BIO. P1 cie Que.

[sweetie]

Q1. A person has a heart rate of 70beats per min. and a stroke volume of 80cm3?
what is approx. vol. of blood returning to the heart per min. from the left pul. vein only???

thanx 4 any help

[cashem'up]

hey listen........is it....5600

[nid404]

Ohk...Stroke volume=80cm3
since the volume is equally divided between the two ventricles, left ventricle will have 40cm3

we're finding partial cardiac output=heart rate X stroke volume of the particular ventricle (dm3)
                                              =70 X 40/1000
                                              = 2.8L/min

[tmisterr]

actually stroke volume is the volume pumped out by EACH ventricle in a single beat so there is no need to divide by 2 (plus you can't be sure they are pumping out the same amount of blood since left ventricle has thicker walls) so it will just be 80/1000*70=5.6 dm³  min^-1

[nid404]

Yes..my bad..it's each ventricle that pumps 80cm3.

[sizbeauty]

Q1.how many diff polypeptides,each consisting of r aminoacids,can be made if the no of diff aminoacids available is n??
Q2.if there were 34 aminoacids and DNA only contained two types of nitrogenous bases,what would b the mininmum no of bases per codon that could code for proteinz?
Q3.what is the theoretical num of diff dipeptides that may b assembled frm 12 diff aminoacids?
Q.7(nov 1999 cie,plz explain de diagram in this mcq) n Q11 of nov 1999 as well
(tell me de ans of dese mcqz wid explanation plzzz)
thanx in adv..plz rply quickly

[tmisterr]

q1 there are n amino acids combing to form poly peptides of length r so they can combine in n^r different ways

q2 I would say 6, since they are 2 bases only, then they have to join in groups of six to produce 34 amino acids. they can join in 2⁶ different ways to make 64 amino acids.


q3 dipeptide contains 2 amino acid so 12 amino acids could join in 12² different ways to form 144 amino acids

q7 upload the paper

[sizbeauty]

@ tmisterr:
q2 I would say 6, since they are 2 bases only, then they have to join in groups of six to produce 34 amino acids. they can join in 26 different ways to make 64 amino acids.

thx alot for de hlp...i gt 1 n 3 but i don't understand tht y do aminoacidz hav to join in groupz of six(is it a rule or wht)??plz explain this point n nov 1999 ppr is nt available on net,i gt it frm ma teacher.anywyaz thx

[sanity_master]

Yes..my bad..it's each ventricle that pumps 80cm3.

the stroke volume is the volume of blood that is pumped per beat, by the 2 ventricles, thats y we get the cardiac output (the total volume of blood pumped by the heart) per minute. isnt this right?

the answer to the 1st Q> approx. vol. of blood returning to the heart per min. from the left pul. vein only? as it is the left pul. veins only, it would be half of the heart, meaning, half of the blood.......and as the total is 5.6 Liters, the half would be 2.8 liters

the answer would be 2.8 L/min (its in OCT/NOV2001 Q29)......

[tmisterr]

@ tmisterr:
q2 I would say 6, since they are 2 bases only, then they have to join in groups of six to produce 34 amino acids. they can join in 26 different ways to make 64 amino acids.

thx alot for de hlp...i gt 1 n 3 but i don't understand tht y do aminoacidz hav to join in groupz of six(is it a rule or wht)??plz explain this point n nov 1999 ppr is nt available on net,i gt it frm ma teacher.anywyaz thx

no no not a general rule, usually its a triplet code (e.g CAA would code for an amino acid), but now instead of 3 bases there are only two bases so if they join in groups of 2, they would only be 4 amino acids, if they join in groups of 3, they would only be 8 amino acids, if they join in groups of 4, only 16 amino acids, in groups of 5, only 32 amino acids but if it is in groups of six, then they can make 64 amino acids, since the minimum is 34, this is the answer.

[tmisterr]

the stroke volume is the volume of blood that is pumped per beat, by the 2 ventricles, thats y we get the cardiac output (the total volume of blood pumped by the heart) per minute. isnt this right?

the answer to the 1st Q> approx. vol. of blood returning to the heart per min. from the left pul. vein only? as it is the left pul. veins only, it would be half of the heart, meaning, half of the blood.......and as the total is 5.6 Liters, the half would be 2.8 liters

the answer would be 2.8 L/min (its in OCT/NOV2001 Q29)......

Might be sanity....according to my text book though, stroke volume is the volume pumped out by each ventricle, not by both, and i just double checked on the internet but if the marking scheme says 2.8, i guess i was wrong