Lecture Exam 1

A  Paracrine

B  muscle cell

C  collagen cells

D  epithelial cells

A  TRUE

B  FALSE

A  An increase in the effects of heroin

B  The same effects from heroin plus additional effects of naloxone

C  A decrease in the effects of heroin

D  A new set of effects unlike those of heroin alone

A  FALSE

B  TRUE

A  It splits and activates G-protein subunits.

B  It is the first messenger that binds to the integral membrane protein receptor.

C  Along with diacylglycerol, it activates protein kinase C.

D  It phosphorylates cell proteins.

E  It binds to the endoplasmic reticulum and causes therelease ofinositol trisphosphate

A  Cyclic AMP

B  Glucose

C  Protein kinase

D  Thyroid hormone

E  Sodium

A  When the extracellular concentration of a chemical messenger reaches a very high level, it overwhelms transporter molecules and the chemical floods into the cell.

B  Some cellular receptors have such low affinity for chemical ligands that it can require a million or more molecules to activate them.

C  Only hydrophilic first-messenger molecules can activate second-messenger molecules within the cell cytosol.

D  A single first-messenger molecule activates multiple second-messenger molecules, each of which activate thousands of enzymes.

A  FALSE

B  TRUE

A  Increasing the expression of Camp

B  Increasing the availability of phosphodiesterase molecules

C  Decreasing the activity of cAMP-dependent protein kinase

D  Acting as an agonist on the receptor for epinephrine, a hormone that increases heart contractility

E  Inhibiting phosphodiesterase activity

A  Cyclic AMP-dependent protein kinase activates two kinds of enzymes.

B  The activated receptor complex stimulates production of two different second messengers.

C  Epinephrine is binding to two types of receptors in the plasma membrane.

D  Cyclic AMP directly activates enzymes that catabolize glycogen and fat.

A  There are two types of receptors for epinephrine that use the same second-messenger system.

B  There are two types of epinephrine receptors with different affinities for epinephrine that use two different second-messenger systems.

C  There is one type of epinephrine receptor that uses two second-messenger systems.

D  At higher concentrations epinephrine can pass through the plasma membrane and directly stimulate contraction within the cell.

A  TRUE

B  FALSE

A  TRUE

B  FALSE

A  FALSE

B  TRUE

A  Water

B  Solutes

C  Glucose

D  Lipid molecules

E  Charged particles

A  FALSE

B  TRUE

A  Substance X and Substance Y will diffuse at the same rate, as they are of equal size and concentration.

B  Substance Y will diffuse faster.

C  Substance X will diffuse faster.

A  TRUE

B  FALSE

A  TRUE

B  FALSE

A  Hypoosmotic solutions are always hypotonic

B  The term “tonicity” refers to the effect that a solution has on the degree of stretch or shrinking of the cell membrane.

C  The term “osmolarity” refers to the osmotic properties of a solution, regardless of its tonicity.

D  Hypertonic solutions are always hyperosmotic.

E  Isotonic solutions are always isoosmotic.

A  FALSE

B  TRUE

A  Facilitated diffusion of glucose to the bloodstream from the lumen

B  Tightening the tight junctions between epithelial cells

C  Opening of aquaporins on the apical membrane

D  Active transport of Na + from the lumen to the basolateral side

E  Active transport of H + from the basolateral side to the lumen

A  can be carbohydrate molecules.

B  are catalysts in chemical reactions.

C  are broken down during chemical reactions they catalyze.

D  are polymers of ATP that store large amounts of energy.

E  have names generally ending in the suffix “-ose.”

A  phospholipids and proteins.

B  cytosol.

C  water.

D  proteins and glycocalyx.

E  phospholipids and nucleic acids.

A  They perform the opposite function as phosphatases.

B  They produce effects similar to allosteric modulation.

C  They remove phosphate groups from proteins.

D  They use ATP to carry out their reactions.

E  They add phosphate groups to proteins.

A  TRUE

B  FALSE

A  When present, it increases the binding of a ligand to its receptor.

B  It decreases the amount of ligand required to activate the protein.

C  It binds to a different binding site on the protein, altering the protein shape so that a ligand cannot bind.

D  It blocks the binding of the ligand to its binding site and prevents activation of the protein.

A  FALSE

B  TRUE

A  FALSE

B  TRUE

A  2 molecules of NADH and 2 molecules of water

B  2 molecules of ATP, 2 molecules of water, and 2 molecules of lactate

C  2 molecules of pyruvate, 2 molecules of lactate, and 2 ATP

D  2 molecules of pyruvate and 36 molecules of ATP

E  2 molecules of pyruvate, 2 molecules of water, and 2 NADH

A  TRUE

B  FALSE

A  Cholesterol will migrate away from phospholipids and toward proteins.

B  Cholesterol will associate with adjacent phospholipid molecules and stay near them.

C  All of the molecules will move freely in the lipid bilayer.

D  Cholesterol will be excluded from the bilayer and will no longer be associated with phospholipids because they have different properties.

A  Results in molecules with an even number of carbon atoms only

B  Begins with a molecule of acetyl coenzyme A

C  The enzymes that catalyze it are in the same location as those that mediate fatty acid catabolism

D  Takes place in the cytosol of cells

E  Requires more energy than is produced by the catabolism of the same fatty acid

A  TRUE

B  FALSE

A  TRUE

B  FALSE

A  TRUE

B  FALSE

A  TRUE

B  FALSE

A  No effect on blood glucose level

B  Decrease blood glucose level

C  Increase blood glucose level

A  Ionic bonds

B  Hydrophobic interactions

C  Hydrogen bonds

D  Disulfide bridges

E  You are likely to find all of these within a single protein.

A  FALSE

B  TRUE

A  bipolar.

B  amphipathic.

C  hydrophobic.

D  unipolar.

E  hydrophilic.

A  The number of neutrons

B  The number of electrons

C  The number of protons

D  The ratio of protons to electrons

E  The number of bonds it can form

A  Ionic bonds

B  Covalent bonds between two cysteine amino acids

C  Van der Waals forces

D  Covalent bonds between purine and pyrimidine bases

E  Hydrogen bonds

A  FALSE

B  TRUE

A  TRUE

B  FALSE

A  They repeat approximately every 24 hours, like daily spikes in hormone secretion.

B  They are voluntary rhythms, like the time you decide to eat lunch each day.

C  They cease to occur when a person is in a dark environment.

D  They cease to occur when a person is in a dark environment.

E  They are cyclical, like the 28-day female menstrual cycle.

A  TRUE

B  FALSE

A  After eating a large batch of salty popcorn, levels of salt in the urine increase.

B  A person who becomes very nervous begins to sweat profusely.

C  As age increases, the amount of calcium in bones tends to decrease.

D  Increasing the size of fast-food restaurant portions causes body weight to increase.

E  After going outside on a hot day, the core body temperature increases.

A  TRUE

B  FALSE

A  Evolution

B  Physiological acclimatization

C  Developmental acclimatization

D  Feedforward regulation

E  Positive feedback

A  FALSE

B  TRUE

A  Receptor, afferent pathway, integrating center, efferent pathway, effector

B  Effector, efferent pathway, integrating center, afferent pathway, receptor

C  Integrating center, receptor, afferent pathway, efferent pathway, effector

D  Receptor, efferent pathway, integrating center, afferent pathway, effector

E  Effector, afferent pathway, integrating center, efferent pathway, receptor