Rider Urinary System

A&P II – Test 3 – Rider

Urinary System:
Q 1. a) What are the different parts of urinary system. The 2 kidneys, The 2 ureters, the Urinary Bladder and the Urethra. b) What is nephron? Name different parts of a nephron. Write absorption and secretion of different parts of a nephron. Nephron: It is the functional part of the kidney, encharged of filtration of blood and eliminates the nitrogenous waste of our bodies. The nephron consists of: functional units; two parts: renal corpuscle (with a two-layerd glomerular capsule that encloses it. They are separated by filtrate collecting capsular space) & renal tubule (Duct that leads away from the glomerular capsule and ends at the tip of the medullary pyramid). The renal tubule
is composed by: the Proximal Convulated Tubule, Descending part of the loop of Henle, the nephron loop of Henle, ascending pat of the loop of Henle, the distal convulated tubule and the collecting duct. Tubular Reabsorption: Removes useful solutes from the filtrate and returns them into the blood. The PCT reabsorbs 65% of glomerular Filtrate to the peritubular capillaries. It reabsorbs a greater variety of chemicals than other parts of the nephron. There are two routs for the PCT reabsorption: Transcelluar (through epithelial cells of PCT) and Paracellular (between epithelial cells of PCT). Tubular Secretion: Removes additional wastes from the blood and adds them to the filtrate. Wastes are the urea, uric acid, bile salts, ammonia, catecholamines and many drugs. By secreting hydrogen and bicarbonate ions there is a regulation that occurs of the bodies pH and fluids. c) What is glomerular filtrate? Write flow of glomerular filtrate. It is a special case of the capillary fluid exchange in which water and some solutes in the blood plasma pass from capillaries of the glomerulus into the capsular space of the nephron. To do so, fluid passes through three barriers that constitute a filtration membrane: The fenestrated endothelium of the capillary (these are highly permeable, although their pores are small enough to exclude blood cells from the filtrate)  The Basement Membrane ( Few particles may penetrate the small spaces but most of them would be held back)  Filtration slits (allows particles of less than 3nm to pass). So it goes through three barriers that leave particles behind depending on their size. Flow of the Glomerular filtrate: glomerular capsule  PCT  nephron loop  DCT  collecting duct  papillary duct  minor calyx  major calyx  renal pelvis  ureter  urinary bladder  urethra

D) What are the nitrogenous wastes of the body? (Lecture Note P 1). Define azotemia, uremia, polyuria, oliguria, anuria, glycosuria, proteinuria, hematuria. (Lecture Note P 1, 7 and Text Page P 905, 919)
Urea (proteins  amino acids  NH2 removed  forms ammonia, liver converts it to urea.
-Uric Acid – Nucleic Catabolism
-Creatinine – creatine phosphate catabolism.
-Azotemia: Abnormally high BUN (Blood Urea Nitrogen).
-Uremia: Toxic effects as wastes accumulate.
- Polyuria: production of abnormally large volumes of dilute urine.
-Oliguria: the production of abnormally small amounts of urine.
- Anuria: failure of the kidneys to produce urine.
- Glycosuria: a condition characterized by an excess of sugar in the urine, typically associated with diabetes or kidney disease.
-Proteinuria: the presence of abnormal quantities of protein in the urine, which may indicate damage to the kidneys.
-Hematuria: Hemoglobin in the urine.

Water, Electrolyte and Acid-Base Balance: Q 2. A) What are the fluid compartments of the body. How fluid move from one compartment to another?
65% is located in the Intra Cellular Fluid (ICF)
35% is part of the Extra Cellular Fluid (ECF). Out of the 35% in the ECF; 25% is tissue fluid; 8% is blood plasma, lymph and 2% transcellular fluid (including, CSF, synovial, peritoneal, pleural, among others).
Water moves by osmosis from the digestive tract to the bloodstream and by capillary filtration from the blood to the tissue fluid. b) What are the different forms of water gain and water loss in the body?. What are the disorders of water balance.
Metabolic Water: It is the product of aerobic metabolism and dehydration synthesis. About 200ml/day.
Preformed Water: Ingested in foods and drinks every day. About 1,600ml/day. c) Name major cations and anions of the body? What is the most abundant electrolyte (cations) in the ECF(Extra Cellular Fluid) and ICF (Intra Cellular Fluid)? What is the most abundant anions in the ECF and
ICF. Major Cations: Na+ , K+ , Ca2+, H+. Major Anions: Cl- ; HCO3- ; PO43-
The most abundant cation electrolytes are: Na+ in the ECF. And K in the ICF.
The most abundant anion is: Cl in the ECF and PO43 in the ICF

d) Name common disorders of acid-base balances.
Respiratory acidosis
Respiratory alkalosis (hyperventilation)
Metabolic acidosis
Metabolic alkalosis (rare)

Digestive System:

Q 3. a) What are the different parts of alimentary tract (Gastro Intestinal tract)?
What are the accessory organs of digestion?
Mouth, pharynx, esophagus, stomach, small intestine and large intestine.
- Accesory organs of the digestive system: teeth, tongue, liver, gallbladder, pancreas, salivary glands

b) What are the two important movements of small intestine? Write in brief digestion and absorption of carbohydrate, protein and fat in the body. (Lecture Note P 12 and Text Page 987) segmentation random ringlike constrictions mix & churn contents
12 times per minute in duodenum peristaltic waves begin in duodenum but each one moves further down push chyme along for 2 hours suppressed by refilling of stomach

Carbohydrate Digestion in Small Intestine
Salivary amylase stops working in acidic stomach  50% of dietary starch digested before it reaches small intestine
Pancreatic amylase completes first step in 10 minutes
Brush border enzymes act upon oligosaccharides, maltose, sucrose, lactose & fructose  lactose indigestible after age 4 in most humans (lack of lactase).
Carbohydrate Absorption
Sodium-glucose transport proteins (SGLT) in membrane help absorb glucose & galactose
Fructose absorbed by facilitated diffusion then converted to glucose inside the cell

Protein Digestion & Absorption
Pepsin has optimal pH of 1.5 to 3.5 -- inactivated when passes into duodenum & mixes with alkaline pancreatic juice (pH 8)
Pancreatic enzymes take over protein digestion by hydrolyzing polypeptides into shorter oligopeptides
Brush border enzymes finish the task producing amino acids that are absorbed into the intestinal epithelial cells amino acid cotransporters move into epithelial cells & facilitated diffusion moves amino acids out into the blood stream
Infants absorb proteins by pinocytosis (maternal IgA)

Fat Digestion: `
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Most fat digestion occurs in the small intestion through the action of pancreatic lipase. Fat is broken up into smaller emulsification droplets by certain components of the bile. The agitation produced by the intestinal segmentation breaks up fat into droplets and a coating of lecithin and bile keeps it broken up.
End product: Fatty acids and Glycerol (free fatty acid and mono-glycerol).
Fat Absorption:
The absorption of fats – and other lipids – depend on droplets in the bile called micelles.
Bile phospholipids and cholesterol diffuse into the center of the micelle to from its core. Micelles then pass down the bile duct into the duodenum, where they absorb fat-soluble vitamins, more cholesterol and the Free Fatty Acids and Monoglycerides produced by fat digestion.
The Micelles are reused, picking up other cargo of lipids and ferrying them to the enterocytes. Without micelles, the small intestine absorbs only about 40% to 50% of the dietary fat and almost no cholesterol.