Advertisements
Advertisements
Question
Give scientific reason.
Human heart is called as myogenic and autorhythmic.
Advertisements
Solution
- The heart shows autorhythmicity because the impulse for its rhythmic movement develops inside the heart. Such a heart is called myogenic.
- During development, certain heart muscle fibres become autorhythmic (self-excitable) and begin to generate impulses.
- These autorhythmic fibres have two vital functions: they operate as a pacemaker and set the heart's beat.
- They also form a conducting system for the conduction of nerve impulses throughout the heart muscles.
APPEARS IN
RELATED QUESTIONS
What is hypertension? Why is it caused? What harm can it do?
Fill in the blank.
In human body, heart is located on the _____ side of the chest cavity.
Given alongside is a highly diagrammatic sketch of the internal structure of the human heart:
(i) Name the parts numbered 1-11.
(ii) What is the main difference in the quality of blood contained in parts 6 and 7?
Draw the diagram external features of the heart.
Choose the Odd One Out:
The phase of contraction of heart is termed as ______.
In between which layers of pericardium, pericardial fluid is present?
Blood capillaries show the presence of ______
When a person suffers from chest pain, the doctor immediately takes an ECG. Visit a doctor and get information about ECG. You may even look up an encyclopaedia or the internet.
Given below is a diagram of the external features of the human heart. Study the figure and answer the questions that follows:
 |
- Label the guidelines shown as 1 to 6 in the figure.
- Write the important role of parts 5 and 6.
- Name the chamber of the heart which collects blood from the lungs through a blood vessel. Also write the name of the blood vessel.
- Write one structural and one functional difference between the blood vessels 4 and 5.
- What happens when there is a blockage in any coronary artery or any of their branches?
