Lecture Exam 1

A  muscle cell

B  collagen cells

C  Paracrine

D  epithelial cells

A  TRUE

B  FALSE

A  A new set of effects unlike those of heroin alone

B  A decrease in the effects of heroin

C  The same effects from heroin plus additional effects of naloxone

D  An increase in the effects of heroin

A  FALSE

B  TRUE

A  It phosphorylates cell proteins.

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

C  It splits and activates G-protein subunits.

D  Along with diacylglycerol, it activates protein kinase C.

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

A  Sodium

B  Thyroid hormone

C  Glucose

D  Cyclic AMP

E  Protein kinase

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

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

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

A  FALSE

B  TRUE

A  Decreasing the activity of cAMP-dependent protein kinase

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

C  Increasing the expression of Camp

D  Increasing the availability of phosphodiesterase molecules

E  Inhibiting phosphodiesterase activity

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

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

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

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

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

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

A  FALSE

B  TRUE

A  TRUE

B  FALSE

A  FALSE

B  TRUE

A  Water

B  Lipid molecules

C  Charged particles

D  Glucose

E  Solutes

A  TRUE

B  FALSE

A  Substance X will diffuse faster.

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

C  Substance Y will diffuse faster.

A  TRUE

B  FALSE

A  TRUE

B  FALSE

A  Hypertonic solutions are always hyperosmotic.

B  Hypoosmotic solutions are always hypotonic

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

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

E  Isotonic solutions are always isoosmotic.

A  FALSE

B  TRUE

A  Opening of aquaporins on the apical membrane

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

C  Tightening the tight junctions between epithelial cells

D  Facilitated diffusion of glucose to the bloodstream from the lumen

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

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

B  are catalysts in chemical reactions.

C  are broken down during chemical reactions they catalyze.

D  can be carbohydrate molecules.

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

A  proteins and glycocalyx.

B  water.

C  phospholipids and proteins.

D  cytosol.

E  phospholipids and nucleic acids.

A  They add phosphate groups to proteins.

B  They perform the opposite function as phosphatases.

C  They produce effects similar to allosteric modulation.

D  They use ATP to carry out their reactions.

E  They remove phosphate groups from 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 blocks the binding of the ligand to its binding site and prevents activation of the protein.

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

A  FALSE

B  TRUE

A  FALSE

B  TRUE

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

B  2 molecules of NADH and 2 molecules of water

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

D  2 molecules of pyruvate and 36 molecules of ATP

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

A  FALSE

B  TRUE

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

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

C  Cholesterol will migrate away from phospholipids and toward proteins.

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

A  Begins with a molecule of acetyl coenzyme A

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

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

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

E  Takes place in the cytosol of cells

A  FALSE

B  TRUE

A  TRUE

B  FALSE

A  FALSE

B  TRUE

A  FALSE

B  TRUE

A  Increase blood glucose level

B  Decrease blood glucose level

C  No effect on blood glucose level

A  Ionic bonds

B  Hydrophobic interactions

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

D  Hydrogen bonds

E  Disulfide bridges

A  FALSE

B  TRUE

A  unipolar.

B  bipolar.

C  amphipathic.

D  hydrophobic.

E  hydrophilic.

A  The number of electrons

B  The number of neutrons

C  The number of bonds it can form

D  The number of protons

E  The ratio of protons to electrons

A  Hydrogen bonds

B  Covalent bonds between purine and pyrimidine bases

C  Covalent bonds between two cysteine amino acids

D  Ionic bonds

E  Van der Waals forces

A  FALSE

B  TRUE

A  TRUE

B  FALSE

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

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

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

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

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

A  FALSE

B  TRUE

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

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

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

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

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

A  FALSE

B  TRUE

A  Positive feedback

B  Feedforward regulation

C  Developmental acclimatization

D  Physiological acclimatization

E  Evolution

A  FALSE

B  TRUE

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

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

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

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

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