Chapter 2 Connect Microbiology Lecture

Compared to a solution of pH 9, a solution of pH 7 is:

100 times more acidic.

What is the maximum number of electrons in the first energy shell of an atom?

2

Which of the following is a characteristic of double-stranded DNA?

2 nanometers in width, 10 base pairs per turn and 0.34 nanometers per basepair

Select the number of phosphates present in a molecule of ATP

3

What is the maximum number of electrons in the second energy shell of an atom?

8

Which of the following represents a synthesis reaction?

A + B → AB

Which of the following represents a reversible reaction?

AB + XY ↔ AY + XB

One nucleotide contains one

All of the choices are correct. - Phosphate - Pentose sugar. - Nitrogen base.

Characteristics shared by all cells include

All of the choices are correct. - a membrane serving as a cell boundary. - the possession of genetic information. - the presence of cellular fluid.

Choose the term that represents the smallest particle of an element that retains all of the properties of that element

Atom

A covalent bond is formed between an anion and a cation.

False

A new organism was identified that contained arsenic in place of phosphate in its DNA double helix structure. Based upon this information alone, it can be determined that this change will greatly alter the information encoded by this genetic material.

False

Because of their simple cell structure, bacterial and archaeal cells are very limited in their cellular capabilities as compared to more complex eukaryotic cells

False

Electrons that participate in chemical bonding are typically located closest to the nucleus.

False

Nucleic acids have primary, secondary, tertiary, and quaternary levels of organization.

False

The concentration of a solution expresses the amount of solvent present.

False

Tincture of iodine is prepared by dissolving iodine in alcohol. In this solution, iodine is the solvent.

False

Water molecules are nonpolar molecules.

False

Which of the following DNA molecules is the most stable?

GCGTGCAC CGCACGTG

Anything that occupies space and has mass is called

Matter

Choose the term that identifies the type of bond that maintains the primary structure of a protein.

Peptide bond

Alpha helices and beta pleated sheets are examples of this level of protein structure:

Secondary

All atoms in an element have the same number of protons

True

Asymmetrical spacing of the backbones of the DNA double helix generates major and minor grooves.

True

Doubled-stranded DNA consists of two antiparallel strands, meaning that one strand is oriented in the 5' to 3' direction, while the other is oriented in the 3' to 5' direction.

True

If solution A has a lower pH compared to solution B, then solution A is more acidic than solution B.

True

Polar molecules have more reactivity compared to nonpolar molecules.

True

The most important outcome of polypeptide intrachain bonding and folding is the unique shape of the protein.

True

The only part of an amino acid that differs from other amino acids is its R group.

True

Viruses are not considered living organisms because they lack cellular structure and require a host cell for life cycle completion.

True

Burning coal produces sulfur dioxide in the atmosphere. When combined with precipitation that falls into bodies of water, this leads to:

a decrease in the pH level of the water.

C6H12O6 + C6H12O6 → C12 H22O11 + H2O represents

a dehydration synthesis.

Which of the following is not a pyrimidine?

adenine

A capillary tube is used to acquire a small blood sample for CBC (complete blood count) analysis. Suction is not required to transfer the blood from the fingertip prick to the tube in part due to:

adhesive forces between the water molecules and the glass particles of the tube.

The electrons of an atom are

always equal to the number of protons

The building blocks of an enzyme are

amino acids.

Starch is the primary storage food for all of the following except

animals.

Ionic compounds

are hydrophilic.

Polar molecules are composed of covalently bonded

atoms of different electronegativity

Cations are

capable of forming ionic bonds with anions

Organic chemicals always have a basic framework of the element _____ bonded to other atoms.

carbon

Which pertains to DNA but not to RNA?

contains thymine

Choose the tern which names the type of bond found between carbon and hydrogen in most biological molecules.

covalent bond

Substances that release ions when dissolved in water and conduct electricity are

electrolytes.

The subatomic particles that surround the nucleus are the

electrons

What part of a phospholipid comprise the hydrophobic tails?

fatty acids

Microscopic analysis of a cell reveals the presence of ribosomes. Based upon this information alone, it can be determined that:

further information is needed to determine if it is either a bacterial, archaeal, or eukaryotic cell.

All of the following are monosaccharides except

glycogen.

The purine ___ always binds with the pyrimidine ___ within both DNA and RNA.

guanine; cytosine

All of the following pertain to the atom Carbon-14 except

has 14 neutrons

Compared to a solution of pH 9, a solution of pH 7:

has more H+ ions.

Polar molecules

have an unequal charge distribution

Which is not true about enzymes?

have high-energy bonds between phosphates

Atoms that gain or lose electrons become charged particles called

ions.

Select the statement that most accurately reflects the process of plant material digestion in humans:

it is a process that is dependent upon enzyme (cellulase) production by gut microbiota.

In a later chapter, you will study the staining of bacteria. In the Gram stain, alcohol is used as a decolorizer. What chemical component of the cell does alcohol affect?

lipid

During protein synthesis, ____ RNA is made to be a copy of a gene from the DNA that will be translated into protein.

messenger

The electrons of an atom are

moving in pathways called orbitals

A student forgot to label a beaker containing a DNA solution and a beaker containing a glucose solution. If chemical analysis was performed to identify the contents of each beaker, which of the following would be found in the beaker of DNA but not in the beaker with glucose?

nitrogen and phosphorus

Purines and pyrimidines are components in the building block units of all

nucleic acids.

Protons and neutrons that make up the atom's central core, which is referred to as its

nucleus

The valence number is the

number of outer most electrons

A reaction where an electron is lost is called

oxidation

Choose the term that is the numerical expression of the hydrogen ion concentration in solution.

pH

Which term or phrase does not belong in this list of characteristics describing acids?

pH 8

Choose the statement that describes what will happen to pH as hydrogen ion concentration increases.

pH will decrease

What type of bonds are formed by dehydration synthesis between adjacent amino acids?

peptide

Which of the following functional groups is mismatched to the organic compound in which it is typically contained?

phosphate - carbohydrates

The correct structure of DNA components can be presented as

phosphate-sugar-base

An amino acid contains all of the following except a/n

phosphate.

An example of an amphipathic molecule found in living cells is

phospholipid.

The lipid group that is the major component of cell membranes is the

phospholipids.

Which of the following would have glycosidic bonds?

polysaccharides

An atom has gained an electron. It has been

reduced

Most biochemical macromolecules are polymers, which are chains of

repeating monomers.

Hydrogen bonds

result form attractive forces between molecules with polar covalent bonds

Covalent bonds

result from sharing electrons

Ionic bonds

result from transferring electrons

A fat is called _____ if all carbons of the fatty acid chain are single-bonded to 2 other carbons and 2 hydrogens.

saturated

The alpha (α) helix is a type of _____ protein structure.

secondary

A solution is composed of one or more substances called _____ that are uniformly dispersed in a dissolving medium called a _____.

solutes; solvent

You are preparing a solution by mixing 10 grams of glucose into distilled water. In this solution distilled water is the:

solvent

All of the following are lipids except

starch.

All of the following are polysaccharides except

sterols in cell membranes.

ATP is best described as

the energy molecule of cells.

The lipid group that serves as energy storage molecules is the

triglycerides.

The important solvent associated with living things is

water.