INTRODUCTION
Maintaining a stable internal environment, or homeostasis, is essential for the survival of complex animals. Living organisms must maintain a salt and water balance, and they must continually remove the toxic by-products generated by metabolism. Organisms have evolved a variety of strategies to maintain a more or less stable internal environment. In animals that have a circulatory system, the blood typically passes through excretory organs, commonly termed kidneys. In terrestrial animals, the kidneys not only play a major role in the removal of wastes, but are also the primary organs of osmoregulation. Kidneys are paired, bean-shaped structures which are present at the lumber region along the two sides of the vertebral column and are retroperitoneal in nature. Kidneys are covered over by a fibrous connective tissue capsule and are kept in position by renal fascia. Mammalian kidneys are metanephric in origin. Structural and functional units are known as nephrons, and there are one million in number per kidney. Kidneys receive blood through the renal artery, and the blood leaves the kidney through the renal vein. The blood entering the kidneys undergoes pressure filtration, ultra-filtration and reabsorption, leading to the formation of urine. Kidneys regulate internal homeostasis by regulating the fluid and electrolyte balance in the body. The major functions performed by the kidneys are filtration of blood, formation of urine, removal of non-gaseous N2 wastes in the form of urea, uric acid, and ammonia, regulation of fluid volume, and regulation of fluid and electrolyte volume leading to regulation of blood volume and blood pressure.
OBJECTIVES
• Study of anatomical regions of mammalian kidney (sheep kidney)
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... This pressure leads to filtration under pressure, which is known as ultra filtration. This filtration leads to filtration of the blood into blood filtrate and nephric filtrate. Larger diameter will allow the reduction in the pressure exerted by the blood on the renal blood vessels, leading to the proper filtration.
Q.2
a) With the rise in ADH concentration, the permeability of the collecting tubules to water
b) Retention of water leads to a rise in fluid volume and a corresponding rise in blood volume
c) Urine will be highly concentrated due to increased reabsorption of water
Q.3 In the following states, the secretion of the ADH will increase in the blood:
Reduction in fluid volume in the body
Decrease in the blood pressure of the body
When the person drinks less water
Hypovolemia, that is, the reduction in the fluid volume of the body
A. High blood pressure, also called hypertension, occurs when the force of blood pushing against the walls of the blood vessels as
In this experiment, we determined the isotonic and hemolytic molar concentrations of non-penetrating moles for sheep red blood cells and measured the absorbance levels from each concentration. The results concluded that as the concentration increased the absorbance reading increased as well. A higher absorbance signifies higher amounts of intact RBCs. The isotonic molar concentration for NaCl and glucose is 0.3 M. The hemolysis molar concentration for NaCl and glucose is 0.05 M. Adding red blood cells to an isotonic solution, there will be no isotonic pressure and no net movement. The isotonic solution leaves the red blood cells intact. RBC contain hemoglobin which absorbs light, hemoglobin falls to the bottom of the tube and no light is absorbed. Determining the isotonic concentration of NaCl and glucose by finding the lowest molar concentration. In contrast to isotonic molar concentration, hemolysis can be determined by finding the
-The cells in the body will increase because osmosis causes molecules to move from a less concentrated solution to a more concentrated solution.
