applied physiology - book publisher in india and mcqs in her online web ... there are changes in the...

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Applied Physiology

Secrets….

ii Sample copy. Not for distribution.

Publishing-in-support-of,

EDUCREATION PUBLISHING

RZ 94, Sector - 6, Dwarka, New Delhi - 110075 Shubham Vihar, Mangla, Bilaspur, Chhattisgarh - 495001

Website: www.educreation.in

__________________________________________________

© Copyright, Author

All rights reserved. No part of this book may be reproduced, stored in a retrieval system, or transmitted, in any form by any means, electronic, mechanical, magnetic, optical, chemical, manual, photocopying, recording or otherwise, without the prior written consent of its writer.

ISBN: 978-81-923735-8-4

Price: ` 175.00

The opinions/ contents expressed in this book are solely of the author and do not represent the opinions/ standings/ thoughts of Educreation.

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Printed in India

APPLIED PHYSIOLOGY

SECRETS

Dr. R.Vinodha

EDUCREATION PUBLISHING (Since 2011)

www.educreation.in

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ABOUT THE BOOK This book has been designed for medical

students to think critically and intellectually to

enhance their knowledge.

Questions in the form of short notes, reasoning

out, comments and controversies.

Ideal for self assessment, M.D. Physiology

postgraduates, PG basic science and M.B.B.S

examination.

Covers even difficult concepts in Physiology.

Some questions also include clinical perspective

concepts.

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ABOUT THE AUTHOR

Dr. R. Vinodha is professor & HOD

of Physiology at Thanjavur medical

college,Thanjavur.

She graduated M.B.B.S from

Thanjavur medical college in 1987

and completed M.D. (physiology) in 1993 at

Madras medical college, Chennai. She has been

teaching Physiology for the last about 20 years.

She has published papers in national and

international journals. She guides and encourages

students through e-learning by publishing many

articles and MCQs in her online web portal

www.drvinodha.blogspot.com. She was a senate

member of T.N Dr. M. G. R. Medical University

from 2011 to 2014.

http://www.drvinodha.blogspot.com/

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ACKNOWLEDGEMENTS

I am thankful to Dr. P. G. Sankara Narayanan,

Dean, Thanjavur medical college, for granting

permission to write this book. I am grateful to my

parents Mr. A. Ramayyan & Mrs. R. Sakuntala for

their support & guidance. I express my sincere

thanks to Dr. T. B. Uma Devi, former Dean,

Thanjavur medical college & Dr. G. Ambujam,

former Dean i/c, Thanjavur for their

encouragement. I express my thanks & deep

appreciation to all my colleagues in the department

of Physiology, Thanjavur medical college for their

help. I am also grateful to Educreation publishers

who have been very supportive of my endeavour.

vii Sample copy. Not for distribution.

DEDICATED TO

My grandmother (in memoriam),

P.Govindammal

My parents,

A.Ramayyan & R.Sakuntala

My students

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CONTENTS

S.No. Chapter Questions

1. GENERAL PHYSIOLOGY

& BLOOD 1-59

2. GASTROINTESTINAL &

RENAL SYSTEM 60-101

3. ENDOCRINOLOGY &

REPRODUCTIVE

SYSTEM

102-131

4.

RESPIRATORY &

CARDIOVASCULAR

SYSTEM

132-165

5.

CENTRAL NERVOUS

SYSTEM & SPECIAL

SENSES

166-200

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Applied Physiology Secrets

1

1. What is Allostasis?

It is the process of achieving homeostasis through

hormonal or nervous system.

2. What is Lyonisation?

Genes on one of the X chromosomes in somatic

cells of female becomes inactive in early embryonic

life. This is called Lyonisation & it is present only

in somatic cells of females not in germ cells and

also not in males. (Lyonisation – X inactivation is

an epigenetic event) Subsequent daughter cells will

have the same X inactivation. So in fully developed

fetus, some group of cells will have one of the X

chromosomes inactivated, other group of cells will

have other X chromosomes inactivated (Not

uniform). All the cells in females are not

functionally identical.

3. What are Stem cells?

They are unspecialised cells & have two defining

properties.

a) Ability to differentiate into other cells.

b) Capable of self-regeneration.

Dr. R.Vinodha

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4. What are the types of stem cells?

