Human Biology - Exam 6

Chloride ions passively follow sodium that has been actively transported out of tubular cells, due to the attraction of negatively charged ions to positively charged ions.

True

Osmotic concentration in the descending limb of the loop of Henle increases as water moves out.

True

Reestablishment of the resting potential in a neuron following an action potential requires the activity of the sodium-potassium pump.

True

When you are taking an exam, the sympathetic nervous system is dominant.

True

Using the figure below, identify the structure that represents the eye lens.

U

Movement of sodium across the cells of the collecting duct relies on which one of the following?

active transport

Bacterial and viral infections of the brain are rare because the ________ prevents most viruses, proteins, and bacteria from entering the cerebrospinal fluid.

blood-brain barrier

People who are intoxicated cannot coordinate their movements or walk a straight line because alcohol disrupts the normal function of which region of the brain?

cerebellum

The region of brain that coordinates antagonistic muscle movements is the:

cerebellum

LASIK treatment functions to improve eyesight by:

changing the shape of the cornea.

The hairpin design of the loop of Henle allows events on one side of the loop to influence the events on the other side, by a process referred to as:

countercurrent exchange.

Convergence occurs when several presynaptic cells:

form a synapse with a single postsynaptic cell.

Receptors for fast pain:

generally occur in or near skin.

A stronger stimulus results in which one of the following?

greater frequency of action potentials

What type of neuron transmits impulses within the central nervous system?

interneuron

A student noticed that when he closed his eyes, he could still determine the position of his arms and legs. This is largely due to the activity of:

mechanoreceptors

Control of respiratory rate, heart rate, and blood pressure is integrated through the:

medulla oblongata.

Which component of the nervous system is divided into the somatic and autonomic divisions?

motor

Only 20% of cells in the human nervous system are neurons, and the rest are cells that support and protect neurons called ________ cells.

neuroglial

Arrival of an action potential at an axon terminal ultimately results in the release of ________ into the synaptic cleft.

neurotransmitters

Cranial nerves and spinal nerves are part of the ________ nervous system.

peripheral

The primary sources of the nitrogenous wastes that are eliminated by the kidneys are:

proteins

Over 99% of the water filtered through the glomerulus is reabsorbed. At which one of the following locations does most of this water reabsorption (65 - 70%) occur?

proximal tubule

Some sensory receptors stop sending action potentials even though the original stimulus persists. This is known as which one of the following?

receptor adaptation

Which of the following receive(s) a physical or chemical stimulus and ultimately cause(s) nerve impulses to be generated in sensory neurons?

receptors

Excitatory neurotransmitters encourage the generation of new electrical impulses by which one of the following?

stimulating depolarization of postsynaptic neurons

Its effect is to prepare the body for emergencies:

sympathetic nervous system

Which part of the brain functions like a switchboard for the brain?

thalamus

For an action potential to be generated, a minimum membrane voltage, or a(n) ________, must be reached.

threshold

Texting while driving involves which types of driving distractions?

visual, cognitive, and manual

Consider a red blood cell traveling in the renal artery. It passes through several different functional vessels before entering the renal vein. Consider the vessels listed below. Which one of the following answers lists the CORRECT order in which the red blood cell passes through these vessels? 1. peritubular capillaries 2. efferent arteriole 3. afferent arteriole 4. glomerulus 5. renal vein

3, 4, 2, 1, 5

Alcohol has diuretic effects, increasing urine output. By which one of the following is this mediated?

Alcohol inhibits the release of ADH.

Aldosterone is secreted:

Contribute to maintenance of salt balance

An action potential is a long or rapid release of energy, generated by the sodium-potassium pumps of neurons.

False

The figure below is a diagram of an eye with an abnormality that would result in vision problems. A person with this condition would be considered farsighted and would require convex lenses in order to see objects in the distance.

False

The repolarization phase of an action potential is dependent on the sodium-potassium pump.

False

Which part of the central nervous system is associated with emotions?

Limbic system

When repolarization is occurring during an action potential, ________ channels are closed.

Na+ (sodium)