Biology
When are the sounds "LUBB" and "DUP" produced respectively during heart beat?
Answer
The first sound "LUBB" is produced when the atrio-ventricular (tricuspid and bicuspid) valves get closed sharply at the start of ventricular systole. The second sound "DUP" is produced when at the beginning of ventricular diastole, the semilunar valves at the roots of aorta and pulmonary artery get closed.
Related Questions
Note the relationship between the first two words and suggest the suitable word/words for the fourth place:
(a) Lub : Atrio-ventricular valve :: Dup : ……………
(b) Coronary artery : Heart :: Hepatic artery : ……………
(c) RBCs : Polycethemia :: WBCs : ……………
(d) WBCs : …………… :: RBCs : Erythropenia
(e) Chest pain : Angina pectoris :: Heart attack: ……………
Enumerate the structural differences between white blood cells and red blood cells.
Match the items in column A with those in column B. Rewrite the correct matching pairs.
Column A Column B (a) SA node Plasma (b) Defective haemoglobin in RBC Serum (c) Muscle fibres located in the heart Pacemaker (d) The liquid squeezed out of blood during clotting Sickle cell anemia (e) Never tires, keep on contracting and relaxing Purkinje fibres (f) Cardiac cycle Cardiac muscles (g) Liquid part of the blood without corpuscles 0.85 sec The table below is designed to indicate the transport of certain substances in our body. Fill in the blanks with suitable answers.
Substance From To …………… Lungs Whole body Carbon dioxide ……… …………… Urea ………. ………… Digested carbohydrates Intestine ………….. ………… ………… Target organs