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A n P 2 > Urinary System > Flashcards

Urinary System Flashcards

1
Q

Metabolism

A

Metabolism - waste products (In excess = toxic)
Respiratory system: CO2, water
Digestive system: water, salts, CO2, metabolic wastes
Integumentary system: excretes H20, inorganic salts, lactate, urea
Urinary system: metabolic wastes, toxins, drugs, hormones, salts, H*, H20

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2
Q

6 organs

A

2 kidneys
2 ureter
Urinary bladder

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3
Q

Kidney functions

A

. Main function is the primary function is to filter blood plasma and separate waste from useful chemicals that our body needs return those beneficial substances back to the blood and eliminate metabolic wastes.

It can also regulate blood volume and blood pressure by eliminating or conserving water. So it controls water volume.

it also regulates Osmolarity. You can maintain osmolarity or the solute concentration of lecture. but it can maintain the osmlerity of what influence can control the balance of water and what solutes are eliminated. and it aims to achieve a consistent
Osmoority of somewhere around
300 million osmoles per liter

it also secretes the hormone EPO.
We’ve talked about that when we talked about the search through system. So every stimuli production of bread, blood cells, red blood cells, obviously more than oxygen transport

regulates the partial pressure of carbon dioxide and acid base balance.

Sunthesising hormones

Detoxification and clearance of hormones

Gluconeogenesis during starvation

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4
Q

Kidney- renal fascia

A

Renal fascia- just a layer similar to the fascia of a muscle. It’s a thin layer like elastic, connected tissue that encloses the kidney itself as well as the adrenal glands.
•Surrounds adipose tissue and helps anchor kidneys to abdominal wall

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5
Q

Kidney - renal capsule

A

which is a tough and fibrous layer. Main role is to protect the kidney from trauma or from infection.And inside that we have some adipose tissue that’s there for some cushioning

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6
Q

Kidney -hilum

A

Blood vessels and nerves all entering from one spot. main entrance and exit point of our kidney. So quite important when we think about kidneys function. It’s the place where arteries, nerves, veins and the ureter exit

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7
Q

Kidney- parenchyma

A

parenchyma refers to the functional tissue that carries out the filtration and reabsorption of substances. 🌟

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8
Q

parenchyma

A

2 major regions
1. Outer renal CORTEX
2 inner renal MEDULLA

Cortex- please where filtrations is going to occur. Place where nephrons located primarily

Medulla- inside the medulla you have the renal pyramids. within the pyramids we have collecting ducts that gather urine from the nephrons.
Renal columns project between pyramids

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9
Q

Kidney internal anatomy

A
  • Papilla = where all urine from the
    collecting tubules drain into the minor calyces

• Minor calyces - funnel-shaped chambers into which renal papillae extend

Funnel into Major calyces
Converge to form the renal pelvis (chamber) which is surrounded by the renal sinus
• Renal pelvis narrows into the ureter, which exits the kidney at the hilum and connects to the bladder

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10
Q

Nephron structure

A

• Is the histological and functional unit of the kidney

• Each kidney has about 1.2 million nephrons

The nephron is the basic structural unit of the kidney. It consists of a renal corpuscle, proximal convoluted tubule, loop of Henle, and distal convoluted tubule. Each nephron plays a vital role in filtering and regulating the composition of urine.

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11
Q

Renal corpuscle

A

Consists of a…
1. Bowman Capsule (double-walled chamber)
• Outer layer - parietal
• Inner layer - visceral

  1. Glomerulus (network of capillaries)
    • Unique characteristics that make it highly permeable
    • Fenestrae - openings
    • Filtration slits - gaps

• Vascular and Urinary poles
• Vascular:
• Afferent arteriole - supplies blood
• Efferent arteriole - drains blood
• Urinary pole, parietal wall turns away from the corpuscle resulting in the renal tubule

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12
Q

Renal tubule

A

A duct that leads away from the glomerular capsule and ends at the tip of the medullary pyramid

