bio test 1 (ch1-3)

An equal volume (5 mL) of vinegar from a freshly opened bottle is added to each of the following solutions. After complete mixing, which of the mixtures will have the highest pH?

100 mL of household cleanser containing 0.5 M ammonia

Part complete One liter of a solution of pH 4 has how many more hydrogen ions (H+) than 1 L of a solution of pH 9?

100,000 times more

Sulfur has an atomic number of 16 and a mass number of 32. How many electrons are needed to complete the valence shell of a sulfur atom?

2

If a DNA sample were composed of 20% guanine, what would be the percentage of cytosine?

20

Approximately what percentage of human-generated atmospheric CO2 is absorbed by the oceans?

25%

If a DNA sample were composed of 20% adenine, what would be the percentage of cytosine?

30%

If a DNA sample were composed of 15% adenine, what would be the percentage of guanine?

35

How many electron pairs does carbon share in order to complete its valence shell? 12348

4

Phosphorus has an atomic number = 15. How many electrons are in phosphorus' valence shell?

5

What is the DNA complementary sequence to 5' TAACCG 3'?

5' CGGTTA 3'

If one strand of a DNA molecule has the sequence of bases 5'-ATTGCA-3', the other complementary strand would have the sequence

5'-TGCAAT-3'.

Approximately what proportion of the carbon dioxide (CO2) released by burning fossil fuels remains in the atmosphere, contributing to the trapping of heat close to Earth's surface?

50%

In animal populations, DDT causes _____

birth defects

Water molecules are able to form hydrogen bonds with

compounds that have polar covalent bonds.

In eukaryotic cells DNA has the appearance of a _____.

double helix

DNA is composed of building blocks called

nucleotides

What type of bonding or interaction may occur among a broad array of molecules with various physical properties (polar, nonpolar, hydrophilic, hydrophobic)?

van der Waals interactions

The gecko can climb smooth walls due to one type of bond or interaction, whereas a spider can walk on water due to a different kind. Identify each type of bond.

van der Waals, hydrogen bond

When observing the synthesis of a biological macromolecule, more of what should appear?

water

Which property of water allows dogs to cool themselves by panting?

water's high heat of vaporization

The atomic number of nitrogen is 7. Nitrogen-15 is heavier than nitrogen-14 because the atomic nucleus of nitrogen-15 contains how many neutrons?

8

How many molecules of water are needed to completely hydrolyze a polysaccharide that is 10 monomers long?

9

If the results of this study prove correct, taking a fish oil supplement is most likely to benefit which of the following type of person?

A person with an increased risk of heart attack.

Select the most accurate statement about the interaction between a tree and its physical environment.

A tree and its physical environment alter each other

You are a family practitioner. Which of the following patients you see is most likely to need Vitamin D supplements?

A woman with dark brown skin who lives in Michigan

The universal genetic language of DNA is common to virtually all organisms on Earth, however diverse. What is the best explanation for this fact?

All living things share a common genetic language of DNA because they share a common ancestry.

Part complete Which of the following statements is FALSE regarding proteins?

Alzheimer's disease causes proteins in the brain to become improperly folded.

A Part complete A single-celled organism isolated from a deep-sea, hot thermal vent was found to have a cell wall but lacked a nucleus. This organism is most likely a member of which of the following domains?

Archaea

Living things are divided into three different domains. Which of these domains are classified as prokaryotes?

Bacteria and Archaea

How does the formation of covalent bonds differ from the formation of ionic bonds between two atoms?

Covalent bonds involve the sharing of electrons between atoms; ionic bonds involve the transfer of electrons from one atom to the other.

How does RNA differ from DNA?

DNA contains thymine; RNA contains uracil.

Part complete Which of the following best demonstrates the unity among all organisms?

DNA structure and function

Which of the following best summarizes the relationship between dehydration reactions and hydrolysis?

Dehydration reactions assemble polymers, and hydrolysis reactions break down polymers.

Which taxonomic domain includes multicellular photosynthetic organisms?

Eukarya

Part complete Chemical equilibrium is described by which of the following statements?

Forward and reverse reactions continue with no effect on the concentrations of the reactants and products.

Which of the following are considered compounds?

H2O and CH4, but not O2

Part complete How does DNA (deoxyribonucleic acid) encode information?

Information is encoded in the sequence of nucleotides.

Which of the following statements is true regarding cellulose?

It is a primary structural component of plant cell walls

Select the correct statement about the process of scientific inquiry.

It is possible to test hypotheses, such as those involving historical events, without conducting experiments.

According to the video, which of the following describes the impact of Alzheimer's in the United States by the year 2050?

It is projected that there will be 16 million cases by 2050, with an annual health care cost of $1 trillion.

Part complete Which of the following is a requirement for a good scientific hypothesis?

