Biology Quiz-4

While shopping at your local drugstore, you stop at the blood pressure machine. It measures your blood pressure as 115/75 (good— that's healthy!). This number means that

• arterial pressure is 115 mm Hg when the ventricles contract and 75 mm Hg in between ventricular

• your sinoatrial node generates a 115 mV signal and your atrioventricular node generates a 75 mV signal

• arterial pressure is 115 mm Hg when the atria contract and 75 mm Hg in between atrial contractions

• arterial pressure is 75 mm Hg when the ventricles contract and 115 mm Hg in between ventricular contractions

The 'QRS' complex visible in a normal electrocardiogram is associated with the

• excitation from the AV node and repolarization of the atria

• excitation from the SA node and repolarization of the ventricles

• excitation from the SA node and depolarization of the atria

• excitation from the AV node and depolarization of the ventricles

Which of the following statements about the structure of the fish gill is false?

• Exchange of respiratory gases occurs within the lamellae of the gill filaments.

• Afferent vessels bring blood to the gills, whereas efferent vessels take blood away from the gills

• The lamellae greatly increase the surface area for gas exchange

• The efferent and afferent vessels are the countercurrent flow system of the gill

Which of the following characterizes the lungs of mammals?

• countercurrent air flow

• reciprocal ventilation

• tidal ventilation

• crosscurrent air flow

Which organ is not part of the gastrointestinal tract?

• Gallbladder

• large intestine

• Esophagus

• mouth

As compared to the circulatory system of most fishes, the circulatory system of adult amphibians has the advantage of

• a partial separation between pulmonary and systemic circulation

• heart metamorphosis

• a four-chambered heart

• separation between oxygenated and deoxygenated blood

Which of the following represents the correct order in which action potentials spread from the atria to the ventricles during a normal heartbeat in the mammalian heart?

• Atrioventricular node, AV bundle , Purkinje fibers

• Purkinje fibers, AV bundle, atrioventricular node

• Atrioventricular node, Purkinje fibers, AV bundle

• Sinoatrial node, Purkinje fibers, AV bundle

Peristalsis

• Is under voluntary control

• Is a wave of muscular contraction

• Involves back-and-forth movement for mixing

• All choices are true

Gas exchange in birds occurs in the

• Parabronchi

• anterior air sac

• Postbronchi

• posterior air sac

Late one night, while studying for your anatomy class, you open a box of saltine crackers to do a little snacking. After chewing on a starchy morsel for a few minutes, you begin to notice a sweet taste in your mouth. What accounts for this?

• Esophageal reflux

• Salivary amylase activity

• Phagocytosis by the pharyngeal tonsils produces by-products that taste sweet

• Activity of bacteria in the mouth lowers the pH