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Posted by Neil Modi 5 years ago (10008913)
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Posted by Neil Modi 5 years ago (10008913)
- 1 answers
Yogita Ingle 5 years ago (2577571)
Structure of Human Heart
- The heart is a muscular organ covered by a double membrane called pericardium.
- The pericardial fluid of the pericardium lubricates the heart.
- The heart is divided into four chambers — two upper atria and two lower ventricles.
- The inter-atrial septum separates the two atria and the inter-ventricular septum separates the two ventricles.
- The atrium and the ventricle of each side are separated by the atrioventricular septum.
- Superior and inferior vena cavae open into the right atrium.
- The right ventricle opens into the pulmonary artery.
- Four pulmonary veins open into the left atrium.
- The left ventricle opens into the aorta.
- The opening between the right atrium and right ventricle is guarded by the tricuspid valve.
- The opening between the left atrium and left ventricle is guarded by the bicuspid (mitral) valve.
- The opening of the right ventricle into the pulmonary artery and the opening of the left ventricle into the aorta is guarded by the semilunar valves.
Posted by Neil Modi 5 years ago (10008913)
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Yogita Ingle 5 years ago (2577571)
- Two blood groupings are done
- ABO and
- Rh
ABO grouping
- ABO grouping is based on the presence or absence of two surface antigen on the RBCs namely A and B.
- The plasma of different individuals contains two natural antibodies.
- The distribution of antigens and antibodies in the four groups of blood, A, B, AB and O.
- The blood of a donor has to be carefully matched with the blood of a recipient before any blood transfusion to avoid severe problems of clumping, which leads to destruction of RBC.
- Group ‘O’ blood can be donated to persons with any other blood group and hence ‘O’ group individuals are called ‘universal donors’.
- Persons with ‘AB’ group can accept blood from persons with AB as well as the other groups of blood, and such persons are called ‘universal recipients’.
Rh grouping
- The Rh antigen similar to one present in Rhesus monkeys is also observed on the surface of RBCs of majority of humans, hence the antigen is known as Rh antigen.
- The individuals having Rh antigen are called Rh positive (Rh+ve) and those in whom this antigen is absent are called Rh negative (Rh-ve).
- An Rh-ve person, if exposed to Rh+ve blood, will form specific antibodies against the Rh antigens, and hence Rh group should also be matched before transfusions.
- A special case of Rh incompatibility has been observed between the Rh-ve blood of a pregnant mother with Rh+ve blood of the foetus , which leads to a disease known as erythroblastosis foetalis.
- Rh antigens of the foetus do not get exposed to the Rh-ve blood of the mother in the first pregnancy as the two bloods are well separated by the placenta, during the delivery of the first child, maternal blood may get exposed to small amounts of the Rh+ve blood from the foetus and the mother starts preparing antibodies against Rh in her blood.
- In case of subsequent pregnancies, the Rh antibodies from the mother (Rh-ve) can leak into the blood of the foetus (Rh+ve) and destroy the foetal RBCs, which cause severe anaemia and jaundice to the baby leading to a condition known erythroblastosis foetalis.
- Erythroblastosis foetalis can be avoided by administering anti-Rh antibodies to the mother immediately after the delivery of the first child.
Posted by Neil Modi 5 years ago (10008913)
- 1 answers
Yogita Ingle 5 years ago (2577571)
- Blood coagulation or clotting is the mechanism to prevent excessive loss of blood from the body.
- Reddish brown scum formed at the site of a cut is due to clot formed mainly of a network of threads called fibrins in which dead and damaged formed elements of blood are trapped.
- Fibrins are formed by the conversion of inactive fibrinogens in the plasma by the enzyme thrombin.
- Thrombins are formed from another inactive substance present in the plasma called prothrombin by an enzyme complex known as thrombokinase.
- Calcium ions play a very important role in clotting.
Posted by Neil Modi 5 years ago (10008913)
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Yogita Ingle 5 years ago (2577571)
Blood is a fluid connective tissue that consists of plasma, blood cells and platelets. It circulates throughout our body delivering oxygen and nutrients to various cells and tissues. It makes up 8% of our body weight. An average adult possesses around 5-6 litres of blood.