Divided into four (4) regions
1. Proximal convoluted tubule (PCT) - arises from glomerular capsule. it originates directly from the glomerular capsule, and it’s responsible for reabsorbing the majority filtrate components so when our blood makes its way into the glomerulus, it pushes, filtrate out into the proximal convoluted tubules . Some of that stuff that is pushed out we want to come back into our blood which is going to happen in the proximal area of the tubule

  1. Nephron loop (loop of Henle) - long U-shaped portion of renal tubule. Consist of descending and ascending limbs and well as thick and thin segments.
  2. Distal convoluted tubule (DCT) - begins shortly after the ascending limb renters the cortex
  3. Collecting duct - receives fluid from the DCTs of several nephrons as it passes back into the medulla
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13
Q

Renal circulation

A

Renal artery (largest) divides into segmental arteries that give rise to:
• Interlobar arteries: up renal columns, between pyramids
• Branch to arcuate arteries
• Branch to cortical radiate arteries
• Branch to afferent arterioles: each supplying one nephron
• Leads to a ball of capillaries = glomerulus

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14
Q

Circulation in cortex

A

In the cortex
• Peritubular capillaries branch off the efferent arterioles supplying the tissue near the glomerulus, the proximal and distal convoluted tubules
• Then flows, cortical radiate vein -› arcuate veins -› interlobular veins -› renal vein.
Renal vein exits hilum and drains into
inferior vena-cava

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15
Q

Circulation in medulla

A

In the medulla
•Efferent arterioles give rise to the vasa recta, supplying the nephron loop portion the nephron

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16
Q

How many major organs make up the urinary system?

A

6

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17
Q

What is the purpose of the Renal Fascia?

A

It surrounds adipose tissue and helps anchor the kidneys to abdominal wall.

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18
Q

Which part of the kidney is the outermost portion?

A

Renal Cortex
Cortex- outermost layer

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19
Q

What does the papilla primarily drain into?

A

Minor calyxes

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20
Q

What is the structure that the major calyxes converge to form?

A

Renal pelvis

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21
Q

Which pole of the glomular capsule connects to the rest of the nephr structure and leads to the collecting ducts for urine transport?

A

Urinary pole

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22
Q

Which segment of the renal tubule is the longest and most coiled?

A

Proximal convoluted tubule

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23
Q

Which artery is the largest one that delivers blood to the kidney?

A

Renal artery

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24
Q

How much blood volume, in terms of cardiac output, is directed towards the kidneys during rested states?

A

21%

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25
Q

The afferent arterioles in the kidney lead to a ball of capillaries known as:

A

Glomerulus

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26
Q

Urine products

A

Main function of nephrons and collecting ducts

Control the composition of body fluids/ remove waste from the blood= urine

Urine contains waste excess water and electrolytes

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27
Q

Urine is the final product of what processes

A

• Urine is the final product of the processes of:
1. Glomerular filtration
2. Tubular reabsorption
3. Tubular secretion
4. Water conservation

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28
Q

Fluid

A

• Fluid: capsular space = glomerular filtrate;
PCT & DCT =tubular fluid;
collecting duct = urine

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29
Q

Filtration membrane

A
  1. Glomerular filtration - special case of the capillary fluid exchange process in which water and some solutes in the blood plasma pass from the capillaries of the glomerulus into the capsular space of the nephron
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30
Q

Filtration membrane barriers

A

Filtration membrane three (3) barriers through which fluid passes
1. Fenestrated endothelium of glomerular capillaries
• 70 to 90 nm filtration pores exelude bleed cells

  1. Basement membrane
    •Negative charge, exeludes molecules greater than 8 m
    • Albumin repelled by negative charge
  2. Filtration slits
    • Podoeyte cell extensions wrap around the capillaries to form a barrier laver with
    30 nm filtration slits
    Negatively charged (obstacle for large anions)
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31
Q

