Apex of the heart is formed by -

Ans. is 'c' i.e., Left ventricle o The heart has following borders and surfacesA) Bordersi) Right border:- Formed by right atrium.ii) Left border (obtuse margin):- Formed mainly by left ventricle and partly by left auricle (in its upper most part).iii) Inferior border (acute margin):- Formed mainly by right ventricle and partly by left ventricle near apex.iv) Upper border:- Mainly by left atrium and partly by right atrium where SVC enters.v) Apex:- Formed by left ventricle.B) Surfacesi) Anterior (sternocostal) surface:- Formed mostly by right ventricle (major) and right auricle and partly by left ventricle and left auricle.ii) Inferior (diaphragmatic) surface:- It is formed by left ventricle (left 2/3) and right ventricle (right 1/3). It is traversed by posterior interventricular groove (PIV) containing PIV branch of RCA.iii) Base (posterior surface) :- Formed mainly by left atrium and partly by right atrium. It is separated from T5 to T8 vertebrae by pericardium, oblique pericardial sinus, esophagus and descending thoracic aorta.iv) Right surface:- Mainly by right atrium.v) Left surface :- Mainly by left ventricle and partly by left auricle.