Guyton's Human Physiology: Digestive System and Muscle Function Quiz

1. What is the correct order of layers in the intestinal wall from outer to inward?

1.Serosa, 2.Mucosa, 3.Circular muscle layer, 4.Submucosa, 5.Longitudinal muscle layer

1.Mucosa, 2.Circular muscle layer, 3.Serosa, 4.Submucosa, 5.Longitudinal muscle layer

1.Mucosa, 2.Submucosa, 3.Circular muscle layer, 4.Longitudinal muscle layer, 5.Serosa

From outer to inward:1.Serosa2.Longitudinal muscle layer3.Circular muscle layer4.Submucosa5.Mucosa

The correct order of layers in the intestinal wall from outer to inward is: 1.Serosa, 2.Longitudinal muscle layer, 3.Circular muscle layer, 4.Submucosa, 5.Mucosa. This arrangement provides structural support and functional roles in the digestive process.

Explanation

The correct order of layers in the intestinal wall from outer to inward is: 1.Serosa, 2.Longitudinal muscle layer, 3.Circular muscle layer, 4.Submucosa, 5.Mucosa. This arrangement provides structural support and functional roles in the digestive process.

2. What type of junction connects smooth muscle fibers?

Tight junction

Hemidesmosome

Desmosome

Gap junction

Smooth muscle fibers are connected by gap junctions, which allow for the direct passage of ions and small molecules between cells, aiding in synchronized muscle contractions.

Explanation

Smooth muscle fibers are connected by gap junctions, which allow for the direct passage of ions and small molecules between cells, aiding in synchronized muscle contractions.

3. Which cells serve as the electrical pacemaker for smooth muscle cells?

Interstitial cells of cajal (?????? :)

Red blood cells

Neurons

Epithelial cells

Smooth muscle cells rely on interstitial cells of cajal (ICC) to generate electrical pacemaker activity, not neurons, red blood cells, or epithelial cells.

Explanation

Smooth muscle cells rely on interstitial cells of cajal (ICC) to generate electrical pacemaker activity, not neurons, red blood cells, or epithelial cells.

4. Nerve Fiber ?? ????????, sodium channel ?? ??? ???? Na+ , Fiber ?? ????? ????? action potential ??? ?????? GIT smooth muscle fiber ?? ???????? sodium channel ?? ??? ???? ?????? ??????? ?? ??????? action potential ??? ???? ?????? .

Iron-magnesium channel

Carbon-hydrogen channel

Potassium-chloride channel

Calcium-sodium channel

The question is referring to the specialized ion channel responsible for the conduction of action potentials in nerve fibers and smooth muscle fibers. The correct answer, calcium-sodium channel, allows for the flow of calcium and sodium ions during the depolarization phase of generating action potentials.

Explanation

The question is referring to the specialized ion channel responsible for the conduction of action potentials in nerve fibers and smooth muscle fibers. The correct answer, calcium-sodium channel, allows for the flow of calcium and sodium ions during the depolarization phase of generating action potentials.

5. What is the role of calcium-sodium channel in GIT smooth muscle fiber?

Controls heart rate.

Synthesizes neurotransmitters in the brain.

Regulates oxygen levels in the blood.

GIT smooth muscle fiber ?? ???? ?????? Ca+ ? ???? Na+ ???????

The calcium-sodium channel allows for the movement of calcium and sodium ions within GIT smooth muscle fiber, aiding in muscle contraction and relaxation.

Explanation

The calcium-sodium channel allows for the movement of calcium and sodium ions within GIT smooth muscle fiber, aiding in muscle contraction and relaxation.

6. What channel is responsible for generating action potential in the GIT smooth muscle fiber?

The K channel is responsible for generating action potential in the GIT smooth muscle fiber.

The Na-Cl channel is responsible for generating action potential in the GIT smooth muscle fiber.

The Ca-K channel is responsible for generating action potential in the GIT smooth muscle fiber.

???? Ca-Na channel ????? ??????? ????? ? ???? ??? ???? ??? ????

The Ca-Na channel allows the influx of calcium and sodium ions, leading to depolarization and action potential generation in the smooth muscle fiber of GIT. The other incorrect answers do not accurately represent the channel responsible for this action.

Explanation

The Ca-Na channel allows the influx of calcium and sodium ions, leading to depolarization and action potential generation in the smooth muscle fiber of GIT. The other incorrect answers do not accurately represent the channel responsible for this action.

7. What type of electrical wave is associated with GIT smooth muscle?

5. erratic wave

4. steady wave

1.slow wave2.spikes

3. fast wave

In the gastrointestinal tract (GIT) smooth muscle, the electrical activity is characterized by slow waves and spikes. Slow waves are the pacemaker activity while spikes are action potentials that contribute to muscle contractions.

Explanation

In the gastrointestinal tract (GIT) smooth muscle, the electrical activity is characterized by slow waves and spikes. Slow waves are the pacemaker activity while spikes are action potentials that contribute to muscle contractions.

8. What is the relationship between slow wave and muscle contraction in terms of spikes?

Fast wave patterns trigger muscle contractions through the release of Ca+ ions.

Slow wave patterns have no effect on muscle contractions without spike potential.

Irregular spikes in slow wave patterns inhibit muscle contractions.

The correct answer explains how slow wave patterns in muscle contractions are related to spikes and the influence of Ca+ and Na+ ions. The incorrect answers provide common misconceptions or false statements about the relationship between slow waves, muscle contractions, and spikes.

Explanation

The correct answer explains how slow wave patterns in muscle contractions are related to spikes and the influence of Ca+ and Na+ ions. The incorrect answers provide common misconceptions or false statements about the relationship between slow waves, muscle contractions, and spikes.

9. What are the two plexuses of the enteric nervous system?

3. vagal plexus

4. spinal cord plexus

5. brachial plexus

1.my-enteic plexus/ Auer-bach's plexus2.submucosal plexus or Meiss-ner's plexus

The correct answers are 1 and 2 because the enteric nervous system consists of two main plexuses: myenteric plexus (also known as Auerbach's plexus) and submucosal plexus (also known as Meissner's plexus). The other options are incorrect as they do not pertain to the enteric nervous system.

Explanation

The correct answers are 1 and 2 because the enteric nervous system consists of two main plexuses: myenteric plexus (also known as Auerbach's plexus) and submucosal plexus (also known as Meissner's plexus). The other options are incorrect as they do not pertain to the enteric nervous system.