TEXTBOOK ANSWERS AND SOLUTIONS ChapteR-18-Body Fluids & Their Circulation CBSE-CLASS-XI-BIOLOGY

1) Name the components of the formed elements in the blood and
mention one major function of them?
     Components of formed
elements are –
     Red blood cells or
Erythrocytes, WBC, leucocytes & platelets are collectively called formed
elements they constitute nearly 45% of blood
     Major functions –  I) RBC: Transport of gases (o2
& Co2)
                   ii) WBC:
Fight against infection
                   iii) Platelets:
Fill up the blood clotting.
2)   Matching =
              Column I                Column II
          a) Eosinophills                            I) Coagulation
          b) RBC                       ii) Universal Reagent
          c) AB Group                  iii) Resist Infection
          d) Platelets                 IV) contraction of heart
          e) Systole                   v) Gas transport
     Ans       (a)
– (iii)]
          (b) – (IV)
          (c) – (ii)
          (d) – (I)
          (e) – (v)
1) Why
do we consider blood as a connective tissue?
     As it consists of
fluid matrix plasma & the formed elements namely red blood corpuscles, RBC
& platelets – so it functions as a connective tissue.
4)   What do you mean by
double circulation? What is its significance?
     It includes systematic
and pulmonary circulations. The flow of oxygenated blood from the heart to all
parts of body & deoxygenated blood from various parts of blood of the heart
is called systemic circulation. The flow of de-oxygenated blood from the heart
to the lungs and return of oxygenated blood from the lungs to be heart is
called pulmonary circulation.
     Significance = It checks
the mixing of oxygenated blood & deoxygenated blood
     Oxygenated blood
carries more oxygen & deoxygenated blood carries more carbonic – oxide for
5)   A) Difference between
blood & lymph
Blood
1) It consists of plasma,ertythrocytes
leucocytes & platelets
2) Reds due to presence of hemoglobin
& erythrocytes
3) Glucose conc. In less
b)
Open system of circulation
I) Blood does not remain confined in
the blood vessels& comes to certain spaces
ii) Blood flows at sow pressure
iii) It is less efficient
C)   Systole
i)     
The contraction of cardiac (heart)
chambers in called systole
ii)   
Blood is pumped out of the
cardiac chambers
iii) 
The valves is are closed to  prevent backflow of blood
d)  P-wave
This wave represents depolarization of
atria (atria contraction)
Blood is pumped into the ventricles
Lymph
It consists of plasma & leucocytes
It is colorless
Glucose conc. To high
Closed
system of circulation
Blood remains confined to the blood vessels
Blood flows at high process
It is max efficient
Diastolic
The relaxation of cardiac (heart)
chambers is called diastolic
Blood is received in the cardiac
chambers
The valves are opened to allow entry of
blood
T
– Wave
It represents ventricular repolarisation
(Ventricular relaxation)
Blood is received by the atria
6) Why do we call our heart myogenic/
     Cardiac impulse
originates in the heart itself at a patch of modified heart muscles Impulse
spreads over the heart via modified cardiac muscle cells. Heart removed from
the body continuous to beat if given nourishment & proper condition.
7) Sino– atria node is called the pacemaker of our heart why?
     The S.A. node is
located in the wall of sign auricle slightly below the opening of the super
venacava. It has a unique property of self excitation which enables it as to
act as the pacemaker of the heart. It spontaneously initiates waves of
contraction which spreads over both the auricles more or less simultaneously
along the muscle fibers that fan out from the pacemaker.
8) What is the significance of atrio- ventricular node and atrio
– ventricular bundle in the functioning of heart?
     AVN is mass of neuron
– muscular tissues and is situates in the wall of right atrium. The AV node
picks up the wall of contraction originated by SAN. Bundle of his is a mass of
specialized fibers which originates from the AV nodes. The his Bundle and purkinje
fibers convey impulse of contraction from the AV node to the muscles of the ventricles.
9) Define a cardiac cycle? & Cardiac output?
     Cardiac cycle = A regular consequence of three events auricular
                        Systole
is ventricular systole
                        Joint
diastole
Cardiac output = the amount of blood pumped by hearts / min is
called cardiac output or hearts output
10) Explain heart sounds
Two
types of sound



 


              First sound                           Second Sound
     This is caused by the
closure of           this is caused by
closure of
     The bicuspid &
tricuspid valve             semilunr
values
          (Lubb’ – low
pitched)                 the 2nd
sound = dup
11) What is the importance of plasma proteins?
     = prevents of blood
loss
          = Body immunity
          = maintenance of
PH
          Transport of
certain Materials
12) Describe the
cuolutionary changein the patterns ofheart among westbrahes.
     The circulatory system
is of two types = open & closed
     In open circulatory
system the blood is pamped out by the heart passes through large vessets inter
open. Opaces or body cavities called sinses
     It is preson in
Annetids & chordahes
     All vertibrakes balue
muaculor heart pink poses 2 chamber 
     Hear omphibio have 3
chamber heart w.m 2 atria and one ventricte Reptiles excpt crocodile have 3
chambered with 2 arial & one vintrice.
     In fishes the heart
pumpsout de-oxygenared blood which is oxygenated by the gills & sent to the
body parts from where de-oxygenated blood is carried to the heart . it is
called single circulation in lung fishes, amphibians & reptiles the left
atrium gets oxygenated blood from the gills/lungs/shin/bucc /harygeal carry
& the right atium receives the de-oxygenated blood from other body parts.
Both oxygenated & de-oxygenated blood gets mixed up in single
     Ventricle within pumps
out mixedblood. This iscalled incomplete double circulation
     In crocodiles, brids
& mammals the oxygenated & de-oxygenated blood is reciessed by left
& rigtht aria respectively passes on to the left & right umtri. Now
oxygenated & de-oxygenated blood doesn’t get mix. It is called double
circulation
          [ Figur on page
US 92 ]
13) Draw a standerd ECG & explain the different segment in
it
     Diagram = prefer to
NCERT
     1) pwave :    is a small upward wall that represent electrical
excitation or the arial depatasexation which leads to entracise of both the
aria (arial contraction) It is caused by the activation of SA Node . the
impulses of contrasis starts from SA note & spread throughout the atria.
     2) QRS wave – begins
after a freaction of second of the pure . it begins as a samall downward
deflection (Q) & continues as large upstages ® & triangular wave,
ending as downward wave(s) at its base . It represents ventricular
depolarization.
2) Twle
_ isdone shaped which represents craticular repolaniati’s ventrice from the
depolorisation stake is called the repolarisation wave. The end of the I-wave
marks the end of systole.