Function of blood - class-VIII

Blood performs many important functions within the body. These functions include the supply of oxygen to tissues (bound to hemoglobin, which is carried in red cells), the supply of nutrients such as glucose, amino acids, and fatty acids (dissolved in the blood or bound to plasma proteins e.g., blood lipids), transport of gases etc.

Blood maintains water balance in the body by bringing constant exchange of water between circulating blood and tissue fluid. Regulating pH and transportation of excretory material are other functions performed by blood.

Blood Is an important fluid connective tissue which circulates throughout the body. It performs some very important functions like transport of oxygen from lungs to the cells, transport of food material, Transport of excretory material, Transport of other substances and Transport of cell wreckage. etc. 

Blood allows heat transfer of heat from deeper tissues to the surface of the body where it can be lost. Hormones are carried by blood from endocrine glands to place of use, Also glucose and other nutrients are transported from alimentary canal through blood to different cells in the body.

The main function of the cardiovascular system is, therefore, to maintain blood flow to all parts of the body, to allow it to survive. Veins deliver used blood from the body back to the heart. In the lungs, the blood picks up oxygen that we breathe in and gets rid of carbon dioxide, which we breathe out.

Blood transports the digested food from the alimentary canal to the tissue. Blood also distribute hormones secreted by the endocrine glands. The blood helps in keeping the temperature of the body uniform by distributing heat. Thus option C is the correct answer. 

Blood performs the important task of protecting the body from the infections and disease-causing bacteria. The white blood cells found in blood are responsible for safeguarding the different organs of the body by producing antibodies and proteins which are capable of fighting off and killing the germs and viruses that cause serious damage to the body cells. The platelets present in blood handle the task of limiting blood loss in the wake of an injury by helping the blood to clot quickly. 

Lymph has no RBCs but about 99% are lymphocytes usually of the small type, the remaining 1% is made up of leucocytes.

(b) Blood is colourless in insects. insects have tracheal respiration. It is carried on by an extensive system of inter-communicating tubes called trachea.

Normal fasting blood glucose is approximately 70-100 mg/dL. Converting this to grams per litre, 1 gram per litre equals 100 mg/dL, which is the standard reference.

The bicarbonate buffer system (HCO3-) is the primary mechanism for maintaining the pH balance in the blood of vertebrates, including birds.

Normal fasting blood glucose is 80-100 mg/100 ml (70-100 mg/dL is the modern standard range). Option A is too low (hypoglycemic range), option B has wrong units, and option D's upper limit is hyperglycemic.

The normal serum calcium level for healthy adults is typically between 8.5 and 10.5 mg/dL.

Red blood cells (erythrocytes) are significantly more numerous in human blood than white blood cells (leukocytes), which are present in much lower concentrations.

Haemocyanin is a copper-containing protein that transports oxygen in the blood of many molluscs and arthropods, giving the blood a blue color when oxygenated.

Urea is synthesized in the liver from ammonia and carbon dioxide. The urea synthesis is a five-step cyclic process, with five distinctive enzymes. This urea is released into the bloodstream from the liver cells. Through blood, urea is transported to kidneys where the blood is filtered and urea is passed out of the body in the urine. Hence the waste matters (urea) are transported by the blood.

Blood clotting factors are needed for blood to clot (coagulation). Prothrombin is one of the clotting factors made by the liver. During normal blood coagulation, a coagulation cascade activates prothrombin by converting it into the serine protease thrombin. Thrombin then converts the soluble fibrinogen into insoluble fibrin strands. These strands are then cross-linked by factor XIII to form a blood clot. As soon as blood from a wound is exposed to the air, the platelets disintegrate and react with fibrinogen to create fibrin: a mass of tiny threads. This triggers a whole series of reactions that rely on adequate levels of calcium and vitamin K to work. Calcium is also an important part of the blood clotting process. Elastin is a highly elastic protein in connective tissue and allows many tissues in the body to resume their shape after stretching or contracting. It is not present in the blood.

A person cannot expel all the air from the lungs even after forceful expiration. The volume of air which remains in the lungs after the most forceful expiration is called residual volume, it is about 1100 mL to 1200 mL A rise in $PCO _{2}$ decreases the $O _{2}$ affinity of haemoglobin.

The ability of the body to regulate its internal physiological processes in order to maintain the equilibrium is called the dynamic equilibrium. It is performed to keep the physiological responses from fluctuating with the external conditions of the environment. Different organ system work under the regulation of hypothalamus and medulla maintain the dynamic homeostasis. 

The amount of oxygen in the blood is 20.8ml or 20.8 volume. Oxygen is carried in the blood in two forms: dissolved and bound to hemoglobin. 

Blood is a fluid connective tissue. Blood is considered a connective tissue for two basic reasons:- 

Blood iѕ аlѕо a regulator оf mаnу factors in the body. It oversees the temperature оf the bоdу аnd maintains it tо a level that iѕ tolerated bу thе bоdу with ease. Blood iѕ аlѕо responsible fоr controlling thе concentration оf Hydrogen ions in thе body, whiсh аrе аlѕо knоwn аѕ pH balance. Thе administration оf thе levels оf water аnd salt required bу еасh cell оf thе bоdу аlѕо falls undеr thе regulation duties оf blood. An anоthеr regulatory task performed bу blood iѕ tо control thе blood pressure аnd restrict it undеr a nоrmаl range.

In the body, the heart is muscular organ made up of cardiac muscles which has four chambers. The right side of the heart receives deoxygenated blood from the veins and pumps it to the lungs that oxygenates it.The left side of the heart receives oxygenated blood from the lungs and pumps it through the arteries to all body. Thus the correct answer is option A.

Blood is the primary means of transport in the body as it is responsible for transporting important nutrients and materials to and from the cells and molecules that make up our body. It is the duty of blood to first take the oxygen processed by the lungs to all the cells of the body and then to collect the carbon dioxide from the cells and deliver it to the lungs. 

The blood helps to keep certain values of the body in balance. For instance, it makes sure that the right body temperature is maintained. This is done both through blood plasma, which can absorb or give off heat, as well as through the speed at which the blood is flowing. When the blood vessels expand, the blood flows more slowly and this causes heat to be lost. When the environmental temperature is low the blood vessels can contract, so that as little heat as possible is lost. Even the so-called pH value of the blood is kept at a level ideal for the body. The pH value tells us how acidic or alkaline a liquid is. A constant pH value is very important for bodily functions.