Answer: Option D. -> All of the above
:
D
The fluid between our joints and surrounding our hearts and lungshelps them move without rubbing against each other and causing irritation and damage. Water has a large heat capacity which helps limit changes in body temperature in a warm or a cold environment. Water allows the body to release heat when ambient temperature is higher than body temperature. The body begins to sweat and due to the evaporation of water from the skin surface, it very efficiently cools the body.The ability of water to disassemble and rearrange other molecules isessential to the chemistry of life. It does this by forming weak bonds with other molecules.

Answer: Option A. -> 1.Isovolumetric contraction   2.Mitral valve   3.Tricuspid valve  4. IsovolumetricRelaxation  5. Aortic valve   6. Pulmonary Valve
:
A
The most fundamental heart sounds are the first and second sounds, usually abbreviated as S₁ and S₂. S₁ is caused by closure of the mitral and tricuspid valves at the beginning of isovolumetric ventricular contraction S₁ is normally slightly split (~0.04 sec) because mitral valve closure precedes tricuspid valve closure; however, this very short time interval cannot normally be heard with the stethoscope and hence only a single sound is perceived. S₂ is caused by closure of the aortic and pulmonic valves at the beginning of isovolumetric ventricular relaxation

Answer: Option D. -> Thromboplastin, Prothrombin, Thrombin, Fibrinogen, Fibrin
:
D
When the blood vessels are damaged they attract platelets. The damaged endothelial cells express tissue factor. The tissue factor initiates a coagulation cascade.The end result of the cascade is the formation of an enzyme called prothrombinase.This prothrombinase cleaves prothrombin giving rise to thrombin.The platelets have specific thrombin receptors; the thrombin attaches to the platelets and forms a weak plate plug. Thrombin acts on fibrinogen in the plasma and cleaves it to form insoluble fibrin strands.The insoluble fibrin strands are then stabilized to form a clot by fibrin stabilizing factor which is also activated by thrombin.

Answer: Option D. -> Negative Chronotropic effect - Increases the force of contraction of heart
:
D
The cardiac centres are of two types: cardiovagal and the vasomotor. Baroreceptors are sensors located in the blood vessels of all vertebrate animals. They sense the blood pressure and relay the information to the brain, so that a proper blood pressure can be maintained. An inotropic action alters the force or energy of muscular contraction.Change in contractility or force of contraction of the heart is also known as a chronotropic effect. Positive chronotropes increase heart rate; negative chronotropes decrease heart rate.

Answer: Option A. -> Only vertebrates, annelids and cephalopods, have closed circulatory system.
:
A
All vertebrates, annelids like earthworms and cephalopods like octopi, have a closed circulatory system, with the complete separation of both systemic and pulmonary circuits. The rest of the animal world has an open circulatory system. Birds, like mammals, have a 4-chambered heart. Amphibians and reptiles have 3 chambers in their hearts.

Answer: Option A. -> thrombocytes
:
A
Thrombocytes - irregularly shaped, disk like cytoplasmic fragment of a megakaryocyte that is shed in the marrow sinus and subsequently found in the peripheral blood, where it functions in clotting at the place of injury. A platelet contains granules in its central part (granulomere) and, peripherally, clear protoplasm (hyalomere), but no nucleus, is about one third to one half the size of an erythrocyte, and contains no hemoglobin.

Answer: Option A. -> (i) Stroke volume, (ii) 72, (iii) 5,040, (iv) 5
:
A
Stroke volume is the amount of blood the left ventricle pumps out in one cardiac cycle. This is around 70 ml. Cardiac output is the volume of blood pumped out by each ventricle per minute. Now to get cardiac output,we have to multiply stroke volume with the normal heart rate of 72 beats/min and we get 5,040 ml/min. This means that in one minute, each ventricle of a normal heart pumps about 5 litres of blood.

Answer: Option C. -> Fibrinogen- transport minerals, lipids, hormones and vitamins.
:
C
Globulins have some enzymes, carrier proteins. Immunoglobulins are involved in attack and destruction of pathogens. Fibrinogen is the blood clotting agent.
Albumin maintains osmotic pressure in blood cells, transports molecules and also eliminates free radicals.

Answer: Option A. -> Lymphatic vessels and lymphoid organs
:
A
The Lymphatic system is made of three main components - the lymphatic vessels, lymph, andthe lymph nodes. The lymphatic system has multiple interrelated functions. It is responsible for the removal of interstitial fluid from tissues. It absorbs and transports fatty acids and fats as chylefrom the digestive system. It transports white blood cells to and from the lymph nodes into the blood.

Answer: Option D. -> The heart develops from the ectoderm.
:
D
The 3 germ layers - the ectoderm, the mesoderm, and the endoderm (endoderm) are in place at the end of gastrulation.
The Ectoderm gives rise to the central nervous system (the brain and spinal cord) etc.
The Mesoderm gives rise to connective tissue, cartilage, and bone; striated and smooth muscles and the heart walls etc.
The Endoderm gives rise to the tonsils, the thyroid gland, parathyroid glands, and thymus gland; the larynx, trachea, and lungs; the gastrointestinal tract, the urinary bladder etc.