Totipotent - e.g. Zygote

Pluripotent - Cultured human

embryonic stem cell

Multi potent - Hemopoietic stem cell

Oligo potent - Myeloid precursor

Quadripotent - Mesenchymal

Progenitor cell

Tripotent - Glial Restricted

precursor

Bipotent - Murine fetal liver

Unipotent - Mast cell precursor

Nullipotent - Terminally differentiated

cell - eg. RBC.

5. Name the Embryonic stem cell marker (ESC)

a) Oct-3 or Oct3/4-Transcription factor

b) SSEA-Stage specific embryonic antigen.


3

6. Sweet tooth in the exercising muscle –

Comment.

Muscle cells insert more glucose carriers in their

plasma membrane in response to exercise. During

exercise the rate of glucose transport into exercising

muscle increases. Usage of glucose & other

nutrients also increases. Glucose uptake by cells is

accomplished by glucose carrier in the plasma

membrane.

7. What is the normal Adipose tissue blood flow

(ATBF)?

In fasting 3ml/100mg/tissue/mt.Fasting, exercise,

stress, β adrenergic stimulation increases Adipose

tissue blood flow (ATBF).

8. What is Junk DNA?

A Portion of DNA sequence of a Chromosome or a

genome that do not encode protein sequences. It is

also called non coding DNA. Much of this DNA has

no biological function.

Dr. R.Vinodha


9. What is micro gravity/Near-Zero gravity?

Micro gravity/ near-Zero gravity environment is

present in space that can affect the body in 3 major

ways.

a) There are changes in the circulatory

system.

b) There is a shift in body fluids towards

head

c) There is a reduction in weight bearing

forces in the body.

Physiological effects of space flight – space

sickness, disorientation, migration of fluids to upper

body, muscle atrophy, bone deterioration,

lengthening of spine, backache etc...

10. What is staleness?

Staleness means over training. It occurs in 10 – 20%

of athletes. Two clinical forms have been described.

a) The most common form is Parasympathetic

form – (Addisonoid for adrenal insufficiency

patterns) characterised by Predominance of

vagal activity during rest & exercise.

b) The less common form is Sympathetic form

(basedowian for thyroid hyper function pattern)

characterised by increased sympathetic activity

during rest, hyper excitability, restlessness &

impaired exercise performance.


5

11. What is the formula for calculating serum

anion Gap?

(Na+

+ K+

) – (Cl−

+Hco3−

).The normal value is 6-

12 mmol/lt.

12. Why do mitochondrial diseases cause

myopathy?

Muscles derive energy via oxidative

phosphorylation. A mutation in mitochondrial DNA

impairs oxidative phosphorylation.

13. Reasoning out: single gene traits obey All or

None law.

Single gene traits are discrete or qualitative and

providing All or None phenotype (Normal vs.

affected) whereas multiple genes that regulate

height, skin colour results in continuously varying

phenotype. (Skin colour is controlled by 8 genes).

Dr. R.Vinodha


14. What is telomerase?

It is an enzyme and adds bases to the end of

telomeres. In young cells, telomerase keeps

telomere from wearing down too much. But as cells

divide repeatedly, there is no enough telomerase, so

the telomere becomes shorter and the cells age.

Telomerase remains active in sperms and eggs.

15. Compare Somatic and Germ cell.

Somatic cells are: ‘body cells’ (SOMA=body),

diploid; have 46 chromosomes; undergoes mitosis.

Germ cells are: reproductive cells, (ovum, sperm),

haploid; have 23 chromosome; undergoes meiosis.

16. What is genetic anticipation?

It is a phenomenon in which symptoms of genetic

disorders occur at an early stage as the disorder is

passed from one generation to the next. In

molecular term, anticipation is due to the expansion

of a tri-nucleotide repeat sequence in the DNA. It is

common in Huntington’s disease and myotonic

dystrophy. This phenomenon also occurs in the


7

Fragile X syndrome, the most common inherited

form of mental retardation.

17. What is the important implication of G6PD

gene?

The G6PD gene is X linked. In males, only one

G6PD gene is present (they are hemizygous for this

gene) so, they must be either normal or G6PD

deficient. In females, there are 2 G6PD genes. They

can be either normal or deficient (homozygous), or

intermediate (heterozygous). As a result of X –

inactivation, some heterozygous may be affected

just like males.

