BLOOD PRESSURE MONITOR

You may use the same circuit.
Basically input impedance and noise levels would be different for jfet and bipolar.

and what about frequency resopnce if its 1-4 hz would it matter for bipolar or jfet

At such low frequencies the input noise density would be a bit greater for jfet-input opamps.
Don't worry too much about these now.Keep looking for the best precision opamp you can lay your hands on.
And meanwhile experiment with various locally available alternatives.Use a socket so that you can easily swap different opamps.
Use precision 1% or better resistors in the opamp ckt to keep overall noise low.

i came uopn various op amps.ive noticed that some have single supply and some hav doual ie+_5 V.Why?

if the input signal to be amplified or compared ( that is mostly why op-amps are generally used) tends to fall into the negative region ( below 0V), then u invariably require a dual supply op-amp for the purpose to preserve the input information through to the output.
single supply op-amps can be used for the other cases where the input is strictly restrained in the positive voltage region.The single supply op-amps also tend to consume less current and are used in battery operated appliances where power consumption is a major issue.

is it like that u got to use if u measure input impedance within some range.i used lt1014 on proteus and got result as in picture.i have a question that adc 0831 can measure when woltage rises on above any spicified voltage.what is input impedence

please attach Proteus file

i implemented ossilation geting using filters on LT 1014.out put was not ossilations.i mean there was no out put in some cases there was slight 1 or 2 osilations.Now i want to know that as in the source web he is usin MPX2050 and ad620 but im using scx15dn and lt 1014 for sensor interface.as datasheet of scx15dn shows that it can b used for BP.dose it make any difference if i use opa 2277 like he did with ad620.to use opa 2277 is it necessary to use dual power supply.the ossliations seen on CRO on first stage ie out put of schematic given in scx15dn for BP measurement range in micre volts

i am able to get lf353.do i have to use in the same way as opa2277.Is it necessary to supply +5v and -5v?acn it be like +5v and gnd

ive performed a proteus chk.i think opa2277 and lf353 are same in characterstics.Please varify