BIO exam 1

Which of the following best summarizes the relationship between dehydration reactions and hydrolysis? -Dehydration reactions split water molecules and add hydroxyl groups to polymers, and hydrolysis reactions remove hydroxyl groups from polymers. -Dehydration reactions assemble polymers, and hydrolysis reactions break down polymers. -Dehydration reactions create monomers, and hydrolysis reactions assemble polymers. -Dehydration reactions break down polymers, and hydrolysis reactions create monomers.

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

A pH of 6 represents: -a low concentration of hydrogen ions -a high concentration of hydroxy ions -an equal amount of hydrogen and hydroxy ions. -a high concentration of hydrogen ions -a high concentration of oxygen ions

-a high concentration of hydroxy ions

Slightly negative charge at one end of one water molecule is attached to the slight positive charge of another water molecule. What is this attraction called? -a covalent bond -a van der Waals interaction -a hydrogen bond -an ionic bond -a hydrophilic bond

-a hydrogen bond

The process of science involves testing which of the following? -a conclusion -a hypothesis -a data set -an observation -a control group

-a hypothesis

What results from an unequal sharing of electrons between atoms? -a polar covalent bond -a nonpolar covalent bond -an ionic bond -a hydrophobic interaction

-a polar covalent bond

Which of the following is a monomer used to build a biological polymer? -triglyceride -disaccharide -DNA -amino acid

-amino acid

Lactose, a sugar in milk is composed of one glucose molecule joined by a glyosidic linkage to one galactose molecule. How is lactose classified? -as a polysaccharide -as a hexose -as a monosaccharide -as a pentose -as a disaccharide

-as a disaccharide

Charles Darwin proposed that "descent with modification" resulted when organisms of a particular species become adapted to their environment because they possess -heritable traits that enhance their survival and decrease their reproductive success in the local environment. -nonheritable traits that enhance survival and decrease their reproductive success in the local environment. -heritable traits that enhance their survival and their reproductive success in the local environment. -nonheritable traits that enhance survival and their reproductive success in the local environment.

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

Hydrophobic substances such as vegetable oil are -nonpolar substances that have an attraction for water molecules. -charged molecules that hydrogen-bond with water molecules. -polar substances that have an affinity for water. -nonpolar substances that repel water molecules. -polar substances that repel water molecules.

-nonpolar substances that repel water molecules.

From the atomic mass, one can deduce the number of ________ in each atom of an element. -electrons -protons plus electrons -protons -neutrons -protons plus neutrons

-protons plus electrons

Which of the following is an example of a dehydration reaction? -the reaction of a fat with glycerol, forming fatty acids with the release of water -the reaction of two monosaccharides, forming a disaccharide with the release of water -the reaction of a fat, forming glycerol and fatty acids with the release of water -the reaction of two amino acids, forming a peptide bond with the consumption of water

-the reaction of two monosaccharides, forming a disaccharide with the release of water

A controlled experiment is one in which -there are at least two groups, one of which does not receive the experimental treatment. -the experiment proceeds at a slow pace to guarantee that the scientist can carefully observe all reactions and process all experimental data. -there are at least two groups, one differing from the other by two or more variables. -the experiment is repeated many times to ensure that the results are accurate.

-there are at least two groups, one of which does not receive the experimental treatment.

Which of the following statements regarding lipids is true? -they generally contain nitrogen. -they are made from glycerol and amino acids. -a gram of lipid stores less energy than a gram of carbohydrate. -they are insoluble in water.

-they are insoluble in water.

An atom has 6 electrons in its outer shell. How many unpaired electrons does it have? -0 -6 -2 -4 -2 or 4

2

How many electron pairs does carbon share in order to complete its valence shell? -2 -8 -4 -1 -3

4

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? -7 -8 -6 -14 -12

8

The process by which a cell engulfs a foreign particle is known as: A. endosymbiosis B. phagocytosis C. hydrolysis D. membrane synthesis

B. phagocytosis

Which of the following organisms is a prokaryote? -amoeba -influenza A virus -charophyte algae -E. coli

E. coli

What property makes cholesterol a lipid? It is not essential to the functioning of cells, and is only harmful to human health. It functions as a hormone that can pass through the cell membrane. Its carbon skeleton is mostly C-C and C-H bonds, with very little O. It is a polar and hydrophilic compound. It is made of fatty acids.

Its carbon skeleton is mostly C-C and C-H bonds, with very little O.

What kinds of molecules pass through a cell membrane most easily? Small hydrophobic small ionic large polar large and hydrophilic

Small hydrophobic(non polar)

Which of the following is the best description of a control for an experiment? -The control group is kept in an unchanging environment. -the control is left alone by the experimenters. -the control group is exposed to only variable rather than several -the control group is matched with the experimental group except for the one experimental variable.

The control group is kept in an unchanging environment.

Which of the following statements best distinguishes hypotheses from theories in science? -Theories are proved true; hypotheses are often contradicted by experimental results. -Hypotheses usually are relatively narrow in scope; theories have broad explanatory power. -Hypotheses are guesses; theories are correct answers. -Theories are hypotheses that have been proved.

Theories are proved true; hypotheses are often contradicted by experimental results.