18. What is the significance of Brown Adipose

Tissue (BAT) in humans?

BAT depots are abundant in newborns, but BAT

rapidly decreases in size during childhood. It is now

found that, significant amount of active BAT depots

are present in adult humans and are involved in

energy homeostasis &regulation of adiposity. Adult

human BAT can be recruited by chronic cold

exposure and TRPV1 agonists (found in food

ingredients such as capsaicin (anti-obesity agent).

Dr. R.Vinodha


19. What is BAT plasticity?

Several recent articles indicate that Trans

differentiation from mature white adipocyte into

brown adipocyte may occur in response to chronic

cold exposure in animals.

20. What are the factors affecting BAT

development and regulation?

BAT development and functions are regulated by

hormonal factors derived from various tissues like-

CNS: catecholamine(+), orexin(+)

Heart: ANP/BNP (+)

Macrophage: catecholamine (+)

Skeletal muscle: TGF ß (-), Myostatin (-)

Liver: bile acid (+), FGF-21(+), fibroblast growth

factor.

21. What are the 3 modes of exocytosis?

Full-collapse fusion, kiss-and-run, and compound

exocytosis.

22. What are the 3 modes of endocytosis?

Classical clathrin-dependent endocytosis, kiss-and –

run, and bulk endocytosis.


9

23. Blood is a specialised body fluid, but why it is

considered as a connective tissue?

In terms of anatomy and histology blood is

considered a specialized connective tissue, because

embryo logically it has the same mesodermal origin

like connective tissue and it contains the potential

molecular fibre in the form of fibrinogen.

24. What is genetic imprinting?

It is an epigenetic alternation. A form of allele

activation and inactivation that depends upon which

parent a particular chromosome came. Only the

allele on one chromosome, either maternal or

paternal in origin, is expressed. The inactive gene is

generally methylated. (The methyl group CH3

‘silence’ certain genes). At least 600 human genes

are imprinted. There are 2 large imprinted regions,

one on chromosome 11 p15.5 and the other on

chromosome 15q12. A striking example of genomic

imprinting involves 2 different syndromes that arise

from small deletion of the same region of

chromosome 15. Prader-willi syndrome: loss of

paternal gene and the maternal gene is silenced due

to imprinting. Angel man syndrome: Loss of

maternal gene, and paternally imprinted gene in the

same region.

Dr. R.Vinodha


25. What is mitogenic signalling pathway?

Mitogenic signalling molecules activate signalling

cascades that promote cell growth, proliferation and

differentiation. One of the important signalling

pathways that transduce mitogenic signalling is the

MAPK pathway (mitogen activated protein

kinase).It operates in the absence of second

messenger and responds to stimuli such as

mitogens, osmotic stress, heat shock and

proinflammatory cytokines. They regulate cell

functions such as proliferation, gene expression,

differentiation, mitosis, cell survival and apoptosis.

26. What is heat syncope?

It occurs when a body temperature is above 40°C

(104°F). It is a circulatory failure resulting from

pooling of blood in peripheral veins (heat causes

vasodilatation) subsequently venous return and

diastolic filling of heart decreases resulting in

↓cardiac output and blood pressure. Fainting and

loss of consciousness occurs because of low blood

pressure.

27. What are auto receptors?

Auto receptor is a type of presynaptic receptor and

it provides feedback control in signal transduction.

For e.g. norepineprine acts on α2 presynaptic


11

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At Educreation Store

www.educreation.in

ABOUT THE AUTHOR

She has been teaching Physiology for the last 20 years. She has published papers in national and international journals. She guides and encourages students through e-learning by publishing many articles and MCQs in www.drvinodha.blogspot.com She was a senate member of T.N. Dr. M.G.R. Medical University from 2011 to 2014.

Dr. R. Vinodha is professor & Head of Department of Physiology at Thanjavur medical college, Thanjavur. She graduated M.B.B.S from Thanjavur medical college in 1987 and completed M.D. (Physiology) in 1993 at Madras medical college, Chennai.

Also available as an eBook

ACADEMIC

(Dr. R. Vinodha)

EDUCREATION PUBLISHING (Delhi)

www.educreation.in

applied physiology - book publisher in india and mcqs in her online web ... there are changes in the...

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