It must lead to testable predictions.

Lemon juice has a pH=2 and vinegar has a pH=4. This means

Lemon juice is 100X more acidic than vinegar

Imagine there is a species-specific fishing regulation that mandates that only adult fish of this species that are 75 cm or longer may be kept; shorter fish must be released. Based on your knowledge of natural selection, how would you predict that the average length of the adult fish population might be affected?

Length would gradually decrease.

Which one of the following statements is true?

Many African governments concluded that the potential long-term health effects of DDT were not as serious as the immediate problem of insect control.

Water has an unusually high specific heat. This is directly related to which of the following?

More heat is required to raise the temperature of water

In her studies of chimpanzee behavior, Jane Goodall collected both qualitative and quantitative data. Which of the following is an example of quantitative data?

Mothers and their infants typically nap for two to three hours each afternoo

You have your blood tested. The results show that you have adequate levels of Vitamin D. Which of the following would likely be best for you?

Not take a Vitamin D supplement.

The following are so diverse that they are not grouped in one Kingdom:

Prostista

Which kingdom comprises mostly unicellular eukaryotes?

Protista

You are a registered dietician. Which of the following clients is most likely to benefit from taking a fish oil supplement?

Someone who rarely eats fish.

Temperatures depend on local geographic conditions. Why is the temperature much cooler in Los Angeles than in San Bernardino?

The cool ocean water buffers temperatures by cooling winds moving inland.and Los Angeles is closer to the ocean than San Bernardino.

In order for a hypothesis to be used in science, which of the following must be true?

The hypothesis is testable and falsifiable

Part complete Why are hydrocarbons insoluble in water?

The majority of their bonds are nonpolar covalent carbon-to-hydrogen linkages.

The nucleus of a nitrogen atom contains 8 neutrons and 7 protons. Which of the following is a correct statement concerning nitrogen?

The nitrogen atom has a mass number of 15 and an atomic number of 7.

Which statement about the energy radiated from the ears of a rabbit cooling itself is accurate?

The original source of the energy was the sun.

Imagine that you have just discovered a new multicellular, microscopic organism that swims in ponds. It is propelled by cilia. What can you say about the evolutionary relationships of this organism?

The presence of cilia shows that it shares a common ancestor with Paramecium and humans

Which of the following statements is true of both starch and cellulose?

They are both polymers of glucose.

Part complete Which of the following statements concerning saturated fats is true?

They are generally solid at room temperature.

Which of the following statements regarding lipids is true?

They are insoluble in water.

What is true for double bonds?

Unsaturated fats have double bonds and are associated with good cardiovascular health.

Why is milk often fortified with Vitamin D?

Vitamin D is associated with calcium uptake.

All the organisms on your campus make up __________.

a community

Scientists have synthesized a new artificial compound to mimic the effects of a hormone that influences sexual behavior. Which of the following compounds is most likely to mimic the effects of the hormone?

a compound with the same three-dimensional shape as part of the hormone

All the individuals of a particular species living within the bounds of a specified area are collectively described by which of the following terms?

a population

DNA is made up of deoxyribose sugar, phosphate (a functional group), and _______

adenine, cytosine, guanine, thymine

Which property of water allows a paper towel to pick up a puddle of water?

adhesion of water molecules to other kinds of molecules

Normal hemoglobin is a tetramer, consisting of two molecules of ββ-globin and two molecules of αα-globin. In sickle-cell disease, because of a single amino acid change, the mutant hemoglobin tetramers associate with each other and assemble into large fibers. Based on this information alone, we can conclude that sickle-cell hemoglobin exhibits

altered primary structure and altered quaternary structure; the secondary and tertiary structures may or may not be altered.

Changing a single amino acid in a protein consisting of 433 amino acids would

always alter the primary structure of the protein and sometimes alter its tertiary structure or function.

Part complete Which of the following is a monomer used to build a biological polymer?

amino acid

An ionic bond involves _____.

an attraction between ions of opposite charge

All the living organisms in a particular area along with all the nonliving aspects of the environment with which organisms interact are collectively described by which of the following terms?

an ecosystem

Oxygen has an atomic number of 8 and a mass number of 16. What is the atomic mass of an oxygen atom?

approximately 16 daltons

Which of the following types of cells lack(s) a nucleus?

archaea

Ibuprofen is a drug commonly used to relieve inflammation and pain. It is a mixture of two enantiomers, which are molecules that

are mirror images of one another.

All lipids

are poorly water soluble.

Lactose, a sugar in milk, is composed of one glucose molecule joined by a glycosidic linkage to one galactose molecule. How is lactose classified?

as a disaccharide

Part complete All of the organisms living in a particular ecosystem are collectively known as a(n

biological community.

