1 Saltatory conduction check all that apply A causes the AP

1. Saltatory conduction: (check all that apply)

A) causes the AP to jump between nodes

B) requires a myelin sheath

C) is on unmyelinated fibers

D)causes erratic transmission

2. The somatic and autonomic nervous systems differ in all of the following except________. (check all that applies)

A) the molecules used in their action potentials

B) having muscariinic cholinergic receptors

C)the placement of their ganglia

3. If a cell is placed into an unknown solution and it shrinks, what can be concluded about the unknown solution? (check all that apply)

A) intracellular fluid is isotonic to extracellular fluid

B) intracellular fluid is hypertonic to extracellular fluid

C) intracellular fluid is hypotonic to extracellular fluid

D)extracellular fluid is hypoosmotic to intracellular

4. Each amino acid differs from others in all but: (check all that apply)

A) containing a carboxyl group

B) number of central carbon atoms

C) chemical structure of the R group

D)size of the amino group

5. Entering a competition where you drink as much water as you can without urinating: (check all that apply)

A) could kill you by bursting your cell membranes

B) is less likely to occur if you drink an electrolyte drink rather than pure water

C) may result in extracellular fluid being hypotonic to intracellular fluid

D)cannot harm you, we are walking bags of water and you are just superhydrating

6. The rate of diffusion in a human body: (check all that apply)

A) decreases with decreasing distance

B) increases with decreased surface area

C) increases with increased molecular weight

D) increases with increased concentration gradient

E)increases with increased permeability of the membrane

7. Gated channels for sodium ions may include osmotic gates, which respond to barometric pressure.

A) True

B) False

8. You may actively transport water across a membrane.

A) True

B) False

9. Which of the following are chemically digested by the stomach: (check all that apply)

A) Protein

B) Fats

C) Carbohydrates

10. The ingestion of a meal high in fat content would cause which of the following to occur? (check all that apply)

A) the pancreas would increase its release of lipase

B) bile would be added to the stomach to aid in digestion

C) you will digest it better if you chew and mix it well with salivary lipase

D) sphincter of Oddi would relax and release bile produced by the gallbladder

11. Internal respiration includes each of the following except: (check all that apply)

A) Kreb\'s cycle

B) transport in the blood

C) cellular respiration

D) chemiosmosis

12. When discussing a premature baby who does not have compliant lungs, what does that include: (check all that apply)

A) decreased total lung capacity

B) decreased surface area and therefore decreased rate of exchange

C) a less steep slope of the exhalation between IRV and a passive exhale

D) need to use a parasympathetic antagonist or sympathetic agonist as therapy

13. Which of the following is not a method by which antibodies work? (check all that apply)

A) neutralizing a toxin by changing its structure

B) agglutinization

C)phagocytosis of the foreign matter

14. Inflammation involves: (choose all that apply)

A) increased rates of diapedesis

B) vasodilation

C) increased edema

D) pain due to increased pressure on the Pacinian corpuscles

15. Learning: (check all that apply)

A) uses Papez\'s circuit for problem solving

B) ceases to occur in the occipital lobe of a blind person

C) is an active verb (no one can be forced to learn, it requires effort, \"a workout for your brain\")

D) involves the limbic system

Solution

1). A) causes the AP to jump between nodes -----> TRUE

B) requires a myelin sheath --------> TRUE

C) is on unmyelinated fibers -----> FALSE

D) causes erratic transmission -------> FALSE (saltatory conduction allows the impulse to move in one direction)

The gap junctions found at regular intervals in the myelin sheath are called as Nodes of Ranveir.   Myelin sheath does not allow the exchange of ions through it and exchange of ions occurs at Nodes of Ranveir only. Myelin sheath helps in the faster conduction of impulses through the axons by saltatory conduction (impulses jump from one node to another).

Thus, the impulses are conducted faster in myelinated neurons (glial cells insulate the neurons with myelin sheath) than non-myelinated neurons. In non myelinated neurons, the ions move through the axon length, so the conduction is slower.