Chapter 1-3: Biology: Exploring Life, Chemical Basis of Life, Molecules of Cells

The mass of the isotope of element changes due to change in the number of ______.

neutrons

Which of the following solutions is the weakest acid? A solution with a ___ A) pH 2.4 B) pH 5.2 C) pH 6.4 D) pH 8.6 E) pH 10.1

pH 6.4

All members of the same species that populate a certain area are called a(n):

population

The number of__________ gives the element its identity. It is most stable.

protons

Particles that carry either a positive (+) or negative (-) charge are called _______

ions

Covalent Bond:

Chemical bond between atoms formed by sharing a pair of valence electrons.

Choose the CORRECT order (1-5) of increasing complexity/organization.

(1) cells, (2) tissues, (3) organs, (4) organ systems, (5) organism

How many electrons does an atom with an atomic number of 12 needs to have to be electrically neutral?

12 electrons

Which of the following solutions is the weakest acid? A solution with a ___ A) pH 2.4 B) pH 5.2 C) pH 6.4 D) pH 8.6 E) pH 10.1

6.4

How does scientific information in peer-reviewed journals differ from that in newspapers? A) Information is more technical; readers usually require a background in the field in order to understand the article. B) The article is written by a reporter, not the researcher. C) Articles often include political, ethical, and economic ramifications of the scientific findings. D) Information is less in-depth and easily understood by the average reader. E) Information is not approved by other scientists before its publication.

A) Information is more technical; readers usually require a background in the field in order to understand the article.

Amino acids include a side group as well as ______. A) a central carbon, a hydrogen atom, an amino group, and a carboxyl group B) a central carbon, a hydrogen atom, a hydroxyl group, and a carbonyl group C) a central hydrogen, a nitrogen atom, an amino group, and a carboxyl group D) a central hydrogen, a nitrogen atom, a hydroxyl group, and a carbonyl group E) a central nitrogen, a carbon atom, an amino group, and a carbonyl group

A) a central carbon, a hydrogen atom, an amino group, and a carboxyl group

A specific stretch of DNA that programs the amino acid sequence of a polypeptide is a ______. A) gene B) protein C) nucleotide D) nucleic acid E) enzyme

A) gene

As water freezes ______. A) its molecules move farther apart B) it absorbs energy from the surrounding environment C) it cools the surrounding environment D) its hydrogen bonds break apart

A) its molecules move farther apart

The role of a control in an experiment is to A) provide a basis of comparison to the experimental group. B) prove that a hypothesis is correct. C) ensure repeatability. D) prove that a hypothesis is correct and ensure repeatability. E) None of the choices are correct.

A) provide a basis of comparison to the experimental group.

What is the difference between a tissue and an organ system? A) The tissue level of organization is more inclusive than the organ system level. B) Tissues are not composed of cells; organ systems are composed of cells. C) A tissue cannot exist unless it is a component of an organ system, whereas an organ system can exist independently of tissues. D) An organ system includes tissues. E) Tissues are not considered to be living; organ systems are considered to be living.

An organ system includes tissue.

What is the fundamental difference between covalent and ionic bonding? A) In a covalent bond, the partners have identical electronegativity; in an ionic bond, one of them is more electronegative. B) In a covalent bond, the partners share a pair of electrons; in an ionic bond, one partner captures an electron from the other. C) In covalent bonding, both partners end up with filled outer electron shells; in ionic bonding, one partner does and the other does not. D) Covalent bonding involves only the outer electron shell; ionic bonding also involves the next inner electron shell. E) Covalent bonds form between atoms of the same element; ionic bonds, between atoms of different elements.

B) In a covalent bond, the partners share a pair of electrons; in an ionic bond, one partner captures an electron from the other.

