31 Years NEET Previous Year Questions: Body Fluids And Circulation - 3 - NEET MCQ

 The blood of cockroach do not contain RBCs as it is not infact the blood but haemolymph which has some unpigmented free cells in plasma known as haemotocytes which have nothing to do with the transport of gases or respiration.

Haemoglobin of erythrocytes split off into heme and globin. The core of iron in heme is salvaged, bound to protein as hemosiderin and stored for reuse. 

The remaining of the heme group ts degraded to bilirubin a yellow pigment that is released into the blood. Bilirubin is picked up by liver cells which in turn secrete it into the intestine where it is metabolised to urobilinogen.

Rh factor was discovered by Karl Landsteiner. A child of Rh⁺ man will be Rh⁺ whether the mother is Rh⁺ or Rh^–. If the mother is Rh⁺ then there will be no problem but if mother is Rh^– so when the blood of Rh⁺ child (in womb) mixes with the blood of Rh^– mother then some antibodies in mother’s blood are formed against Rh⁺ factor which coagulate the womb blood causing death. If birth takes place then there is a possibility of child death in early years. This in known as erythroblastosis foetalis. In most cases the Ist pregnancy may succeed but after that it fails.

Alkaptonuria (also known as blackurine disease) – excretion of large amount of alkapton in urine which when comes in the contact with light turn black and it is caused by gene mutation. Hematuria – presence of blood or RBCs in urine, proteinuria – presence of protein in the urine

In sickle cell anaemia normal haemoglobin (HbA) gets changed in denatured form of haemoglobin (HbS) in which the haemoglobin molecule’s configuration changes and it changes its shape in low O₂ concentration & become useless for O₂ transportation and RBCs become sickle shaped. It is a genetic disease caused by the denaturation of haemoglobin that is why it is known as Hemolytic anaemia.

Haemophilia is a sex linked disease (linked with X chromosomes). In this disease blood lacks the thromboplastin protein which causes blood clotting during injury. In normal human blood clots in 2-6 min. While in haemophilic human it may take 3 hr. to 24 hr. due to which death may occur. This disease was Ist discovered by Jon Catto in 1803. The most famous family in which the inheritance of this disease was found was the Royal families of Britain & Russia so it is called Royal disease.

Neutrophils are a type of Leucocyte (WBCs) that can take all types of stain (Acid-Basic-Neutral). It is most abundant (60-70% of total WBCs) and most active type of WBCs i.e. they are the most actively phagocytic in nature.

Tricuspid valve is present between right auricle and right ventricle. It has 3 membranous flaps to check the flow of blood in reverse direction. Sinus venosus and right auricle is guarded by sinuatrial value. The opening of left auricle and left ventricle is guarded by bicuspid valve. The opening of ventricle and aorta is guarded by semilunar valves.

A has Antigen A & antibody b so it can have the same blood group or O has no any antigen & antibodies a & b so it is called universal donor.

Because the process of blood clotting starts when prothrombinase (an enzyme formed by Thromboplastin) catalyzes the conversion of prothrombin (an inactive protein in the blood plasma) into thrombin (active protein) and this reaction takes place in the presence of Ca²⁺. Now this thrombin converts fibrinogen into fibrin which makes fibrin threads on polymerization & with blood corpuscles it make blood clot so if Ca²⁺ are removed from blood it’ll prevent clotting. It may also be done by adding some antico-agulants eg. sodium & potassium oxalates in blood as they precipitate Ca²⁺ present in the blood.

Pulmonary artery carries the blood from the right ventricle of the heart to the lungs for oxygenation so it carries deoxygenated blood.

Veins have larger lumen because their middle layer i.e. tunica media which is made up of thick network of circular smooth muscles and elastic fibres in arteries (the wall of blood vessels is made up of tunica externa, tunica media & tunica interna) is thin in veins

The walls of blood capillaries do not possess tunica externa (connective tissue layer containing lymph vessels), tunica media (a thick network of smooth muscle fibres) but only tunica interna (a single layer endothelium of squamous cells)

Vitamin-B₁₂ (cobalamin) promotes DNA synthesis, maturation of erythrocytes and myelin formation. Vitamin-D (calciferol), It is necessary for the formation of healthy bones and teeth.

Vitamin-A (retinol), It is necessary for proper body growth and night vision. Vitamin-C (ascorbic acid), It helps in wound healing, blood formation and absorption of iron.

Blood group A – Antigen-A & Antibody ‘b’ or Anti A or a,
Blood group B – Antigen-B & antibody a or Anti B or b
Blood group AB – Antigen-A & B and no antibody.
Blood group O – No antigen & Antibodies a & b both.

If the child has O blood group – I^o I^o If father has B blood group – I^B I^B or I^B I^o But if father has I^B I^B then child cannot have I^o I^o so father must have I^B I^o.

In foetus liver, spleen, bone marrow, lymph nodes & thymus are the haemopoietic organs (blood forming). In adults most of the blood corpuscles form in the peripheral region of Red bone marrow in long bones.

Endothelium

Heart produces two types of sounds. 1st sound : ‘Lubb’ produced by closure of bicuspid and tricuspid valves. 2nd sound : ‘Dup’ produced by closure of semilunar valves present at the base of aorta to avoid back flow of blood into the ventricle.

Closed circulatory system means blood flows in some definite pipelines in some specific direction in more organized manner than that of open system in which blood does not flow in vessels.

Sino-Auricular node (S.A node) present in the walls of right auricle has a myogenic initiation of heartbeat in a regular fashion and controls the pace of heartbeat called pacemaker.

The inheritance of blood group is determined by some allelic genes which are IA, IB & Io. In one individual two allelic genes are present. Ia & Ib are dominant while Io is recessive in heterozygous condition. So if a child has a blood group O he/she must have IoIo & he/she cannot have the parents of blood group AB & AB/O.

Lymph acts as a middle man between the blood and tissue cells. Lymph is a transparent fluid derived from blood and other tissues which accumulates in the interstital  spaces as the interstitial fluid and it passes on food O₂ from blood to tissue cells and handed ones excretory wastes, hormones and CO₂ from the body cells to the blood.