Separation of Powers and Checks and Balances: Kya Farq Hai?

Yaar samajh nahi aaya, kuchh time pehle CLAT PG ka paper diya tha, aur abhi tak maine kya samajh liya hai ki separation of powers aur checks and balances kya farq karte hain? Sabhi ke kahne mein yehi hai ki dono ek doosre ke liye zaroori hain, lekin maine socha ki yeh ek hi cheez hai, to phir kya difference hai?

Maine socha ki yeh cheezein saamantar hain, jab ki separation of powers ke baare mein kaha jata hai ki powers ko trinomaal karna hai aur dono aur dono ko apne area mein kam karna hai.