Which of the following represents the correct hierarchy of biological organization from large scale to smaller scale?

biosphere →→ ecosystems →→ communities →→ populations →→ organisms

Which four of the 92 naturally occurring elements make up approximately 96% of the mass of the human body?

carbon, hydrogen, nitrogen, oxygen

Which is not a function of proteins?

carry the code for translation from the nucleus to the ribosome

The actions of an organism are based on activities of ________

cells

Part complete The term insoluble fiber on food packaging generally refers to which of the following carbohydrates?

cellulose

Part complete Many properties of living things involve the transfer and transformation of energy and matter. For example, plant chloroplasts convert energy from sunlight to which of the following forms of energy or matter?

chemical energy

Which of the following molecules lacks amino acids?

cholesterol

Which properties of water are most important for the movement of water up the tree?

cohesion and adhesion

What are the four emergent properties of water that are important for life?

cohesion, moderation of temperature, expansion upon freezing, solvent properties

So, one water molecule is hold together by

covalent bonds

If you were a fish in Minnesota, for which property of water would you be most grateful?

decreased density when solid

What is a common chemical reaction mechanism by which cells make polymers from monomers?

dehydration reactions

The variation observed among the finches Darwin collected from the Galápagos Islands illustrate which of the following principles associated with the evolution of species?

descent with modification

What structural feature makes the 20 common amino acids different from one another?

different side chains (R groups) attached to an αα carbon

If you see radioactive isotopes in a laboratory that deals with biological samples, what is the least likely reason they are present?

disinfecting wounds

Correct the following statement: "A double ionic bond can occur if the valence shells of the two participants allow for sharing two electrons."

double covalent bond can occur if the valence shells of the two participants allow for sharing four electrons."

Part complete The sequence 5'-GAACGA-3' may be found in which of the following?

either DNA or RNA

Part complete A substance that cannot be broken down into other substances by ordinary chemical procedures is a(n) _____

element

Part complete No amino acid molecule by itself can speed up or catalyze reactions between other molecules; however, when amino acids are joined together to make a protein with catalytic properties, the new structure (enzymatic protein) can speed up the rate of a specific chemical reaction. What does this illustrate?

emergent properties

Isomers of a compound have the same chemical formula and therefore the same function

false

DDT is _____-soluble so it accumulates in _____.

fat ... milk

If you were asked to chose a lipid subunit, which would you choose?

fatty acid

What do the bubbles shown on these leaves indicate?

formation of covalent bonds

Which of the following solutions would require addition of the greatest amount of base to bring the solution to neutral pH?

gastric juice at pH 2

The entire set of genetic information in a cell or an organism is referred as a ______

genome

Which falls outside the lipids?

glucose

Which polysaccharide has the greatest number of branches?

glycogen

Which of the following descriptions constitutes a controlled experiment?

growing one set of 10 seedlings under white light and one set of the same type of seedlings under red light and measuring their growth over a period of two weeks

Part complete Charles Darwin proposed that "descent with modification" resulted when organisms of a particular species become adapted to their environment because they possess which of the following characteristics?

heritable traits that enhance their survival and reproductive success in the local environment

Humans can digest starch but not cellulose because

humans have enzymes that can hydrolyze the αα glycosidic linkages of starch but not the ββ glycosidic linkages of cellulose.

What name is given to the bond between water molecules?

hydrogen

And water molecules connect with each other via

hydrogen bonds

In an aqueous solution, water molecules associate with one another through which of the following?

hydrogen bonds

Part complete Which type of interaction stabilizes the αα helix and the ββ pleated sheet structures of proteins?

hydrogen bonds

Water becomes less dense when it freezes due to

hydrogen bonds

Water has special properties, including high cohesion, high surface tension, and the ability to absorb large amounts of heat per unit of mass. What kind of bonds between water molecules give water these special properties?

hydrogen bonds

For what is water most important when digesting food?

hydrolysis reactions

Defensive proteins are manufactured by the _____ system

immune

In salt, what is the nature of the bond between sodium and chlorine?

ionic

Which of the following is a trace element required by all living organisms?

iron

The difference between the sugar in DNA and the sugar in RNA is that the sugar in DNA

is a five-carbon sugar, and the sugar in RNA is a six-carbon sugar.

You are asked whether a sample came from a living thing. Chemical analysis shows that it consists mostly of calcium and sulfur, so you say that

it did not, since living things contain more carbon and oxygen than most other elements.

