species d) cells e)population
a
Heartburn occurs when stomach acid escapes the stomach and burns the tissues of the esophagus. Baking soda is sometimes used as an antacid. How does baking soda help relieve symptoms of heartburn? a) The baking soda is serving as a buffer to take up excess H+ ions from stomach acid. b) The baking soda increases the acidity of the stomach. c) The baking soda relaxes the stomach muscles. d) The baking soda releases salt which draws more water into the esophagus thereby diluting the acid. e) The baking soda is able to coat the lining of the esophagus thereby protecting it from the acid.
a Explanation Baking soda acts as a buffer and takes up the excess hydrogen ions (H+) in the esophagus and stomach. This helps to relieve the symptoms of heartburn.
After drinking a great deal of coffee (pH 5), a human's blood buffering system would need to ________ as the coffee was digested to lower the level of acid present in the blood stream. a) take up H+ b) release OH- and take up H+ c) take up OH- d) release H+ e) release OH-
a Explanation Human physiologic pH should be 7.4. Coffee acidifies the blood. To maintain homeostasis, buffers would take up the excess H+ returning the blood pH to normal.
The figure below is depicting the interaction of water molecules with one another. The weak attractions between water molecules are known as a) hydrogen bonds. b) Ionic bonds. c) covalent bonds. d) postive and negative ions. e) no chemical bonding.
a Explanation The positive hydrogen forms a hydrogen bond with the negative oxygen from a nearby molecule. No electron transfer or sharing is occurring in this type of bond. It is a weak attraction between polar molecules.
As the environment changes over time, some individuals may possess certain ______ that make them better suited to live longer and produce more ______.
adaptions, offspring
Water also exhibits ______, which is the ability to cling to other polar surfaces, because of its polarity.
adhesion
Which of the following statements is correctly matched to the step of the scientific method? a) Biologists suggested that 2-3 cups of coffee per day can decrease death rates among women. (Hypothesis) b) All of the above statements are correctly matched. c) A researcher reported that red-foot tortoises preferred red-colored fruits and vegetables to those that were green or white. (Conclusion) d) Bethany watched butterflies feeding in a large field of wild flowers. She noticed that more butterflies approached the yellow and purple flowers than the red flowers. (Observation) e) Leslie set up mist nets to catch bats flying over a small stream. Each bat that was caught was weighed and sexed. (Experimental design)
b
Which of the following statements about atoms is correct? a) An element may be composed of several types of atoms. b) The number and arrangement of electrons in an atom governs its chemical activity. c) The nucleus of an atom contains protons and electrons. d) The neutral charges of an element are carried by the protons. e) The positive charges of an element are carried by the electrons.
b Explanation An atom is comprised of subatomic particles. Protons are positively charged, electrons are negatively charged and neutrons have no charge (they are neutral). The neutrons and protons are located in the atomic nucleus and contribute to the majority of an atom's mass. The electrons, which orbit the nucleus, are negatively charged and govern the element's reactivity.
The four main categories of organic macromolecules are a. proteins, DNA, waxes, and sugars. b. carbohydrates, lipids, proteins, and nucleic acids. c. monosaccharides, disaccharides, trisaccharides, and polysaccharides. d. RNA, DNA, steroids, and fats. e. lipids, starches, DNA, and protein.
b Explanation Biological molecules are grouped into four categories: carbohydrates, lipids, proteins, and nucleic acids.
Which one of the following is the smallest unit of matter that has all the properties of an element? a) molecule b) atom c) electron d) proton e) compound
b Explanation Elements are comprised of one kind of atom. These atoms all have the same atomic number, which means they all have the same number of protons. Molecules have more than one atom present and compounds are composed of two or more different types of elements. Therefore, neither molecules nor compounds are in their simplest form.
A covalent bond involves the sharing of a) at least three electrons. b) pairs of electrons. c) protons. d) neutrons. e) pairs of protons.
b Explanation In order to form covalent bonds each atom must contribute an equal number of electrons. Therefore, electrons are shared in pairs.
