(d) Complete the following paragraph by filling in
the blanks (i) to (v) with appropriate words:
(i)
enter the blood through the
capillary walls. Many wastes and excess
bind with albumin or dissolve in
the plasma, which get transported to the liver
from the intestine. The
(iii) filters
wastes and other harmful substances from the
blood. It converts some wastes (amino acids)
into a compound called!
(iv
The blood
carries urea to the
(v)
for the excretion
in the form of urine.
Answers
Explanation:
Plasma, also called blood plasma, the liquid portion of blood. Plasma serves as a transport medium for delivering nutrients to the cells of the various organs of the body and for transporting waste products derived from cellular metabolism to the kidneys, liver, and lungs for excretion. It is also a transport system for blood cells, and it plays a critical role in maintaining normal blood pressure. Plasma helps to distribute heat throughout the body and to maintain homeostasis, or biological stability, including acid-base balance in the blood and body.
blood plasma
blood plasma
Blood sediment in test tubes, showing plasma (clear fluid), red blood cells (red), and the release of hemoglobin into the surr tambe
Plasma
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Edwin Joseph Cohn
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Plasma is derived when all the blood cells—red blood cells (erythrocytes), white blood cells (leukocytes), and platelets (thrombocytes)—are separated from whole blood. The remaining straw-coloured fluid is 90–92 percent water, but it contains critical solutes necessary for sustaining health and life. Important constituents include electrolytes such as sodium, potassium, chloride, bicarbonate, magnesium, and calcium. In addition, there are trace amounts of other substances, including amino acids, vitamins, organic acids, pigments, and enzymes. Hormones such as insulin, corticosteroids, and thyroxine are secreted into the blood by the endocrine system. Plasma concentrations of hormones must be carefully regulated for good health. Nitrogenous wastes (e.g., urea and creatinine) transported to the kidney for excretion increase markedly with renal failure.
blood diagram
blood diagram
Blood is made up of multiple components, including red blood cells, white blood cells, platelets, and plasma.
Encyclopædia Britannica, Inc.
blood diagram
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blood: Plasma
The liquid portion of the blood, the plasma, is a complex solution containing more than 90 percent water....
Learn how scientists used a fidget spinner to separate plasma from blood cells
Learn how scientists used a fidget spinner to separate plasma from blood cells
Researchers use a fidget spinner as a centrifuge to separate blood plasma.
© American Chemical Society (A Britannica Publishing Partner)
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Plasma contains 6–8 percent proteins. One critical group is the coagulation proteins and their inhibitors, synthesized primarily in the liver. When blood clotting is activated, fibrinogen circulating in the blood is converted to fibrin, which in turn helps to form a stable blood clot at the site of vascular disruption. Coagulation inhibitor proteins help to prevent abnormal coagulation (hypercoagulability) and to resolve clots after they are formed. When plasma is allowed to clot, fibrinogen converts to fibrin, trapping the cellular elements of blood. The resulting liquid, devoid of cells and fibrinogen, is called serum. Biochemical testing of plasma and serum is an important part of modern clinical diagnosis and treatment monitoring. High or low concentrations of glucose in the plasma or serum help to confirm serious disorders such as diabetes mellitus and hypoglycemia. Substances secreted into the plasma by cancers may indicate an occult malignancy; for instance, an increased concentration of prostate-specific antigen (PSA) in a middle-aged asymptomatic man may indicate undiagnosed prostate cancer.
Serum albumin, another protein synthesized by the liver, constitutes approximately 60 percent of all of the plasma proteins. It is very important in maintaining osmotic pressure in the blood vessels; it is also an important carrier protein for a number of substances, including hormones. Other proteins called alpha and beta globulins transport lipids such as cholesterol as well as steroid hormones, sugar, and iron.
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The gamma globulins, or immunoglobulins, are an important class of proteins that are secreted by B lymphocytes of the immune system. They include most of the body’s supply of protective antibodies produced in response to specific viral or bacterial antigens. Cytokines are proteins synthesized by cells of various organs and by cells found in the immune system and bone marrow in order to maintain normal blood cell formation (hematopoiesis) and regulate inflammation. For example, one cytokine called erythropoietin, synthesized by specialized kidney cells, stimulates bone marrow blood progenitor cells to produce red blood cells. Other cytokines stimulate the production of white blood cells and platelets. Another protein system in the plasma, called complement, is important in mediating appropriat