Plasma
The liquid state of blood can be contributed to plasma as it makes up ~55% of blood. It is pale yellow in colour and when separated, it consists of salts, nutrients, water and enzymes. Blood plasma also contains important proteins and other components necessary for overall health. Hence, blood plasma transfusions are given to patients with liver failure and life-threatening injuries.
Red Blood Cells (RBC)
Red blood cells consist of Haemoglobin, a protein. They are produced by the bone marrow to primarily carry oxygen to the body and carbon dioxide away from it.
White Blood Cells (WBC)
White blood cells are responsible for fighting foreign pathogens (such as bacteria, viruses, fungi) that enter our body. They circulate throughout our body and originate from the bone marrow.
Platelets
Tiny disc-shaped cells that help regulate blood flow when any part of the body is damaged, thereby aiding in fast recovery through clotting of blood.
Posted by Shailesh Mahto 5 years ago (9965800)
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Posted by Komal Meena 5 years ago (9421619)
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Yogita Ingle 5 years ago (2577571)
The major functions of urban areas are trades and commerce, transport and communication, mining and manuf acturing, defence, administration, cultural and recreational activities.
Posted by Azad Saifi 5 years ago (8764276)
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Yogita Ingle 5 years ago (2577571)
Buddha tried two basic ways to spread his message to the people:
- He used Prakrit since it was a language of the common people so he could spread his message to large no. of people.
- He gave the message to think proactively instead of following him blindly.
Posted by Aarya Kumar 5 years ago (9898353)
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Balaji P 4 years, 11 months ago (10347755)
Posted by Nido Yami 5 years ago (10356179)
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Pushpendra Kumar2002 4 years, 9 months ago (10842869)
Posted by Neha Drnl 5 years ago (10356152)
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Khushi Soni 5 years ago (10353064)
Posted by Akash Kedia 4 years, 6 months ago (9929953)
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Sia ? 4 years, 6 months ago (6945213)
Posted by Shilpi Gupta 4 years, 6 months ago (8195768)
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Sia ? 4 years, 6 months ago (6945213)
The Virashaiva movement began in Karnataka in the mid-twelfth century. It was initiated by Basavanna and his companions like Allama Prabhu and Akkamahadevi. This movement strongly argued for the equality of all human beings, It was against Brahmanical ideas about caste and the treatment of women.
Posted by Nitesh Nick 5 years ago (8223169)
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Yogita Ingle 5 years ago (2577571)
प्रबंध के क्षेत्र में प्रभावी प्रबंध तथा इसकी सफलता हेतु कुछ मान्यताओं के आधार पर कार्य किये जाते हैं, जिन्हें प्रबंध के मार्गदर्शक कहते हैं। प्रबंध हेतु बनाये गये ये मार्गदर्शक ही प्रबंध के सिद्धांत हैं।
Posted by Nitesh Nick 5 years ago (8223169)
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Posted by Harshit Das 5 years ago (7870863)
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Posted by Gcm Tamizhan 5 years ago (10355929)
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Hariom Singh 5 years ago (10357282)
Posted by Ojal Gupta 5 years ago (9256117)
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Srikar B 4 years, 11 months ago (10148875)
Yogita Ingle 5 years ago (2577571)
| Sl. No. | Differentiating Property | Resistance | Resistivity |
| 1 | Definition | Resistance is the physical property of a substance because of which it opposes the flow of current i.e. electrons. | Resistivity is the physical property of a particular substance which is having particular dimensions. |
| 2 | Proportionality | Resistance is directly proportional to the length and temperature while it is inversely proportional to the cross-sectional area of the material. | Resistivity is only proportional to the nature and temperature of the particular material. |
| 3 | Symbol | R | ρ |
| 4 | Formula | R = V/I or, R = ρ(L/A)V = Voltage, I = Current, ρ = Resistivity |
ρ = (R×A)/L
R = Resistance, L= Length, A = Cross-sectional area |
| 5 | SI Units | The SI unit of resistance is Ohms | The SI unit of resistivity is Ohms-meter. |
| 6 | Applications | The property of resistance is used in several places like heaters, fuses, sensors, etc. | Electrical resistivity measurement is used as a quality control test for calcareous soil. |
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Yogita Ingle 5 years ago (2577571)
The heart performs the following important functions:
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