An ionic bond forms when a) an atom gives away or takes in an electron. b) a negatively charged ion is attracted to one with a positive charge c) two atoms come close enough to share one or more protons. d) two atoms come close enough to share one or more electrons. e) an atom gives away or takes in a proton.
b Explanation Ions form when an atom gives away or takes in an electron. An ionic bond forms when two oppositely charged ions attract.
Which of the following would be an example of the value of water's heat capacity? a) Small insects can walk on water. b) Living organisms are able to maintain their internal body temperatures because the water in their cells resists changes in temperature. c) Water expands as it freezes causing ice to float on the surface of a lake. d) Water molecules stick together. e) Water is able to travel up a 100-foot tree
b Explanation Water has the ability to absorb heat without greatly changing in temperature. Because the temperature of water rises and falls slowly, organisms are better able to maintain their normal internal temperatures and are also protected from rapid temperature changes.
The type of bond that would form from the transfer of an electron from one atom to another is a(n) ________ bond. a) isotopic b) ionic c) hydrogen d) covalent e) atomic
b Explanation : An ionic bond forms when two atoms are held together by the attraction between opposite charges. An ionic bond occurs when one atom gives up electrons (and becomes positively charged) and another atom gains the electrons (and becomes positively charged).
A pond ecosystem includes small water fleas which feed on submerged aquatic plants. When the water fleas die, they sink to the bottom of the pond where their dead bodies are broken down with the help of bacteria. List in order the producer, decomposer, and consumer in this system a) aquatic plants, water fleas, bacteria b) water fleas, bacteria, aquatic plants c) aquatic plants, bacteria, water fleas d) bacteria, aquatic plants, water fleas e) bacteria, water fleas, aquatic plants
c
As autumn approaches, white-tailed deer begin to accumulate a layer of body fat. This is an example of which characteristic of life? a) maintaining homeostasis b) energy regulation c) response to the environment d) metabolism e) organization
c
Based on the evolutionary tree of the three domains, which of the following statements is true? a) The Eukarya have remained the same throughout evolutionary time. b) All three domains are equally related to one another. c) All three domains have a common ancestor. d) The Eukarya are the common ancestor to the three domains. e) Domain Bacteria and domain Eukarya are more closely related to each other than to domain Archaea.
c
Which answer choice lists the steps of the scientific method in the correct order? a) prediction, conclusion, hypothesis, experiment, observation b) conclusion, hypothesis, observation, experiment, predictions c) observation, hypothesis, prediction, experiment, conclusion d) hypothesis, observation, experiment, conclusion, predictions e) observation, experiment, hypothesis, conclusion, prediction
c
Of the following examples, which best demonstrates the property of water cohesion? a) A large body of fresh water takes a long time to warm up after the winter season. b) Water requires a great deal of heat to reach the point of vaporizing. c) Water can move up a 100-foot pine tree, from the roots to the leaves. d) A rock skipping across the surface of a lake. e) A can of soda bursts when it is placed in the freezer.
c Explanation Cohesion refers to the ability of water molecules to cling to each other due to hydrogen bonding. Within the long narrow vessels of a plant, water molecules cling to each other and form a long chain that stretches from the roots to the leaves. When one water evaporates from the leaves, is immediately replaced with the water molecules below it.
Isotopes of an atom differ in their a) number of electrons. b) atomic number. c) atomic mass. d) number of protons. e) atomic radius.
c Explanation Isotopes are atoms of the same element that differ in the number of neutrons. They have the same number of protons, but they have different mass numbers.
Which of the following is a way in which chemical bonds can be formed? a) gaining electrons b) sharing electrons c) All of the answers describe ways that chemical bonds can be formed. d) losing electrons e) attracting opposite charges
c explanation: Compounds and molecules are formed when atoms form either ionic or covalent bonds. These two result from either the sharing of outer shell electrons or the transfer of the electrons from one atom to another.
