What is the significance of hepatic portal system in the circulatory system?
Hepatic portal circulation is flow of deoxygenated blood from the digestive organs to’the liver before returning to the heart. In hepatic portal system, the blood enters the liver from two sources; the hepatic artery supplies oxygenated blood from the abdominal aorta and the hepatic portal vein carries deoxygenated blood from the digestive organs. Hepatic portal system is a characteristic feature of all vertebrates. Significance of hepatic portal circulation :
(i) The blood which comes from the alimentary canal contains absorbed food like glucose and amino acids. The excess of glucose in converted into glycogen which is stored in the liver for later use. When an individual feels deficiency of food, the glycogen is converted into glucose and is transferred to the blood stream via hepatic veins.
(ii)Harmful nitrogenous waste like ammo ¬
nia is converted into urea which is later removed by kidneys. Thus the blood is detoxified (purified) of harmful nitrogenous waste.
(iii)Liver produces blood proteins which are put into blood circulation.
Given below are the abnormal conditions related to blood circulation. Name the disorders.
(a) Acute chest pain due to failure of 02 supply to heart muscles
(b) Increased systolic pressure
State the functions of the following in blood
(a) Fibrinogen
(b) Globulin
(c) Neutrophils
(d) Lymphocytes
Complete the missing word in the statement given below:
(a) Plasma without_______factors is called serum.
(b) _______and monocytes are phagocytic cells.
(c) Eosinophils are associated with reactions.
(d)_______ions play a significant role in clotting.
(e) One can determine the heart beat rate by counting the number of_______in an ECG.
Match Column I with Column II.
Column I Column II
(a) Eosinophils (i) Coagulation
(b) RBC (ii) Universal recipient
(c) AB Group (iii) Resist infections
(d) Platelets (iv) Contraction of heart
(e) Systol (v) Gas transport
Answer the following:
(a) Name the major formed. Which part of heart is responsible for initiating and maintaining its rhythmic activity? What is specific in the heart of crocodiles among reptilians?
Explain the advantage of the complete partition of ventricle among birds and mammals and hence leading to double circulation.
Briefly describe the following:
(a) Anaemia
(b) Angina pectoris
(c) Atherosclerosis
(d) Hypertension
(e) Heart failure
(f) Erythroblastosis foetalis
What is the significance of atrio-ventricular node and atrio-ventricular bundle in the functioning of heart?
How will you interpret an electrocardiogram (ECG) in which time taken in QRS complex is higher?
Name the components of the formed elements in the blood and mention one major function of each of them.
Define the following terms and give their location.
(a) Purkinje fibre
(b) Bundle of His
In the diagrammatic presentation of heart given below, mark and label, SAN, AVN, bundle of His and Purkinje fibres.
What is the significance of time gap in the passage of action potential from sino-atrial node to the ventricle?
Given below is the diagrammatic represen-tation of a standard ECG. Label its different peaks.
Write the differences between:
(a) Blood and lymph
(b) Open and closed system of circulation
(c) Systole and diastole
(d) P-wave and T-wave
Differentiate between
(a) Blood and lymph
(b) Basophils and Eosinophils
(c) Tricuspid and bicuspid valve
Write the features that distinguish between the two
(a) Plasma and Serum
(b) Open and closed circulatory system
(c) Sino-atrial node and Atrio-ventricular