What passes through the filtration membrane

A

Almost any molecule smaller than 3 nm can pass freely through the filtration membrane
- Water, electrolytes, glucose, fatty acids, amino acids, nitrogenous wastes, and vitamins
Some substances of low molecular weight are bound to the plasma proteins and cannot get
Through the membrane
- Most calcium, iron, and thyroid hormone

32
Q

Filtration pressure

A

Blood hydrostatic pressure (BHP)
• Higher in glomerular capillaries (60 mm Hg V’s 10 -15 in others)
•Because afferent arteriole is larger than efferent arteriole

Hydrostatic pressure in capsular space
• 18 mm Hg due to high filtration rate and continual accumulation of fluid in the capsule

Colloid osmotic pressure (COP) of blood
• About the same here as elsewhere: 32 mm Hg
• Glomerular filtrate is almost protein-free and has no significant COP

Higher outward pressure of 60 mm Hg, opposed by two inward pressures of 18 mm Hg and 32 mm Hg

Net filtration pressure : 60(out)-18(in)-32 (in) = 10 mmHg(out)

33
Q

Regulation of glomerular filtration

A

GFR control is achieved by three (3) homeostatic mechanisms:
Renal autoregulation
• The ability of the nephrons to adiust their own blood flow and GFR without external (nervous of hormonal) control
Sympathetie control
•Sympathetle NS and epinephrine constriet the arterioles in strenuous exercise or acute conditions (circulatory shock
Redirects blood from the kidneys to the heart, brain, and skeletal muscles
Hormonal control
•Renin secreted If BP drops dramatieally
• Renin converts angiotensinogen, (blood protein), into angiotensin 1
• In the lungs and kidneys, angiotensin converting enzyme (ACE) converts angiotensin I to angiotensin II (the active hormone)

34
Q

Glomerular filtration

A

Glomerular filtration
Creates a plasmalike filtrate of the blood

35
Q

Proximal convoluted tubule

A

PCT reabsorbs ~65% of glomerular filtrate + removes some substances from the blood and secretes them into the tubular fluid for disposal in urine
• Length + microvilli = large absorptive surface area
.The cells also contain numerous large mitochondria for active transport (~6% of daily calories).

Tubular reabsorption = reclaiming water and solutes from tubular fluid
and returning them to the blood (2 routes)
1.Transcellular route
Substances pass through the cytoplasm of the PCT epithelial cells and out their base
2.Paracellular route
•Substances pass between PCT cells
•Junctions between epithelial cells are quite leaky and allow significant amounts of water to pass through
•Solvent drag water carries with it a variety of dissolved solutes
• Taken up by peritubular capillaries

36
Q

Tubular reabsorption

A

Tubular Reabsorption
Sodium reabsorption:
• Creates an osmotic and electrical gradient that drives the reabsorption of water and other solutes
• Creates steep concentration gradient that favors diffusion into the epithelial cells

Two (2) types of transport proteins responsible for sodium uptake
1. Symports that bind Na* with another solute such as glucose, AA, or La
2. Na+-H+ antiport that pulls Na* into the cell while pumping out H* into tubular fluid.
Angiotensin II activates Na-H antiport, influencing Na+ reabsorption

Sodium is prevented from accumulating in the epithelial cells by Na-K pumps in the basal surface of the epithelium
• Pumps Na* out into the extracellular fluid
•Picked up by peritubular capillaries and returned to the bloodstream
• ATP consuming active pumps
• Chloride ions are negatively charged so they follow Na+

37
Q

Other chemicals

A

POtassium (co-transported with Na+), magnesium, ana phosphate ions diffuse through the paracell route with water.

Calcium:
• ~52% reabsorbed via para-vascular route and 14% by the transcellular route
• 33% reabsorbed later in the nephron under the influence of parathyroid hormone
• remaining 1% excreted in the urine

Glucose
• Co-transported with Na+ by symports (sodium-glucose transporters), removed from cell surf facilitated diffusion.

Nitrogenous wastes (Urea):
Peritubular capillary
• Passes through the epithelium with water.
• The nephron reabsorbs 40-60% of the urea in tubular fluid.
• Kidneys remove ~50% of the urea from the blood keeping its concentrations down to a safe level but not completely clearing it from the blood.