In the following reaction, galactose is a ______. galactose + glucose → lactose + water A) polysaccharide B) monomer C) lipid D) polymer E) protein

B) monomer

The lower the pH of a solution, the ______. A) greater the number of oxygen atoms B) more acidic the solution C) less toxic the solution D) higher the OH— concentration E) more basic the solution

B) more acidic the solution

Sugar dissolves when stirred into water. The sugar is the ______, the water is the ______, and the sweetened water is the ______. A) solution . . . solvent . . . solute B) solute . . . solvent . . . solution C) solvent . . . solute . . . solution D) solution . . . solute . . . solvent E) solvent . . . solution . . . solute

B) solute . . . solvent . . . solution

An antibiotic kills 99.9% of a bacterial population. You would expect the next generation of bacteria A) to be just as susceptible to that antibiotic as was the previous generation. B) to be more resistant to that antibiotic. C) to die out due to the drastic decrease in population size. D) to be more contagious than the prior generation. E) All of the choices are correct.

B) to be more resistant to that antibiotic

Hydrogen bonding in water causes the water to: A. boil at a lower temperature than expected B. be less dense as ice than as liquid water C. absorb heat with large immediate change in temperature D. release heat with large immediate change in temperature E. shrink as temperature approaches 0°C

B. be less dense as ice than as liquid water

The class of organic compounds that are insoluble in water is: A. sugars B. lipids C. acids D. salt E. albumin

B. lipids

Which of the following is an acid? A) NaOH B) NaCl C) HCl D) H2O E) CH4

C) HCl

Pure,freshly- distilled water has a pH of 7. This means that A) there are no H+ ions in the water. B) there are no OH- ions in the water. C) the concentration of H+ ions in the water equals the concentration of OH- ions in the water. D) the concentration of H+ ions in the water is 7 times the concentration of OH- ions in the water. E) The concentration of OH-ions in the water is 7 times the concentration of H+ ions in the water.

C) The concentration of H+ ions in the water = the concentration of OH- ions in the water

Proteins are polymers constructed from ______ monomers. A) 5-carbon ring B) hydrocarbon C) amino acid D) nucleotide E) fatty acid

C) amino acid

Destruction of a protein's shape is called ______. A) anabolism B) hydrolysis C) denaturation D) a dehydration reaction E) hydrogenation

C) denaturation

31.When a base is added to a buffered solution, the buffer will ______. A) donate OH— ions B) accept water molecules C) donate H+ ions D) form covalent bonds with the base E) accept H+ ions

C) donate H+ ions

A student needs information from the National Institutes of Health, a government agency. Which of the following endings should he or she look for in the Internet address? A) edu B) com C) gov D) nih E) org

C) gov

The hydrogen atoms of a water molecule are bonded to the oxygen atom by __________ bonds, whereas neighboring water molecules are held together by __________ bonds. A) hydrogen . . . ionic B) hydrogen . . . polar covalent C) polar covalent . . . hydrogen D) ionic . . . covalent E) polar covalent . . . ionic

C) polar covalent . . . hydrogen

A protein's function is dependent on its ______. A) pH B) temperature C) shape D) size E) weight

C) shape

Which of the following characteristics of protein will remain intact if the protein is denatured? A) the shape of the protein B) the function of the protein C) the number of amino acids in the protein D) the binding properties of the protein

C) the number of amino acids in the protein

A scientist performs a controlled experiment. This means that A) the experiment is repeated many times to ensure that the results are accurate. B) the experiment proceeds at a slow pace to guarantee that the scientist can carefully observe all reactions and process all experimental data. C) two experiments are conducted, one differing from the other by only a single variable. D) two experiments are conducted, one differing from the other by two or more variables. E) one experiment is performed, but the scientist controls the variables.

C) two experiments are conducted, one differing from the other by only a single variable

______ is a hydroxyl group. A) —SH B) —NH2 C) —OH D) -COOH E) —H

C) —OH

Which of the following correctly describes a glucose molecule? A. It is a pentose monosaccharide. B. It is pentose disaccharide. C. It is a hexose monosaccharide. D. It is a hexose disaccharide. E. It is a complex polysaccharide.

