Monday, 28 April 2014

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. 
Written By Badal Paul
The author is a passionate blogger, writer and educationalist. This blog is created to ease troubles of the Cbse students. The author holds multiple blogs and the writer of the Novel KALCHAKRA, OOM AND THE CHOSEN FIVE.