Banaras Hindu University (BHU) 2008 B.Sc Zoology (hons)part 3 - Question Paper

zoology

mammalian endocrinology and developmental biology

full marks 75 hours three

coloured diagram s are permitted
section___________A

( mammalian endocrinology)

( marks 37 1/2)

ans 3 ques. including ques. one is compulsory
1.)
(A)mention weather the subsequent statements are actual or false, giving in brief in support of your answer[ marks 3*2]


(1)glucagon is the hypoglycemic agent.

(2) adrenal cortex is steroidogenic
.
(3) chief cells are source of parathormone.


(B)match the terms in column a with those in column b [marks3*1/2]

column a column b

(1) LH (a) acidophils

(2) Addison's disease (b) hypothalamus

(3)CRH (c) pars distalis

(d) adrenal cortex


2.describe biosynthesis ,biological actions and control of secretion of hormones of adrenal cortex


3.describe in brief: [ marks seven 1/2]

(a) biosynthesis of biosynthesis

(b) mechanism of steroid hormone action


4.give a flow diagram showing biosynthesis of ovarian steroids. define their biological actions[marks 15]

5.write short notes on the subsequent [ marks 5*3]


(a)G proteins

(b)calcitonin

(c)pheromones

part ___________B


( developmental biology)

( marks 37 1/2)


ans 3 ques. including ques. one is compulsory

1.(A)mention weather the subsequent statements are actual or false, giving in brief in support of your ans [ marks 3*2]

(a)gastrulation in frog embryo is initiated at the future ventral side of the embryo


(b)cleavage of sea urchin eggs is radial holoblastic kind.

(c)zona pellucida in mammals plays a role analogus to that of the vitelline envelope

(B)____ choose the accurate right choice from the subsequent and justify your choice[marks one 1/2]

at the cellular blastoderm stage od Drosophila stage every cell is

(a)determined in its fate

(b) differentiated

(c) totipotent

(d)pleuripotent

2.(a) define the kinds of cellmovements through the primitive streaks during the gastrulationin chick which become the major body parts [marks 8]


(b)what are the extra embryonic membranes that support and nourish the mammalian embryo? [marks 7]
discuss biological role of every 1 of them



3.(a)describe the hierarchy of the gene that determine antero-posterior polarity of embryo of embryo in drosophila.....................................................................................................[marks10]

(b)identify various steps in which oogenesis and spermatogenesis differ.[ marks 5]


4.___.write short notes on the subsequent [ marks 5*3]


(a) spemann's organizer

(b) cortical reaction

(c) fate map and cell lineage studies

5.(a) discuss with the help of suitable diagrams, the process of development of vertebrate eye. which gene is believed to a play key role in the process.[ marks 10]

(b) define the formation and significance of gray crescent.[ marks 5]

Earning:   Approval pending.