1 think this in terms of pecking orders of capital structure
this part is cleaned up and moved here:
blog.wenxuecity.com/myblog/67448/201501/7671.html
2 think of term structure of interest rate - ie bond of different maturity requires different yield
a. long-term bond pays more per year typically since it ties up your money longer; however short term interest is more sensitive to monetary policy;
b. when rate goes up, rates at all maturity go up; 90% of interest rate movement is parallel move; for same size interest rate movements, long-bond will move much more due to "duration" effect, ie you are stuck/lucky for a long time for existing coupon rate when market yield changes.
c. then there is "tilt" and "twist", which accounts for the remaining term structure movements.
just my 2c