A pH of 6 represents...

a high concentration of hydrogen ions

bacteria that lack fimbriae are less likely to ____ -adhere to cell surfaces -swim through bodily fluids -synthesize proteins -retain the ability to divide

adhere to cell surfaces

Why are plant oils liquid at room temperature while animal fats are solid? -cholesterol in animal fats makes it solid -animal fat is saturated and more dense -plant oils has a different polarity than animal fat -animal fat has branched-chain hydrocarbons

animal fat is saturated and more dense

The evolution of various eukaryotic cells most likely involved the ingestion of a photosynthetic bacterium that became chloroplasts the ingestion of a bacterium that became mitochondria both the ingestion of a bacterium that became mitochondria and the ingestion of a photosynthetic bacterium that became chloroplasts the ingestion of a bacterium that became the nucleus No answer text provided.

both the ingestion of a bacterium that became mitochondria and the ingestion of a photosynthetic bacterium that became chloroplasts

The _____ is the basic unit of life. -organism -cell -tissue -organ

cell

what is the difference between covalent bonds and ionic bonds? -covalent bonds are formed between atoms to form molecules; ionic bonds are formed between atoms to form compounds. -covalent bonds involve the sharing of electrons between atoms; ionic bonds involve the electrical attraction between atoms. -covalent bonds involve the sharing of electrons between atoms; ionic bonds involve the sharing protons between atoms. -covalent bonds involve the transfer of electrons between atoms; ionic bonds involve the sharing of electrons between atoms. -covalent bonds involve the sharing of pairs of electrons between atoms; ionic bonds involve the sharing single electrons between atoms.

covalent bonds involve the sharing of electrons between atoms; ionic bonds involve the electrical attraction between atoms

There are 20 different amino acids. What makes one amino acid different from another? -different side chains (R groups) attracted to an a carbon -different asymmetric carbons -different side chains (R groups) attached to the carboxyl carbon -different side chains (R groups) attached to the amino groups

different side chains (R groups) attached to the amino groups

prokaryotes depend on _____ to obtain some materials and to get rid of wastes. -ribosomes -flagella -cell division -diffusion

diffusion

Molecules with which functional groups may form polymers via dehydration reactions? A) hydroxyl groups B) either hydroxyl or carboxyl groups C) carbonyl groups D) either carbonyl or carboxyl groups E) carboxyl groups

either hydroxyl or carboxyl groups

Natural means: -Safe and effective -non-toxic, non-harmful -promotes health and vitality -existing in nature

existing in nature

A molecule with the chemical formula C3H8O3 is probably a -hydrocarbon -lipid -glycerol -monosaccharide

glycerol

A + H20-----> B + C is an example of -hydrolysis -dehydration -condensation -polymerization -hyperpolarization

hydrolysis

Submerging a red blood cell in distilled water (100% water) will result in lysis of the cell. the cell becoming turgid. plasmolysis of the cell. the cell becoming flacid. channel proteins.

lysis of the cell.

Which organelle found in plant cells contains its own DNA and ribosomes? Golgi apparatus rough ER mitochondrion central vacuole peroxisome

mitochondrion

A molecule with the chemical formula C6H12O6 is probably a -hydrocarbon -lipid -glycerol -monosaccharide

monosaccharide

A covalent bond is likely to be polar when -oxygen is one of the two atoms sharing electrons. -the two atoms sharing electrons are the same element. -the two atoms sharing electrons are equally electronegative. -one of the atoms sharing electrons is much more electronegative than the other atom. -the two atoms sharing electrons are different elements.

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

Which would you find in eukaryotic cells, but not in bacteria? flagella plasma membrane ribosomes organelles DNA

organelles

Which type of bonds are formed in the synthesis of a protein's primary structure? glycosidic bonds (linkages) hydrogen bonds phosphodiester bonds (linkages) peptide bonds disulfide bond

peptide bonds

Peroxisomes got their name because hydrogen peroxide is: -used in their detoxification reactions -produced during their oxidation reactions -incorporated into their membranes -a cofactors for the organelles' enzymes

produced during their oxidation reactions

The function of ribosomes is to manufacture nucleic acids proteins cellulose glycogen lipids

proteins

Which of the following is both in eukaryotic and prokaryotic cells? -nucleus -mitochondrion -vacuoles -ribosomes

ribosomes

Which of these is a carbohydrate? -roach's exoskeleton -salami -hamburger -canola oil -water

roach's exoskeleton

When viewing a specimen through a light microscope, scientists use _____ to distinguish the individual components of cells. -a beam of electrons -radioactive isotopes -special stains -high temperatures

special stains

Trypsin breaks down proteins and works with a optimal pH of around 7. Which of these areas of the GI tract would be most conductive to pepsin functioning? -mouth -stomach -small intestine -large intestine -colon

stomach

Submerging a plant cell in distilled water (100% water) will result in the cell becoming turgid (~ stiff). the cell becoming flaccid (~ limp). bursting of the cell. plasmolysis of the cell. lysis of the cell membrane.

the cell becoming turgid (~ stiff).

Why are hydrocarbons insoluble in water? -the majority of their bonds are non polar covalent carbon-to-hydrogen linkages. -they are hydrophilic. -they exhibit considerable molecular complexity and diversity -the majority of their bonds are polar covalent carbon-to-hydrogen linkages.

the majority of their bonds are polar covalent carbon-to-hydrogen linkages

Which of the following is surrounded by two phospholipid bilayers? -the ribosomes -the vesicles -the cytoplasm -the nucleoplasm

the nucleoplasm

How are nucleotides added to a growing DNA strand during dehydration? -the terminal 3' carbon of the growing strand adds to the 5' carbon of the new nucleotide -the terminal 5' carbon of the growing strand adds to the 3' carbon of he new nucleotide.

the terminal 3' carbon of the growing strand adds to the 5' carbon of the new nucleotide

In plant cells, the function of the lysosomes is carried out by __________. -vacuoles -peroxisomes -ribosomes -nuclei

vacuoles

A scientific theory is: an educated guess -a random idea that scientist came up with on the spur of the moment -widely accepted in the scientific community as being true -a tested and accepted hypothesis -an opinion

widely accepted in the scientific community as being true