Quiz 1

A placebo is A) a drug or treatment that is expected to have no pharmacological effect. B) a hole in a cavity wall through which an organ protrudes. C) any drug in a class of drugs commonly used as pain relievers. D) a nutritive and respiratory organ in fetal development. E) any drug being tested in a clinical trial.

A)

All of the following are types of mediated transport except one. Identify the exception. A) simple diffusion B) primary active transport C) facilitated diffusion D) secondary active transport

A)

An enzyme that transfers phosphates from ATP to a substrate molecule is a A) kinase. B) transferase. C) hydrolase. D) ligase. E) lipase.

A)

An integrating center A) evaluates incoming signals and compares it with the setpoint. B) is an electrical and/or chemical signal that travels to the effector. C) is the minimum stimulus that must be achieved to set the reflect response in motion. D) is the disturbance or change that sets the pathway in motion.

A)

Enzymes increase reaction rate by A) lowering the activation energy of a reaction. B) converting an endergonic reaction to an exergonic reaction. C) None of these choices are correct. D) increasing the free energy in the products. E) raising the activation energy of a reaction.

A)

Pinocytosis is a type of A) endocytosis. B) endocytosis and exocytosis. C) phagocytosis. D) exocytosis and phagocytosis. E) exocytosis.

A)

During the synthesis of proteins, amino acids are assembled in the proper sequence because the tRNA molecules that bring them to the ribosome have a(n) _______________ that is complementary to a specific codon in the mRNA.

Anti-codon

Cholesterol is A) a structural component of cell membranes. B) a precursor to steroid hormones and a structural component of cell membranes C) a dangerous fat that is absent from a healthy body. D) a precursor to steroid hormones.

B)

Saturation occurs when A) a carrier molecule has the ability to transport only one molecule or a group of closely related molecules. B) a group of carrier proteins is operating at its maximum rate. C) molecules are moved by the use of vesicles. D) a preference of a carrier protein for a substance is demonstrated based on the differing affinities of the carrier for the substrates. E) the energy required to move molecules results from a high-energy bond.

B)

What are the two extracellular fluid compartments in the body? A) intracellular and plasma B) plasma and the fluid portion of the blood C) plasma and interstitial D) None of the answers are correct. E) interstitial and intracellular

B)

When an enzyme's activity is destroyed by heat or a change in pH, the enzyme is said to be A) broken. B) denatured. C) conjugated. D) toxic. E) tertiary.

B)

Which type of tissue below has minimal extracellular matrix? A) neural only B) epithelial, neural, and muscle C) muscle only D) epithelial only E) connective only

B)

Which of the following elements form polar covalent bonds? A) sodium and chlorine B) hydrogen and oxygen C) carbon and hydrogen D) carbon and carbon E) hydrogen and hydrogen

B) Hydrogen and oxygen

Fick's law of diffusion states that the rate of diffusion across a membrane is A) All of these answers are correct. B) proportional to membrane permeability, but inversely proportional to concentration gradient and surface area. C) proportional to concentration gradient, surface area, and membrane permeability. D) proportional to surface area and membrane thickness, but inversely proportional to concentration gradient. E) proportional to membrane thickness and surface area

C)

If a substance has a pH that is less than 7, it is considered A) neutral. B) a buffer. C) acidic. D) a salt. E) alkaline.

C)

The most important energy-transferring compound in cells is a nucleotide known as A) protein. B) fructose. C) adenosine triphosphate. D) glucose. E) deoxyribonucleic acid.

C)

Which of the following are considered differences between endocrine and neural control systems? A) duration of action B) nature of the signal C) All of the answers are correct. D) speed E) specificity

C)

You conduct an experiment on twenty 18-year-old male subjects to see how various intensities of exercise influence heart rate. Which of the following is/are considered a dependent variable? A) More than one of the answers is correct. B) sex of subjects C) heart rate D) age of subjects E) intensity of exercise

C)

Atoms in a covalent molecule A) share electrons singly, never in pairs. B) share electrons in triple pairs. C) share electrons in single pairs. D) can share electrons in single pairs, double pairs, or triple pairs. E) share electrons in double pairs.

D)

Nucleic acids are polymers of units called A) ribose. B) bases. C) amino acids. D) nucleotides. E) fatty acids.

D)

An ion widely important in intracellular signaling is A) chloride. B) potassium. C) cobalt. D) sodium. E) calcium.

E)

The means by which a cell transports large molecules out of the cell is called

Exocytosis

RNA is usually ________-stranded.

Single

mRNA is created in a process called __________________. It then leaves the ______ and enters the cytosol to direct ____________, the assembly of amino acids into protein.

Transcription, nucleus, translation

Amino acids are carried to the ribosomes to be incorporated into polypeptide chains by

tRNA

Essential amino acids that are used to build proteins A) exist in twenty six different configurations. B) can be used medically for both diagnosis and treatment of diseases. C) can only be made by cells within our bodies. D) are linked together by ionic chemical bonds in proteins. E) can be derived from the foods we eat and digest.

E)