« previous next »

Author Question: The component of the conduction system referred to as the pacemaker of the heart is the: a. ... (Read 130 times)

chads108

  • Hero Member
  • *****
  • Posts: 507
on: Jun 25, 2018
The component of the conduction system referred to as the pacemaker of the heart is the:
 
  a. Atrioventricular (AV) node.
  b. Sinoatrial (SA) node.
  c. Bundle of His.
  d. Bundle branches.

Question 2

When assessing a newborn infant who is 5 minutes old, the nurse knows which of these statements to be true?
 
  a. The left ventricle is larger and weighs more than the right ventricle.
  b. The circulation of a newborn is identical to that of an adult.
  c. Blood can flow into the left side of the heart through an opening in the atrial septum.
  d. The foramen ovale closes just minutes before birth, and the ductus arteriosus closes immediately after.


macybarnes

  • Sr. Member
  • ****
  • Posts: 312
Reply #1 on: Jun 25, 2018
Answer to Question 1

ANS: B
Specialized cells in the SA node near the superior vena cava initiate an electrical impulse. Because the SA node has an intrinsic rhythm, it is called the pacemaker of the heart.

Answer to Question 2

ANS: C
First, approximately two thirds of the blood is shunted through an opening in the atrial septum, the foramen ovale, into the left side of the heart, where it is pumped out through the aorta. The foramen ovale closes within the first hour after birth because the pressure in the right side of the heart is now lower than in the left side.


Related Topics

Need homework help now?

Ask unlimited questions for free

Ask a Question
« previous next »
 

Did you know?

Parkinson's disease is both chronic and progressive. This means that it persists over a long period of time and that its symptoms grow worse over time.

Did you know?

Dogs have been used in studies to detect various cancers in human subjects. They have been trained to sniff breath samples from humans that were collected by having them breathe into special tubes. These people included 55 lung cancer patients, 31 breast cancer patients, and 83 cancer-free patients. The dogs detected 54 of the 55 lung cancer patients as having cancer, detected 28 of the 31 breast cancer patients, and gave only three false-positive results (detecting cancer in people who didn't have it).

Did you know?

Bacteria have been found alive in a lake buried one half mile under ice in Antarctica.

Did you know?

The use of salicylates dates back 2,500 years to Hippocrates’s recommendation of willow bark (from which a salicylate is derived) as an aid to the pains of childbirth. However, overdosage of salicylates can harm body fluids, electrolytes, the CNS, the GI tract, the ears, the lungs, the blood, the liver, and the kidneys and cause coma or death.

Did you know?

Coca-Cola originally used coca leaves and caffeine from the African kola nut. It was advertised as a therapeutic agent and "pickerupper." Eventually, its formulation was changed, and the coca leaves were removed because of the effects of regulation on cocaine-related products.

The vertebrate vestibular system. The vertebrate vestibular system.
Sagittal section of upper respiratory system illustrating the internal anatomy of the nasal cavity, Sagittal section of upper respiratory system illustrating the internal anatomy of the nasal cavity,
Blood Flow Through the Cardiorespiratory System Blood Flow Through the Cardiorespiratory System
Procedures and Diagnostic Tests Related to the Integumentary System Procedures and Diagnostic Tests Related to the Integumentary System
The heart: (a) coronary arteries and veins The heart: (a) coronary arteries and veins
Cardiac conduction system Cardiac conduction system
Video: Reflex arc construction

For a complete list of videos, visit our video library