Unit 1: Chapter 32

Question 1

Kidney

Answer 1

Sheated in fibrous external capsule, surrounded by a mass of fatty connective tissue
Paired shaped organs. 8-18 lobes, composed of nephrons.
Weights: 113-170 grams
Lie outside the peritoneal cavity in the posterior upper abdomen

Question 2

Kidney location

Answer 2

Lies on each side of the vertebral columbine at the level of the 12th thoracic to 3rd lumbar vertebrae
Right kidney is lower due to the position of the kidney

Question 3

Hilus

Answer 3

Deep fissure where blood vessels and nerves enter and leave the kidney

Question 4

Ureters

Answer 4

Connects the kidney to the bladder also enters the kidney at the hilus

Question 5

Nephrons

Answer 5

Functional units of the kidney
Each has a glomerulus that filters blood and tubular structures that reabsorbed needed substance back onto blood.
Secretes unneeded substances that becomes urine

Question 6

Outer Cortex

Answer 6

Reddnish brown
Contains the glomeruli and convoluted tubules of neurons and blood vessels

Question 7

Inner Medulla

Answer 7

Light colored con shaped masses
Consits of renal pyramids
Divided by the columns of the cortex

Question 8

Renal Pyramid

Answer 8

Forms the lobes of the kidney

Question 9

Papillae

Answer 9

Formed by the apices of the pyramids
Perforated by the openings of the collecting ducts

Question 10

Renal Pelvis

Answer 10

Wide funnel shaped structure at the upper end of ureter.
Made up of calyces or cuplike structures that drain the upper and lower halves of the kidney.

Question 11

Adipose Tissue

Answer 11

Protects the kidneys from mechanical blows and assist the attached blood vessels and fascia to secure the kidney in place

Question 12

Urine Formation
2 processes

Answer 12

1. The filtration of blood through the globe runs to form an ultrafiltration of urine
2. The tubular reabsorption of electrolytes and nutrients needed to maintain the constancy of the internal enviroment while eliminating waste materials.

Question 13

Glomerular Filtration

Answer 13

Urine begins with the filtration of protein free plasma through the glomerular capilarries into the bowman’s capsule.
125 mL of filtrate is formed each minute or GFR (glomerular filtration rate)
Average: adult 125 mL/min or 180 L/day

Question 14

Capillary hydrostatic pressure

Answer 14

Filtration pressure

Question 15

Capilarry Colloidal Osmotic pressure

Answer 15

Reabsorption pressure

Question 16

Glomerular Capillaries Fluid Movement

Answer 16

Determined by the same factors that facilitate fluid movement in all capillaries beds
CHP, CCOP, CP

Question 17

Glomerular Filtrate Composition

Answer 17

Similar to plasma
Contains no proteins because large molecules do not readily cross the glomerular wall

Question 18

GFR

Answer 18

Pressure 60 mm Hg
2-3 times higher than that of other cap beds
Regulated by the constriction and relaxation of the afferent and efferent arterioles

Question 19

Efferent Arterioles

Answer 19

Constriction increases resistant to outflow from the glomeruli and increases pressure and the GFR
Innervated by the SNS and are sentive to vascomotive hormones: angiotensin II

Question 20

Afferent Arterioles

Answer 20

Constriction causes a reduction int he renal blood flow, glomerular filtration pressure and GFR.

Innervated by the SNS and are sentive to vascomotive hormones: angiotensin II

Question 21

ADH

Answer 21

Assists in maintenance of the extracellular fluid volume by controlling permeability of the medullary collecting tubules
Binds to receptors on the basolateral side of the tubular cells. This causes the aquaoprin-2 channels to move onto the luminal side of the turbulence producing a increase in water permeability.

Question 22

Tubular Reabsorption and Secretion

Answer 22

The glomerular filtrate moves from the bowman capsule into the tubular segment of the nephron.
While moving the filtrate is changed by the tubular transport of water and solutes.

Question 23

Tubular Transport

Answer 23

Can result in reabsorption of substances from the tubular filtrate into the peritubular capillaries or the secretion of substances from the pertitubular capillaries onto the tubular filtrate

Question 24

Passively Absorbed Substances Across Tubular Epithelial Cells

Answer 24

Water and urea along the concentration gradient

Question 25

Primary or Secondary Active Transport Across the Tubular Epithelial Cells

Answer 25

Na, K, CL, Ca, phosphate, irate, glucose and amino across are reabsorbed into he blood

Question 26

Average Output of Urine

Answer 26

60 ml/hour 1 mL of 125 mL glomerular filtrate is excreted in rejoin the other 124 mL is reabsorbed into the tubules .

Question 27

Basolateral Membrane

Answer 27

1 of 2 renal tubules cells membranes Substances pass and are reabsorbed from the tubular fluid Outside adjacent to interstitial fluid

Question 28

Luminal Membrane

Answer 28

1 of 2 renal tubules cells membranes Substances pass and are reabsorbed from the tubular fluid In contact with the tubular lumen and the tubular filtrate Substances move along concentration gradient but require facilitated or active transport to move across the basolater membrane into the interstitial fluid where the substance are absorbed into the peritubular capillaries.