38
Q

Kidney filtration

A

Kidney reduce 180L of glomerular fates to 1-2 litres urine each day

Kidneys reduce 180 L of glomerular filtrate to 1 or 2 L urine each day
•Two-thirds of water in filtrate is reabsorbed by the PCT
•Reabsorption of all the salt and organic solutes makes the tubule cells and tissue fli hypertonic
•After water and solutes leave the basal surface of the tubular epithelium, they are reabsorbed by the peritubular capillaries
- Reabsorbed by osmosis and solvent drag

Three (3) factors promote osmosis into the capillaries
1. High interstitial fluid pressure that drives water into the capillaries
2. Narrowness of efferent arterioles lowers blood hydrostatic pressure (less resistance to absorption)
3. Proteins remain in blood after filtration, which elevates colloid osmotic pre
• High COP and low BHP in the capillaries and high BHP in the tissue fluid balance of forces in the peritubular capillaries favours reabsorption
• Accentuated with angiotensin |I

39
Q

Tubular secretion

A

Process in which renal tubule extracts chemicals from capillary blood and secretes them into tubular fluid

Two (2) purposes in PCT and nephron loop
1. Waste removal
• 60-67% of water, Nat, Cl-, K+, HCO3- and urea; 100% of glucose, amino acids,, lactic acid, and water-soluble vitamins, in addition to a variable amount of HPO, present in the filtrate also being reabsorbed.
•Clears blood of pollutants, morphine, penicillin, aspirin, and other drugs

  1. Acid-base balance
    - - Secretion of hydrogen and bicarbonate ions help regulate pH of body fluids
40
Q

Nephron loop

A

Primary function = generate osmotic gradient that enables
collecting duct to concentrate the urine and conserve water

Electrolyte reabsorption from filtrate
• Thick segment reabsorbs 25% of Na, K, and CI
• lons leave cells by active transport and diffusion
• NaCI remains in the tissue fluid of renal medulla
• Water cannot follow since thick segment is impermeable
• Tubular fluid very dilute as it enters distal convoluted tubule

41
Q

Distal convoluted tubule

A

Fluid in the DCT contains about 20% of the water and 7% of the salts from glomerular filtrate
• If this were all passed as urine, it would amount to 36 L/day

DCT and collecting duct reabsorb variable amounts of water salt and are regulated by several hormones
• Aldosterone
• Atrial natriuretic peptide
• ADH
• Parathyroid hormone

42
Q

Aldosterone

A

Salt-retaining hormone
• Steroid secreted by the adrenal cortex
• When blood Na* concentration fall or when K* rises
• When there is a drop in blood pressure

• Acts on thick segment of nephron loop, DCT, and cortical portion of collecting duct
•Stimulates the reabsorption of more Na* and secretion of K*
• H2O and CI- follow Na* = NaCI & H2O retained by body. Urine volume is reduced with elevated K*

43
Q

Atrial Natriuretic Peptide (ANP)

A

ANP is secreted by the atrial myocardium in response to high blood pressure

Four (4) actions result in the excretion of more salt and water in the urine, thus reducing blood volume and pressure
1. Dilates afferent arteriole, constricts efferent arteriole: increase GFR
2. Inhibits renin and aldosterone secretion
3. Inhibits secretion of ADH
4. Inhibits NaCI reabsorption by collecting duct

44
Q

Antidiuretic Hormone (ADH)

A

Secreted by posterior lobe of pituitary

In response to dehydration and rising blood osmolarity
• Stimulates hypothalamus

Make collecting duct more permeable to water
• Water in the tubular fluid renters the tissue fluid and bloodstream rather than being lost in urine

45
Q

Parathyroid hormone (PTH)

A

Secreted from parathyroid glands in response to calcium deficiency (hypocalcemia)
• Acts on PCT to increase phosphate excretion
• Acts on the thick segment of the ascending limb of the nephron look and on the DCT to increase calcium reabsorption
• Increases phosphate content and lowers calcium content in urine
• PTH stimulates calcitriol synthesis by epithelial cells of the PCT