When two carbon atoms are joined by a double bond, the carbons and atoms bound to them form which of the following structures?

lane

The primary source of energy for producers in an ecosystem is

light energy

Which of the following correctly describes the forms by which energy flows through an ecosystem from entry to exit?

light →→ chemical →→ heat

Which provides the most compact energy storage?

lipids

Which scientific study would represent an example of a systems biology approach?

measuring the effect of an invading insect that eats oak leaves on the numbers of oak trees and on any subsequent changes in the number and types of decomposer fungi in the soil

Imagine that you are examining the structure of an extraterrestrial organism's cells. You separate various components, finding one that mixes poorly with water. This is probably from the organism's

membranes

A(n) _____ refers to two or more atoms held together by covalent bonds.

molecule

What is the correct order (from small to large) in a living cell or an organism?

molecules, organism, population, communities, biosphere

From what are polysaccharides made?

monosaccharides

Over time, the lineage that led to modern whales shows a change from four-limbed land animals to aquatic animals with two limbs that function as flippers. This change is best explained by which of the following concepts or processes?

natural selection

Part complete The sequence 5'-GAACUT-3' may be found in which of the following?

neither DNA nor RNA

Hydrophobic substances such as vegetable oil are

nonpolar substances that repel water molecules.

If you located a single-stranded piece of nucleic acid in a cell, what would it be made of?

nucleotides

Part complete Two atoms that have the same mass number must have the same

number of protons plus neutrons.

Part complete Which of the following statements is a distinguishing characteristic of fungi?

obtaining nutrients by absorbing them from the environment

Where in the structure of a protein would glutamic acid (hydrophilic) be mostly likely?

on the exterior surface of the protein

A covalent bond is likely to be polar when

one of the atoms sharing electrons is much more electronegative than the other atom.

Which of the following terms describes membrane-enclosed components of cells that carry out specialized functions?

organelles

Which of these does NOT contain a structural protein?

ovalbumin

The tertiary structure of a polypeptide is the

overall three-dimensional shape of a fully folded polypeptide

Complete the analogy: Covalent bonds are to ionic bonds as a wooden board is to

paper

Which bonds maintain the primary structure of a protein?

peptide bonds

Molecules that are soluble in water have which type of bond?

polar covalent bond

In a single molecule of water, two hydrogen atoms are bonded to a single oxygen atom by

polar covalent bonds

A group of organisms from one species living together in a given environment is referred to as

population

Which level of protein structure is most immediately encoded in DNA?

primary

In sickle cell anemia, the change of one nucleotide lead to alterations in the:

primary, secondary, tertiary and quaternary structures of hemoglobin

If cells are grown in a medium containing radioactive 35S, which of these molecules will be radioactively labeled?

proteins

If you observed an extraterrestrial organism that was mostly composed of water, and you saw that it gradually lost water during warmer weather, you would guess that the function of the water loss was to

reduce temperature

Part complete Investigating the molecular structure of DNA in order to understand the chemical basis of inheritance is an example of which approach utilized in the study of biology?

reductionism

Which sugar is most important for making RNA?

ribose

In a normal cellular protein, where would you expect to find a hydrophilic amino acid such as asparagine?

rior surface of the protein, interacting with water

The αα helix and ββ pleated sheet are examples of which level of protein structure?

secondary

A covalent bond is formed by

sharing of a pair of electrons between two atoms.

The following lipid group does not contain glycerol:

steroids

Which is least important for metabolism?

structural protein

For which of the following could genomics be used?

studying disease, conservation work, predicting future medical problems, evolutionary studies

Which of the following is the smallest carbohydrate?

sucrose

Polysaccharides, triacylglycerols, and proteins are similar in that they are

synthesized from subunits by dehydration reactions.

What is incorrect about the following statement? "The tRNA sequence reads ATGCCATGG..."

tRNA has U in place of T.

A controlled experiment is one that __________

tests experimental and control groups in parallel

Which of the following structures is formed by the atoms involved when a carbon atom is bound by single covalent bonds to four other atoms?

tetrahedron

The fact that the DNA structure is anti-parallel means

that it has two strands but they run in opposite directions

All the living things on Earth along with all the places where life exists are collectively described by which of the following terms?

the biosphere

If the cytoplasm of a cell is at pH 7, and the interior of an organelle is pH 8, this means that

the concentration of hydrogen ions is tenfold higher in the cytoplasm than in the organelle.

Part complete The chemical behavior of an atom depends primarily upon which of the following?

the number of electrons in the valence shell

Lactase is an enzyme composed of a single polypeptide that hydrolyzes the disaccharide lactose to produce monosaccharides. The optimal pH for lactase activity is 6. Transfer of lactase to pH 5 results in a substantial decrease in enzyme activity, likely due to the disruption of

the secondary and tertiary structures of the enzyme.

Which of the following attributes is common to both prokaryotic cells and eukaryotic cells?

the use of an external membrane to regulate the passage of materials from and to surroundings

The energy in ATP is released when the third phosphate breaks a part from the molecule producing ADP + inorganic phosphate

true