हिंदी
तमिलनाडु बोर्ड ऑफ सेकेंडरी एज्युकेशनएचएससी विज्ञान कक्षा ११

What are the heart sounds? When and how are these sounds produced?

Advertisements
Advertisements

प्रश्न

What are the heart sounds? When and how are these sounds produced?

संक्षेप में उत्तर
Advertisements

उत्तर

  1. Rhythmic contraction and expansion of heart is called heart beat. The contraction of the heart is called systole and the relaxation of the heart is called diastole. The heart normally beats 70-72 times per minute in a human adult. During each cardiac cycle two sounds are produced that can be heard through a stethoscope.

  2. The first heart sound (lub) is associated with the closure of the tricuspid and bicuspid valves whereas Second heart sound (dub) is associated with the closure of the semilunar valves. These sounds are of clinical diagnostic significance. An increased heart rate is called tachycardia and decreased heart rate is called bradycardia.

shaalaa.com
  क्या इस प्रश्न या उत्तर में कोई त्रुटि है?
अध्याय 7: Body Fluids and Circulation - Evaluation [पृष्ठ १३३]

APPEARS IN

सामाचीर कलवी Zoology [English] Class 11 TN Board
अध्याय 7 Body Fluids and Circulation
Evaluation | Q 22. | पृष्ठ १३३
सामाचीर कलवी Biology (Zoology) [English] Class 11 TN Board
अध्याय 7 Body Fluids and Circulation
Evaluation | Q 23. | पृष्ठ १२९

संबंधित प्रश्न

Describe the evolutionary change in the pattern of heart among the vertebrates.


Sino-atrial node is called the pacemaker of our heart. Why?


What is the significance of atrio-ventricular node and atrio-ventricular bundle in the functioning of heart?


At any given time there is more blood in the venous system than that of the arterial system. Which of the following features of the veins allows this?


Distinguish between mitral valve and semi lunar valve.


Right ventricular wall is thinner than the left ventricular wall. Why?


Select the correct biological term.

Destroyed in the liver and spleen after circulating in the blood for four months.


Select the correct biological term.

The substances which gives red cells their colour.


Which among the followings is correct during each cardiac cycle?


The cardiac impulse is initiated and conducted further upto ventricle. The correct sequence of conduction of impulse is ______.


The walls of ventricles are much thicker than atria. Explain.


Write the features that distinguish between the two.

Open and Closed circulatory system


Write the features that distinguish between the two.

Sino-atrial node and Atrio-ventricular node


Answer the following:

What is specific in the heart of crocodiles among reptilians?


In the diagrammatic presentation of heart given below, mark and label, SAN, AVN, AV bundles, bundle of His and Purkinje fibres.


Cardiac activities of the heart are regulated by ______.

  1. Nodal tissue
  2. A special neural centre in the medulla oblongata
  3. Adrenal medullary hormones
  4. Adrenal cortical hormones

Choose the correct answer from the options given below:


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×