The following events occur when a mammalian immune system first encounters a pathogen. Which shows the correct sequence in which they occur?

I.   Pathogen is destroyed.

II.  Lymphocytes secrete antibodies.

III. Antigenic determinants from pathogen bind to antigen receptors on lymphocytes.

 IV.  Lymphocytes specific to antigenic determinants from pathogen become numerous.

V.   Only memory cells remain.

#Question id: 11591

#Unit 6. System Physiology – Plant

Gibberellins biosynthesis completes in almost three organelles

#Question id: 11592

#Unit 6. System Physiology – Plant

Gibberellin biosynthesis precursor is____

#Question id: 11593

#Unit 6. System Physiology – Plant

Following are given stages of gibberellin biosynthetic pathway;

a) Geranylgeranyl diphosphate (GGPP) is converted to ent-kaurene  via copalyl diphosphate (CPP) in endoplasmic reticulum

b) In the endoplasmic reticulum, conversion of ent-kaurene into GA12 or GA53 depending on whether the GA is hydroxylated at carbon 13

c) the conversion of GA12 or GA53 into other GAs in cytosol proceeds with a series of oxidations at carbon 20

d) GA20 is then oxidized to the active gibberellin, GA1, by a 3β-hydroxylation reaction

Which of the following is the correct statements of GA biosynthesis?

#Question id: 11594

#Unit 6. System Physiology – Plant

Given some compounds that are the first stage inhibitor of gibberellin biosynthesis except?

#Question id: 11595

#Unit 6. System Physiology – Plant

Paclobutrazol and other inhibitors of P450 monooxygenases specifically inhibit the stage of gibberellin biosynthesis

#Question id: 11596

#Unit 6. System Physiology – Plant

Which enzyme catalyzes  all the reactions involving the successive oxidation steps of carbon 20 between GA53 and GA20, including the removal of C-20 as CO2?