a) Urinalysis with significantly increased amounts of blood (via dipstick and sediment), protein, and leukocytes as well as slightly increased bilirubin and slightly decreased pH;
In this experiment the effects of blood vessel radius and blood pressure on glomerular filtration was experimented. The effect of decreasing the afferent arteriole radius on glomerular capillary pressure and filtration rate is as the glomerular capillary pressure decreased; the filtration rate decreased. The effect of increasing the afferent arteriole radius on glomerular capillary pressure and filtration rate is as the glomerular capillary pressure increased; the filtration rate increased. The effect of decreasing the afferent arteriole radius on glomerular capillary pressure and filtration rate is as the glomerular capillary pressure increased; the filtration rate increased. The effect of increasing the afferent arteriole radius on glomerular capillary pressure and filtration rate is that glomerular capillary pressure and filtration rate decreased
Fluid from the intravascular space shifts into the interstitial space surrounding the cells. This shift is caused by increased hydrostatic pressure within capillaries as the result of reduced liver function blocking blood flow. Increased capillary permeability from inflammation pushes albumin into the interstitial space, increasing interstitial osmotic pressure and deceasing capillary osmotic pressure. Due to decreased liver function, albumin is not longer readily made decreasing its presence in body. Without albumin, osmotic pressure will remain decreased within the plasma. As the body compensates for this loss of water and increased sodium in the intravascular space hypertonic alterations pull water from the intracellular fluid causing
results in the need for more blood. Since more blood is needed to fill the
The kidneys are bean shaped organs. They are a brownish-purplish sort of color. The outside of the kidneys are very tough, but smooth. This is described as a fibrous tunic. The outer part has millions of nephrons which are the basic unit of the kidney. The kidney is divided into two layers. The outer cortex and the medulla. When the outer cortex is stripped off you then get the medulla. The inside you have a thick mesh of muscular fibers. This is also smooth, and very even. It is very red in color, unlike the outside which is of brownish-purplish coloring. It is more red in color because it has tiny blood vessels. The kidneys are located in the posterior part of the abdomen, on both sides of the vertebral column. An easier way to say that would be right below the ribs towards the middle of your back. The right kidney is usually lower in location than the left kidney because of where the liver is. Each kidney is about 11cm long, 6cm wide, and 2.5 cm thick. The kidneys remove urea from the blood through a blood filtering unit called a nephron. There are more than 2 million nephrons in each kidney. The nephron is part of the homeostatic mechanism of your body. That mechanism maintains your water-salt balance, and it also regulates the amount of urea in your body. The blood enters the kidney through the bowmans capsule under pressure. This just surrounds the tuft of capillaries which is the glomerulus. The liquid just flows through the glomerulus under pressure. The pressure pushes the liquid out and keeps in the larger cells. This is filtration, because the glomerulus is taking the nutrients in and getting rid of the waste. After the filtering ...
Blood is filtered in the glomerulus and then water and waste is passed out as urine. (Edith Cowan University, 2001-2004)
Healthy kidneys clean the blood by filtering out extra water and wastes. They also make hormones that keep your bones strong and blood healthy. When both of your kidneys fail, your body holds fluid. Your blood pressure rises. Harmful wastes build up in your body. Your body doesn't make enough red blood cells. When this happens, you need treatment to replace the work of your failed kidneys.
the gain or loss of water when samples of the tissue are placed in a
π is equal to the osmotic pressure, V is equal to the cell volume and B is the intracellular solids (Hall). Ponder’s R value is the ratio of intracellular solvent volume to the water in its environment; R=(Vi -b)/W. These two equations are related because Ponder’s R value is a measure of how much of an osmometer a cell is while the van’t Hoff relation shows what the osmotic pressure is, both inside and outside the cell. Overall cell membrane permeability can be measured by Ponder’s R value while the osmotic pressure differentials between the external environment and the internal environment are seen with the van’t Hoff relation (Hall). Cells evolved to become great osmometers, but not perfect osmometers, in order to provide a way for solutes to move along permeable membranes. The van’t Hoff relation permits organisms to live in environments of varying osmolarity because regulating solute concentration within a cell can increase or decrease the cell’s affinity for osmosis (Darnell et al). Ponder’s R value, on the other hand, shows how a cell can never become a perfect osmometer. If a cell could become a perfect osmometer, it could cause cell lysis or shrinkage of the cell (Hall). The avoidance of perfect osmometry can be seen within the human erythrocyte as a small portion of cell water will not take part in an osmotic exchange due to tonicity within its
This is when osmatic pressure comes and plays a key role in the movement of water across a membrane from an area of low concentration to an area of higher concentration (p. 179). The osmatic pressure also helps with our sodium and potassium pumps found throughout the body. This helps maintain electrolyte concentration of the intracellular and extracellular fluids (p. 179). For the intake of water the main organ responsible would go to the hypothalamus found in the brain, it detects the pressure and allows the body to begin the process of thirst (p. 181). For excretion responsibilities we look at two hormones, Antidiuretic (water retention) and Aldosterone (sodium retention). In the same moments we can maintain balances, imbalances can also occur. Syndrome of Inappropriate Antidiuretics occurs when ADH does not decrease in response to low serum osmolality causing fluid overload (p. 181). Another type is Diabetes Insipidus which occurs from a deficiency of ADH and excess loss of water during urination (p. 181). A patient’s daily weight gain and lose can tell you about the fluid status throughout the
B. i ask that you should think about these precautions and take them into thought