Question 29

Cotransport (secondary active transport)

Answer 29

The bulk of energy used by the kidney support active transport that facilitate Na reabsorption with cotransport of substance such as glistening and amino acids Dependent on ATPase pumps on the basolateral side

Question 30

ATPase Pu,p

Answer 30

Maintains a low intracellular Na concentration that facilitates the downhill movement of Na from the filtrate across the luminal membrane.

Question 31

Proximal Tubule

Answer 31

Higly permeable to water Where 65% of all reabsorption and secondary process of the tubular system take place. Glucose, amino acids, lactate and water soluble vitamins are completely reabsorbed. Na, K, CL, HCO3 are 65-80 % reabsorbed.

Question 32

Transport Maximum

Answer 32

The maximum amount is substances that transport systems can reabsorbed per unit in time. Related to the number of carrier proteins that are amiable for transport

Question 33

Renal Threshold

Answer 33

Plasma level at thick the substance appears in urine

Question 34

Loop of Henle

Answer 34

Reabosorbs more Na and CL than water Plays important role in controlling the concentration of urine. Establishes a high concentration of osmotically active particles in the interstitium surrounding the medullary collecting tubules where the ADH hormone exerts its effects.

Question 35

Thin descending Segment of Loop of Henle

Answer 35

Highly permeable to water in equal proportions As urine filtrate moves down the move ther moves out of the filtrate into the surrounding interstitium Causing the osmolarity of the filtrate to reach its highest point at the elbow.

Question 36

Ascending Limb of Loop of Henle

Answer 36

Also called diluting segment Impermeable to water Solutes are reabsorbed but water can’t follow and remains the the filtrate as a result the filtrate become more and more dilute. Reaches osmolarity of 100 most/kg of water.

Question 37

Thick Segment of Loop of Henle

Answer 37

Thick epithelial cells Impermeable to water Contains Na/K/2Cl cotrasnport system 20-25% of literates load of Na, K, Cl is reabsorbed Site of action for loop diuretic

Question 38

Kidney and Osmolality

Answer 38

Kidney responds to chanted in osmolarity of extracellular fluid by producing wither concentrated or disturbed urine Completed by establishment of high concentration of osmotically active particulars int he interstitiune of the kidney medulla or the action of ADH.

Question 39

Countercurrent

Answer 39

Refers to flow of fluids in the opposite directions in adjacent structures

Question 40

How the Kidney Concentrates Urine

Answer 40

Osmolarity of bloody fluids relies on the ability of the kieny to produce diluted or concentrated urine by 3 factors 1. Osmolarity of interstitium fluids in the urine concentrating part of the kidney 2. ADH 3. Action of ADH on cells int he collecting tubules

Question 41

Osmolarity of Urine Concentration

Answer 41

1/5 of juxtamedullary nephrons, the loop pf Henle and hairpin shaped capillaries called vasa Reta descend into the mild array portion of the kidney to form a countercurrent system This system increased osmolarity promoting exhange of solutes where ADH mediated reabsorption of water takes place

Question 42

ADH and Concentration of Urine

Answer 42

Regulates the ability of the kidneys to concentrates urine Sybntesized by neurons in the hypothalamus and transported down they axon by the posterior pituary gland and released into circulation Stimulation is caused by increase in serum osmolarity

Question 43

Angiotensin II

Answer 43

Produce vasoconstriction of renal vessels Increased Na reabsortion indirecely by simulating aldosterone secretion fromt he adrenal glands and directly by increasing Na reabodption by the proximal tubules cells

Question 44

Renin

Answer 44

Functions by means of angiotensin II to produce vascocontrtion of the effect arterioles to prevent large decrease in GFR.

Question 45

Regulation of pH

Answer 45

Kidneys regulate body pH by conserving HCO3- and eliminating H+. Most H+ is excreted in urine because of tubular secretion mechanisms. Depends on the urine buffers: HCO3-, phosphate and ammonia.

Question 46

Urine

Answer 46

Clea, amber colored fluid Aprox 95% water and 5% dissolved solids Kidney produce 1.5 L/Day Contains metabolic wasters, few or no plasma proteins, blood cells or glucose molecules.

Question 47

Urine Test

Answer 47

Freshly voided specimen is most reliable

Question 48

Blood Chemistry

Answer 48

Blood tests can provide valuable information about the kinetics ability to remove metabolic wastes and maintain normal electrolytes and pH commotion of the blood.

Question 49

Radiological Studies

Answer 49

Can be used to detemined the size, shape and postion of the kidneys, pelvis and ureters

Question 50

Mesangial Cells

Answer 50

Lie between the capilarry tufts, provide support for the glomerulus in these areas Provide an intercellular substance similar to that of the basement membrane. Covers endothelial cells where they are not covered by basement membrane.

Question 51

Mesangial Cell Processes

Answer 51

Possess phagocytic properties and remove macromolecules that enter the intercapillary spaces. Also exhibit contractile properties in response to neurohumoral substances and are thought to contribute to the regulation of blood flow through the glomerulus.