Question

Write the features tha distinguish between the two.

(i) Plasma and serum

(ii) Open and closed circulatory system

(iii) sino-atrial node and atrio-ventricular node

Answer 1

(i) Difference between plasma and serum are as follows

$\begin{array}{cc}\text{Blood Plasma}& \text{Blood Serum}\\ \text{It is the fluid without blood corpuscles.}& \text{It is liquid without clotting elements.}\\ \text{It is faint yellow in colour.}& \text{It is pale yellow.}\\ \text{It has fibrnogen and other clotting}& \text{It does not have fibrinogen and other}\\ \text{materials.}& \text{clotting materials.}\\ \text{It takes part in blood clotting.}& \text{It does not take part in blood clotting.}\end{array}$

(ii) Difference between open and closed circulatory system are as follows

$\begin{array}{cc}\text{Open Circulatory System}& \text{Closed Circulatory System}\\ \text{Open circulation occurs in arthopods and}& \text{It occurs in annelids (earthworms, some)}\\ \text{molluscs.}& \text{molluscs and all vertebrates}\\ \text{The blood is not completely enclosed within}& \text{In closed circulatory system, materials move}\\ \text{vessels, the heart pumps blood through}& \text{between the blood and interstitial fluid}\\ \text{arteries into large cavities or sinuses, where}& \text{through thin walls capillaries.}\\ \text{it mixes with the interstitial fluid and bathes}& \\ \text{the cells of the body}.& \\ \text{Circulation is slower in an open system,}& \text{Blood flows a high pressure in a closed}\\ \text{because some of the blood pooled in}& \text{circulatory system.}\\ \text{sinuses and, the heart is unable to build up}& \\ \text{enough pressure to make the blood flow}& \\ \text{rapidly}& \\ \text{Respiratory pigment, if present, is dissolved}& \text{Respiratory pigment is present which may}\\ \text{In the plasma, no red corpuscles are present}& \text{be dissolved in the plasma but is usually}\\ & \text{contained red blood corpuscles.}\end{array}$

(iii) Difference between sino atriol node and artrio-ventricular node are as follow

$\begin{array}{cc}\text{SA Node}& \text{AV Node}\\ \text{It is the small mass of specialised muscle}& \text{It is situated in the fibrous ring between the}\\ \text{cells in the wall of right atrium near the}& \text{right atrium and ventricle of the heart.}\\ \text{opening of vena cava.}& \\ \text{It initiates and maintains the heart beat}& \text{It is the pathway through, which electrical}\\ & \text{impulses can pass}.\end{array}$