L18 Heart Rate Regulation
24 Questions
0 Views

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to Lesson

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

Which part of the nervous system is primarily responsible for regulating heart rate under resting conditions?

  • Posterior hypothalamus
  • Cerebral cortex
  • Respiratory center
  • Vagal tone (correct)

Which of the following reflexes is responsible for the increase in heart rate due to increased venous return?

  • Carotid sinus syndrome
  • Bainbridge reflex (correct)
  • McDowal's reflex
  • Marey's Law

According to Marey's Law, what is the relationship between heart rate and arterial blood pressure?

  • Heart rate is exponentially related to arterial blood pressure
  • Heart rate is independent of arterial blood pressure
  • Heart rate is directly proportional to arterial blood pressure
  • Heart rate is inversely proportional to arterial blood pressure (correct)

Which of the following is the correct pathway for the Bainbridge reflex?

<p>Increased venous return → increased right atrial pressure → stimulation of atrial stretch receptors → increased cardiac filling → increased heart rate (B)</p> Signup and view all the answers

Which part of the hypothalamus is responsible for stimulating the Cardiac Acceleratory Center (CAC) and increasing heart rate?

<p>Posterior hypothalamus (A)</p> Signup and view all the answers

What is the effect of deep inspiration on heart rate according to the text?

<p>Deep inspiration increases heart rate (B)</p> Signup and view all the answers

What is the mechanism by which stimulation of the carotid sinus baroreceptors can lead to bradycardia?

<p>Stimulation of the Cardiac Inhibitory Center (CIC) (D)</p> Signup and view all the answers

Which of the following is a direct mechanism by which the respiratory center can influence heart rate?

<p>Respiratory sinus arrhythmia (C)</p> Signup and view all the answers

What is the effect of sympathetic stimulation on the heart?

<p>Increases the heart rate (C)</p> Signup and view all the answers

Which of the following statements about heart rate is true?

<p>The average heart rate for adults is around 70 beats per minute (B)</p> Signup and view all the answers

Which factor does NOT contribute to physiological variations in heart rate?

<p>Body mass index (BMI) (B)</p> Signup and view all the answers

Which of the following statements about the regulation of heart rate is true?

<p>The parasympathetic nervous system decreases the SA nodal discharge and heart rate (D)</p> Signup and view all the answers

Which of the following heart rates would be considered bradycardia?

<p>50 beats per minute (C)</p> Signup and view all the answers

What is the typical heart rate for an infant?

<p>Around 120 beats per minute (C)</p> Signup and view all the answers

Which of the following factors contributes to a lower heart rate in athletes?

<p>Their heart is stronger and more efficient (A)</p> Signup and view all the answers

What is the primary mechanism by which the autonomic nervous system regulates heart rate?

<p>By controlling the SA nodal discharge (C)</p> Signup and view all the answers

What is the effect of voluntary contraction of skeletal muscles on heart rate?

<p>Tachycardia (A)</p> Signup and view all the answers

Which of the following accurately describes the effect of hypoxia (low oxygen) on heart rate?

<p>Mild to moderate hypoxia causes tachycardia, while severe hypoxia causes bradycardia (C)</p> Signup and view all the answers

Which hormone is associated with an increase in heart rate?

<p>All of the above (D)</p> Signup and view all the answers

What is the effect of applying pressure on the eyeball (oculo-cardiac reflex) on heart rate?

<p>Bradycardia (D)</p> Signup and view all the answers

How does moderate hypercapnia (increased carbon dioxide) affect heart rate?

<p>Causes tachycardia (C)</p> Signup and view all the answers

Which of the following substances causes bradycardia (decreased heart rate)?

<p>Morphine (B)</p> Signup and view all the answers

What is the approximate increase in heart rate for every 1°C rise in body temperature?

<p>10-13 beats per minute (A)</p> Signup and view all the answers

Which of the following is NOT a factor that regulates heart rate?

<p>Dietary habits (B)</p> Signup and view all the answers
Use Quizgecko on...
Browser
Browser