46
Q

The collecting duct

A

Collecting duct begins in the cortex receives tubular fluid from the nephrons.
• Reabsorbs water and concentrates urine as passes through medulla.
• ~ 4x as concentrated at the end of
CD.
Two (2) factors
1. Osmolarity of the extracellular fluid (4x higher in the lower medulla than the cortex)
2. Medullary portion of CD more permeable to
water than solutes. As urine passes down CD water leaves (via osmosis), wastes remain in the tubule

47
Q

Control of water loss

A

Concentration depends on hydration
• If well hydrated the cortical portion of CD reabsorbs NaCI
• Impermeable to water = salt removed from urine but water re
• Produce large amounts of hypotonic urine

Dehydration = concentrated urine.
• Dehydration causes pituitary to release ADH
• Increases water reabsorption
• Reduces urine output

48
Q

Fluid compartments

A

65% intracellular fluid
35% extracellular fluid
25 % tissue fluid
8% blood plasma and lymphatic fluid
2% trancellular fluid

49
Q

Fluid compartments and osmosis

A

Fluid continually and easily exchanged between compartments via capillary walls and plasma membranes so osmotic gradients never last for very long
•If osmolarity of the tissue fluid rises, water moves out of the cell
• If it falls, water moves in

Osmosis determined by the relative concentrations of solutes in each compartment
• Electrolytes: most abundant solute particles
• Sodium salts in ECF
• Potassium salts in ICF

Electrolytes play the principal role in governing the body’s water distribution and total water content

50
Q

Regulation of fluid intake

A

Thirst governs fluid intake

Dehydration
• Reduces blood volume and blood pressure
• Increases blood osmolarity

Osmoreceptors in hypothalamus:
• Respond to angiotensin II produced when BP drops and to rise in osmolarity of CF with drop in blood volume
•Osmoreceptors communicate with the hypothalamus and cerebral corte
• Hypothalamus produces ADH
• Cerebral cortex produces conscious sense of thirst
• Intense sense of thirst with 2 - 3% increase in plasma osmolarity or
10 - 15% blood loss

51
Q

Regulation of output

A

Water output controlled by variations in urine volume.
Changes in urine volume linked to adjustments in sodium reabsorption ( as sodium is reabsorbsd or excreted water follows)
Concentrate the urine through action of ADH( ADH secretion stimulates by hypothalamic osmoreceptorz in response to dehydration

52
Q

Electrolyte balance

A

Physiological functions of electrolytes
• Chemically reactive and participate in metabolism
• Determine electrical potential across cell membranes
• Strongly affect osmolarity of body fluids
• Affect body’s water content and distribution

Major cations
• Sodium (Na), Potassium (K), Calcium (Ca?), Hydrogen (H)

Major anions
Chloride, bicarbonate and phosphate

53
Q

Sodium

A

Principal ions responsible for Resting Membrane Potential
• Na-K pump

Principal cation in ECF:
• Sodium salts account for 90 - 95% of osmolarity of ECF
•Most significant solute in determining total body water and distribution of water among the fluid compartments

Na* gradient a source of potential energy for cotransport of other solutes such as glucose, potassium, and calcium

NaHCO3 has major role in buffering pH in ECF

54
Q

Sodium

A

Adult needs about 0.5 g
of sodium per day

Sodium concentration coordinated by aldosterone - “salt-retaining hormone”
• Aldosterone receptors in ascending limb of nephron loop, the DCT, and cortical part of CD
• Little effect on urine & blood volume & BP

ADH: modifies water excretion independently of sodium excretion
• Increase = water retention
• Decrease = water excretion

Atrial natriuretic peptide
(ANP) and brain natriuretic peptide (BNP)
• Inhibit Na+ and water reabsorption, and the secretion of renin and
ADH
- Kidneys eliminate Na*
& H2O to lower BP