Water has a high heat _________, which allows it to absorb heat without greatly changing its temperature, and a high heat of ________, which prevents it from easily becoming a gas and evaporating into the environment.
capacity, vaporization
Which of the following can be categorized as prokaryotic? a) domain Eukarya b) kingdom Plantae c) kingdom Protista d) domain Archaea e) kingdom Animalia
d
Which of the following correctly lists the levels of biological organization from simplest to most complex? a) organs, organ system, organism, cells, tissues b) organ systems, tissues, cells, organism, organs c) tissues, organs, organ systems, organism, cells d) cells, tissues, organs, organ systems, organism
d
Which of the following levels of biological organization is correctly matched with an example? a) flowers and insects in a garden - organism b) a rock garden with various plants and rocks of different sizes - population c) a herd of bison - community d) a desert with little water, high heat, sand, cacti, and some mammals - ecosystem
d
The term "functional" is used in the phrase "functional group" because it describes a group of atoms that a. are organic. b. make the entire molecule hydrophilic. c. make the entire molecule hydrophobic. d. help determine the chemical properties of an organic molecule. e. prevent interaction with other molecules.
d Explanation A functional group is a specific combination of bonded atoms that always has the same chemical properties and therefore always reacts in the same way, regardless of the particular carbon skeleton to which it is attached. The functional groups of an organic molecule help determine its chemical properties.
Which of the following is a property of acids? a) Acids have a pH reading above 7.0. b) Acids taste bitter. c) Acids feel slippery when touched. d) Acids have a sharp or sour taste. e) Acids release OH- when dissolved in a liquid.
d Explanation Acids have a sharp sour taste, a pH below 7.0, and release hydrogen ions in water. Bases have a bitter taste, feel slippery, a pH above 7.0, and release hydroxide ions when dissolved in water.
Chemical bonds involve a) the giving and taking of protons. b) the sharing of electrons. c) the giving and taking of electrons. d)the giving, taking, or sharing of electrons. e) the giving, taking, or sharing of protons.
d Explanation As atoms give, take, or share electrons so that the valence level of the atom is full, they form bonds with the other atom(s) involved in the exchange.
Which of the following would be considered a trace element in living things? a) oxygen b) carbon c) nitrogen d) zinc e) hydrogen
d Explanation Four elements, carbon, hydrogen, nitrogen, and oxygen, make up about 96% of the body weight of most organisms. A number of elements, including minerals such as zinc and chromium, are found at very low, or trace, levels.
The reactivity of an atom depends on the number of a) protons. b) protons and electrons. c) protons plus neutrons. d) valence electrons e) neutrons.
d Explanation The bonds between different atoms arise from the giving, taking, or sharing of the electrons in the outer energy level (valence electrons).
The electron arrangement for argon, which has 18 electrons, is a) 7 in the inner electron shell, 6 in the second electron shell, and 5 in the outer electron shell. b) 5 in the inner electron shell, 6 in the second electron shell, and 7 in the outer electron shell. c) 8 in the inner electron shell, 8 in the second electron shell, and 2 in the outer electron shell. d) 2 in the inner electron shell, 8 in the second electron shell, and 8 in the outer electron shell. e) 6 in the inner electron shell, 6 in the second electron shell, and 6 in the outer electron shell.
d Explanation With 18 electrons, argon has all three electron levels filled. The most that the one closest to the nucleus can hold is 2, the most that the second one can hold is 8, and the final one can also hold 8 at most.
In what ways are radioactive isotopes potentially harmful? a) They are used to trace the path of materials throughout the body. b) They are used to trace molecular changes. c) They are used to determine the age of biological specimens. d) Unmonitored release into the environment can make changes in a cell's DNA e) They are used to destroy abnormal cells.
d explanation: Radioactive isotopes are important in biology and medicine. They can be used to trace molecular changes, destroy abnormal cells, and play a significant role in the ability to determine the age of biological specimens. Their danger comes in their unmonitored release into the environment, where they can make changes in cells, damage DNA, cause cancer, or at their worst be lethal.