C. It is a hexose monosaccharide.

Non-Polar Covalent Bond:

Covalent bond formed by an equal sharing of electrons by atoms.Molecules of the same element usually have non-polar covalent bond.

Polar Covalent Bond:

Covalent bond formed by unequal sharing of electrons between atoms. shared electrons spend more time around the more electronegative atom. In H2O for example,the oxygen is strongly electronegative , so negatively charged electrons spend more time around the Oxygen rather than the Hydrogen. This causes the oxygen to have a slight negative charge and the hydrogens to have a slight positive charge.

The criteria for classification of animals, plants, and fungi are based largely on A) the organism's life cycle. B) the structure or body plan of the organism. C) the mode of nutrition of the organism. D) All of the above are correct.

D) All of the above

The Internet has been used as a rapid means to obtain information, including scientific ideas, but generally is less reliable than print media because A) at present, the Internet is less regulated than broadcast and print media. B) anyone can post "scientific" information, regardless of whether the information is misleading or not true. C) individuals and/or groups may post information to promote their own personal interests rather ideas that have been tested through the scientific process. D) All of the above are correct.

D) All of the above are correct.

Evolution by natural selection relies upon A) individual variation B) overproduction of offspring C) struggle for existence. D) All of the choices are correct.

D) All of the choices are correct A) individual variation B) overproduction of offspring C) struggle for existence.

Which one of the following statements is correct? A) Genes are proteins that produce DNA. B) Each organism has its own unique DNA code. C) DNA relies upon five different building blocks as the alphabet of inheritance. D) Differences among organisms reflect different nucleotide sequences in their DNA. E) Each DNA molecule is a single strand of nucleotides.

D) Differences among organisms reflect different nucleotide sequences in their DNA.

A farmer wants to improve crop yield in his fields by testing the effectiveness of a new pesticide available on the market. Which of the following is the best control for this experiment? A) a higher concentration of new pesticide used on the control field than the experimental field B) more shade on the control field than the experimental field C) less new pesticide used on the control field than the experimental field D) more water on the control field than the experimental field E) no new pesticide used on the control field; new pesticide used only on the experimental field

E) no new pesticide used on the control field; new pesticide used only on the experimental field

Nucleic acids are polymers of ______ monomers. A) monosaccharide B) hydrocarbon C) fatty acid D) DNA E) nucleotide

E) nucleotide

A base ______. A) removes H2O molecules from a solution B) decreases the pH of a solution C) adds HOH molecules to a solution D) removes OH— ions from a solution E) removes H+ ions from a solution

E) removes H+ ions from a solution

A glycerol with three fatty acids attached is referred to as a ______. A) prostaglandin B) nucleic acid C) steroid D) protein E) triglyceride

E) triglyceride

In the Domain classification system, which group of organisms contains multicellular photosynthesizers?

Eukarya

Organisms that are not prokaryotes are in the Domain

Eukarya

Which of the following taxa applies to humans?

Mammals

Ionic bond:

The complete transfer of valence electron (s) between atoms. It is a type of chemical bond that generates two oppositely charged ions. In ionic bonds, the metal loses electrons to become a positively charged cation, whereas the nonmetal accepts those electrons to become a negatively charged anion.

Which of the following is/are properties of life?

a complex organization, the ability to take in energy and use it, the ability to respond to stimuli from the environment, the ability to reproduce

Members of the Kingdom Animalia

are composed of cells that lack a cell wall

The network or sphere of life on the planet is called the:

biosphere

Each triglyceride molecule consists of glycerol and fatty acid in the following proportions: a. Three glycerols and one fatty acids b. Two glycerols and two fatty acids c. One glycerol and three fatty acids d. One glyerol and one fatty acid e. None of the above

c. One glycerol and three fatty acids

Ions are produced by the loss or gain of____________.

electrons

The nucleus of an atom does not contain___________.

electrons

The ultimate source of energy flowing into nearly all ecosystems is

sunlight

To be scientifically valid, a hypothesis must be

testable and falsifiable