55
Q

Potassium

A

Produces (with Na+) the resting membrane potentials and action potentials
• Most abundant cation of IF
•Greatest determinant of intracellular osmolarity and cell volume

Na-K pump

Cofactor for PRO synthesis and other metabolic processes

K+ homeostasis is closely linked to that of Na+

90% of K* in glomerular filtrate is reabsorbed by the PCT

Hyperkalemia can have opposite effects depending on whether concentrations rise quickly or slowly.
• Sudden increase from ruptured cells (Crush injury) = cells abnormally excitable
•Slower onset e.g. renal failure = cells become less excitable
•Rare
•Symptoms: heavy sweating, vomiting or diarrhoea = muscle weakness
depressed reflexes and irregular heart activity

56
Q

Chloride

A

Required for the formation of stomach

Hydrochloric acid (HCI)

Most abundant anions in ECF

Major contribution to CF osmolarity

Chloride shift that accompanies CO, loading and unloading in RBCs

Major role in regulating body pH
•Primary homeostasis achieved as an effect of
Na homeostasis
•As Na* is retained, chloride ions passively follow

57
Q

Calcium

A

• Lends strength to the skeleton
• Activates sliding filament mechanism of muscle contraction
• Serves as a second messenger for some hormones and NTs
• Activates exocytosis of NTS and other cellular secretions
• Essential factor in blood clotting

Homeostasis is chiefly regulated by PTH, calcitriol (vitamin D), and calcitonin (in children)
• These hormones affect bone deposition and resorption
• Intestinal absorption and urinary excretion
Hypercalcemia
• Alkalosis or hyperthyroidism.
•Reduces plasma membrane permeability, inhibits
depolarization of nerve and muscle cells = muscle
weakness, depressed reflexes and cardiac arrhythmia
Hypocalcemia
• Vitamin D deficiency, diarrhea, pregnancy, lactation or hyperthyroidism.
Increases Na+ permeability of plasma membranes = over excitable nervous and muscular system

58
Q

Phosphates

A

Relatively concentrated in ICF due to hydrolysis of ATP and other phosphate compounds

Activates many metabolic pathways by phosphorylating enzymes and substrates such as glucose

Buffers that help stabilize the pH of body fluids
• Continually lost by glomerular filtration
• If plasma concentration drops, renal tubules reabsorb all filtered phosphate
•PTH increases the excretion of phosphate to increase calcium in the CF
•Excretion rate effected by the pH of the urine

59
Q

pH

A

The pH is important to maintain the right balance in our bodies. It helps with various bodily functions.

Slight deviations from normal ph
- shut down entire metabolic pathways
- alter the structures and functions of macromolecules

60
Q

Acid

A

Any chemical that releases H+ in solution (pH < 7)
• Strong acids such as hydrochloric acid (HCI)
ionize freely
- Gives up most of its H*
- Markedly lowers pH of a solution

• Weak acids such as carbonic acid (HCO3) ionize only slightly
-Keeps most H* chemically bound
-Does not affect pH

61
Q

Bases

A

Bases- any chemical that accepts
H+
• Strong bases, such as the hydroxide ion (OH-), have a strong tendency to bind H* markedly raising pH
•Weak bases, such as the bicarbonate ion (HCOz), bind less available H+ and have less effect on pH

62
Q

Buffers

A

Buffer = Any mechanism that resists changes in ph
•Convert strong acids or bases to weak ones

Physiological buffer- system that controls output of acids, bases, or CO,
•Urinary system buffers greatest quantity of acid or base
• Respiratory system buffers within minutes

Chemical buffer- a substance that binds H* and removes it from solution as its concentration begins to rise, or releases H* into solution as its concentration falls
•Restore normal pH in fractions of a second
• Three major chemical buffers: bicarbonate, phosphate, and protein systems

The amount neutralized by chemical buffer systems depends on 2 factors:
• concentration of buffer and
• pH of environment

63
Q

Chemical buffers

A

Buffers
•Bicarbonate:
CO2 + H20 - H2C03 = H05 + H*
- Lungs and kidneys constantly remove Carbon dioxide,which keeps the reaction moving to the left
-To lower pH, kidneys excrete HCO3 keeping the reaction moving to the right, elevating H* in ECF

• Phosphate H2PO,
- Low pH = HPO42- takes up excess H+ to form H2PO4- counteracting the fall in pH by lowering the
concentration of H+ in the solution.
- High pH = H2PO4- directly interacts with hydroxide ions to form water or dissociate into HPO4?-
and H+. Reduced OH levels and the increased levels of H+ counteract the rise in pH.