All the chemical reactions that occur in a cell are collectively called a) mitosis. b) cellular respiration. c) photosynthesis. d) meiosis. e) metabolism.
e
For metabolic processes to occur within their cells, all living organisms need to maintain homeostasis which means they need a) to constantly evolve as the environment changes around them. b) to rely on the external conditions in the environment to maintain their body temperature. c) to eat other organisms for energy and nutrition. d)minute to minute and day to day fluctuations in body temperature, moisture level and acidity. e) to maintain the correct internal temperature, moisture level, and acidity as well as other factors.
e
The circulatory system of a whale is considered an organ system because it is composed of different a) hearts. b) tissues. c) cells. d) molecules. e) organs.
e
The purpose of a control group in an experiment is a) for comparison to the results of other experiments. b) to prove the hypothesis. c) to prove the prediction. d) to control the dependent variable. e) for comparison to the other test groups.
e
A(n) ________ can be defined as a substance that keeps pH within established limits by taking up excess H+ or OH- in a solution. a) base b) equalizer c) acid d) solute e) buffer
e Explanation A buffer is a chemical that serves to neutralize an acid or a base in solution. Buffers help to resist pH changes because they can take up excess hydrogen ions (H+) or hydroxide ions (OH-).
A water molecule, as shown here, is polar because of a) the transfer of electrons. b) its hydrogen bonds. c) the negative charge of the molecule. d) its ability to freeze. e) unequal sharing of electrons.
e Explanation Atoms differ in their affinity for electrons in a covalent bond (electronegativity). Oxygen is more electronegative than hydrogen. Consequently, the shared electrons spend more time near the oxygen nucleus than the hydrogen nuclei. This gives the oxygen a slight negative charge and the hydrogen atoms slight positive charges. This unequal sharing of electrons makes it a polar molecule.
Which of the following statements about basic solutions is true? a) Basic solutions have high concentrations of H+. b) Basic solutions release both H+ and OH-. c) Basic solutions have a neutral pH. d) Basic solutions have a pH under 7. e) Basic solutions release OH-.
e Explanation Basic solutions either take up hydrogen ions (H+) or release hydroxide ions (OH-) and have a pH higher than 7.
When a sodium atom transfers an electron to a chlorine atom a) the chlorine atom becomes a negatively charged ion. b)the positive and negative ions will attract each other, forming a crystal if no water is present. c) the ions will separate in the presence of water. d) the sodium atom becomes a positively charged ion. e) All of the above statements are correct.
e Explanation Ionic bonds are formed when two atoms are held together by an attraction between ions. Sodium transfers a negatively charged electron over to chlorine. The result is sodium having a positive charge (Na+) and chlorine now having a negative charge (Cl-). These ions have an attraction that creates the ionic bond that holds them together. Ionic compounds are often found as salts, solid substances that usually separate and exist as individual ions in water.
Isotopes of an element differ in their a) proton number. b) type of bonds. c) electron number. d) atomic number. e) neutron number.
e Explanation Isotopes are atoms of the same element that differ in the number of neutrons. They have the same number of protons, but because they have different numbers of neutrons, they have different mass numbers.
In the reaction 6CO2 + 6H2O → C6H12O6 + 6O2 carbon dioxide is one of the a) ions. b) enzymes. c) products. d) elements. e) reactants.
e Explanation The reactants are the molecules that participate in the reaction and are shown on the left side of the reaction arrow. The products are the molecules that are formed by the reaction and are shown on the right.
Which of the following property of water helps an individual who is exercising vigorously maintain a constant body temperature? a) Water is a good solvent. b) Water moleculesare adhesive. c) Water molecules are cohesive. d) Water is less dense than ice. e) Water has high heat capacity.
e Explanation Water has a high heat capacity. Blood plasma is primarily comprised of water, which provides the ability to moderate temperature changes even under rigorous exercise. This feature of water allows organisms to better maintain their internal temperatures.
Because it is a polar compound, individual water molecules are attracted to one another by ________ bonds, which form because of the attraction between the positive hydrogen atoms and the negative oxygen atoms.
hydrogen
Substances that release _______ ions or take up hydrogen ions when dissociated in water are called ______.
hydroxide, bases
After several generations, one can expect the fish population to have a________portion of orange individuals compared to red individuals.
larger
The ___ value of a solution becomes _______ when more hydrogen ions are released by an acid.
pH, lower
