🏆 Andhra Pradesh Topper: Sravani Chowdary (230 pts)
🏆 Arunachal Pradesh Topper: Yomto Tana (238 pts)
🏆 Bihar Topper: Anand Singh (229 pts)
🏆 Chhattisgarh Topper: Devesh Sinha (382 pts)
🏆 Goa Topper: Prathamesh Rodrigues (187 pts)
🏆 Gujarat Topper: Jigar Shah (412 pts)
🏆 Haryana Topper: Sonia Chaudhary (489 pts)
🏆 Himachal Pradesh Topper: Shikha Rana (84 pts)
🏆 Jammu & Kashmir Topper: Suhail Bhatt (447 pts)
🏆 Jharkhand Topper: Anjali Munda (177 pts)
🏆 Karnataka Topper: Kavya Rao (143 pts)
🏆 Kerala Topper: Sreejith Mathew (118 pts)
🏆 Madhya Pradesh Topper: Muskan Jain (164 pts)
🏆 Maharashtra Topper: Omkar Pawar (333 pts)
🏆 Manipur Topper: Premjit Thangjam (52 pts)

Body Fluids and Circulation

Home > Zoology (37) > Body Fluids and Circulation (2)
Q1. Which layer of blood vessels is comparatively thin in veins but thick in arteries?
  • Tunica externa
  •  Tunica media
  •  Tunica intima
  • Endothelium
Q2. What causes the first heart sound (lub) during a heartbeat?
  • Closure of the semilunar valves at the start of ventricular diastole
  • Opening of the semilunar valves to allow blood flow to the arteries
  • Rapid filling of the ventricles from the atria
  • Closure of the tricuspid and bicuspid valves during ventricular systole