Protein systems:
•Common in blood plasma fluid and intracellularly (abundance of protein). Each amino acid has at least one COOH and one -NH2. -COOH can act as an acid, donating H, -NH2 can act as abase by accepting a H. In blood, Hb in BC’s acts as a buffer by binding or donating H* (depending ph). In active tissues, levels of CO? increase, reacting with H2O forming H2C03.
•This dissociates into H* and HCO3, lowering the pH. = Hb molecules unloading 02 to become
HHb. HIb then acts as a buffer by accepting H*. When pH levels start to rise, as in the lungs, the HHb unloads the H+, counteracting the increase in pH

64
Q

Respiratory control of ph

A

Respiratory Control of pH
The respiratory buffer system adjusts the pH of the body fluids by raising or lowering the rate and depth of breathing

• CO2 produced by aerobic metabolism
Normally eliminated by lungs at an equivalent rate
•Rising COz and falling pH stimulate peripheral and central
chemoreceptors = increase in pulmonary ventilation
• Conversely, a drop in H* raises pH and reduces pulmonary ventilation
• Metabolic CO, accumulates in CF faster than expelled, lowering
the pH

65
Q

Renal control of ph

A

Kidneys neutralize more acid or base than respiratory system or chemical buffers

Renal tubules secrete H+ into the tubular fluid

• Most binds to bicarbonate, ammonia, and phosphate buffers
• Bound and free H* are excreted in the urine, expelling H* from the body
• Other buffer systems only reduce its concentration by binding it to other chemicals

66
Q

Role of kidneys

A

Fluid regulation

67
Q

Ureter

A

Transport

by basically collect collect the urine right, which is a waste product from the from the kidney, and I export it and transport it to the next area.

68
Q

Bladder

A

Storage of the urine

69
Q

Urethra

A

The transport vessel from the bladder

70
Q

Blood vessels

A

Renal artery and vein important for filtration

71
Q

Base unit

A

Base unit- nefron

72
Q

Aldosterone

A

Hormone: aldosterone
Site location: adrenal cortex
Regulation: regulate electrolyte balance by increasing the sodium reabsorption as well as potassium excretion in the kidneys leading to an increase in blood volume and pressure.
Effects: reduce blood volume so it regulates blood volume by changing the fluid levels.
Site of action: kidneys

73
Q

ANP

A

Hormone: ANP
Site location: artria of the heart in the cardiac cells
Regulation: blood pressure and fluid balance by promoting the excretion of sodium and water in urine
Effects: increase blood volume increase blood pressure
Site of action: kidney

74
Q

ADH

A

Hormone:ADH
Site location:hypothalamus
Regulation: regulate water balance by increasing the water reabsorption in the kidneys and constricts the blood vessels as well by increasing the blood pressure
Effects: anti directic
Site of action:

75
Q

PTH

A

Hormone: PTH
Site location:
Regulation: regulate calcium and phosphate levels in the blood by stimulating the release of calcium from bone and increase the calcium reabsorption in the kidneys
Effects: pulling back of calcium. Released due to low levels of calcium in blood
Site of action: proximal descending part of nephron

76
Q

Buffering

A

A balanced equilibrium equation. So u pump more hydrogen ions, which is acidity on one side. The buffer will allow it to just tip over the wave. Like a seesaw.

77
Q

Why do we have buffers

A

The build up of acidity in the body is able to be balanced out through buffers

A n P 2 (16 decks)

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