Oby1Tt1 - Urinary Tissues

Front 1

List the structures of the urinary system

Back 1

A pair of kidneys

Two ureters

Bladder

Urethra

Front 2

What are the functions of the urinary system?

Back 2

To maintain water and salt balance in the blood

To filter and remove toxins

Front 3

What endocrine functions does the urinary system have?

Back 3

Ability to regulate blood pressure and volume via JGA

Production of erythropoietin in response to hypoxia

Hydroxylation and activation of vitamin D

Front 4

What is the renal hilum?

Back 4

The inner border of the kidney where the nerves, blood vessels and ureter enter or leave

Front 5

How much blood flows through the kidneys per minute? Of this, how much flows through the glomerulus, and how much is actually filtered?

Back 5

1.25L/min, of which 675mls, of which 125mls

Front 6

What is the average rate of urine output?

Back 6

0.3-20mls/min depending on liquid consumption

Front 7

What are the two types of nephron? What is the difference between them?

Back 7

Cortical (85%) - are found higher up and its loop of Henle doesn't extend all the way to the inner medulla

Juxtamedullary (15%) - lower down, loop of Henle extends to inner medulla

Front 8

What are the vascular and urinary poles?

Back 8

The two ends of the Bowman's space, the vascular one being where the arterioles are present and the urinary one being where the PCT begins

Front 9

What cell type is present on the parietal layer of Bowman's space?

Back 9

Simple squamous epithelium

Front 10

What cell type is present on the visceral layer of the Bowman's space?

Back 10

Podocytes

Front 11

What are mesangial cells? What are their two types and the functions of each type?

Back 11

Specialised smooth muscle cells that work to regulate blood flow through glomerulus

Extraglomerular - relay information from macula densa to intraglomerular

Intraglomerular - to regulate blood flow by constricting vessels

Front 12

What are the 3 layers to the blood-urine barrier?

Back 12

- a fenestrated capillary

- a Basal lamina

- podocyte slit pores

Front 13

What are the 3 layers of the Basal lamina of the kidney filtration barrier?

Back 13

Lamina rara interna

Lamina densa (including type 4 collagen)

Lamina rara externa including collagen and heparin sulphate

Front 14

What are the two anatomical regions of the proximal tubule?

Back 14

Pars convoluta (Wilkins describes this as S1, S2)

Pars recta (S3)

Front 15

What are the 3 regions of the loop of Henle?

Back 15

Descending, hairpin and ascending

Front 16

The distal tubule is composed of which sections?

Back 16

Ascending limb of Henle

Macula densa

Pars convoluta

Front 17

What type of epithelium is the proximal tubule composed of?

Back 17

Leaky cuboidal epithelium

Front 18

What type of epithelium is Henles loop composed of?

Back 18

Simple squamous

Front 19

What type of epithelium is the distal tubule composed of?

Back 19

Cuboidal cells

Front 20

What is reabsorbed into the PCT?

Back 20

Sodium

Chloride

Glucose

Amino acids

Vitamins

Water

Front 21

What are canaliculi?

Back 21

Invaginations of the plasma membrane between microvilli

Front 22

Describe the morphology of the PCT cuboidal epithelium

Back 22

Brush border for bulk reabsorption

Canaliculi for increased SA

Long mitochondria to provide ATP for transport

Lots of lysosomes for endocytosis and protein breakdown

Front 23

Why is the descending loop of Henle so permeable to water?

Back 23

It contains constitutively active aquaporin 1 channels

Front 24

What is the purpose of the descending loop of Henle?

Back 24

Water reabsorption

Front 25

What is the purpose of the ascending loop of Henle?

Back 25

Na and Cl reabsorption

Front 26

What is the vasa recta?

Back 26

Thin straight vessels that surround the loop of Henle and take up water/ions that have been absorbed from it

Front 27

What are the 3 parts of the DCT?

Back 27

Pars recta

Macula densa

Pars convoluta

Front 28

What is the purpose of the DCT?

Back 28

Ion exchange and maintaining acid-base balance

Front 29

How does the morphology of the DCT cells differ from that of PCT cells?

Back 29

DCT are shorter and have no brush border. They also have elaborate Basal membrane invaginations and ion pumps for transport

Front 30

What is the function of the pars recta of the DCT? How does it do this?

Back 30

Formation of concentrated urine. It pumps Na into the interstitium, without allowing water to follow, which concentrates the urine

Front 31

What is JGA and what are its 3 components?

Back 31

Juxtaglomerular apparatus

Composed of a macula densa, Extraglomerular mesangial cells and Juxtaglomerular cells

Front 32

What do cells of the macula densa respond to and how do they do this?

Back 32

They sense low Na concentration of the tubular fluid and release prostaglandins to the Extraglomerular cells in response

Front 33

What is the response of the juxtaglomerular cells to stimulation by the Extraglomerular cells?

Back 33

Produce renin

Front 34

What is the function of the JGA?

Back 34

Regulates blood pressure, renal blood flow, GFR

Front 35

What does renin Secretion achieve and which system does it use to achieve this?

Back 35

Peripheral vasoconstriction via renin-aldosterone-angiotensin system

Front 36

Describe the layers of the ureter. What type of epithelium is the mucosa?

Back 36

Mucosa which lines the lumen

Muscular coat

Fibrous connective tissue covering

Mucosa is transitional, around 3-5 layers thick

Front 37

How is the epithelium of the bladder adapted?

Back 37

It has thickened plaque on its apical surface which contains glycoprotein to protect the epithelium. The plaques are impermeable to salt and water so they act as an osmotic barrier

Front 38

What conveys urine from the DCT to the ureter?

Back 38

The collecting duct

Front 39

Describe how the different types of collecting ducts are arranged?

Back 39

Cortical converge to form a medullary, which converge to form a papillary

Front 40

How much urine can the bladder hold on average?

Back 40

500mls for 5 hours

Front 41

How many layers of smooth muscle are there in the detrusor?

Back 41

3 - 2 longitudinal sandwiching and interlacing a circular layer

Front 42

What is acute renal injury?

Back 42

Acute loss of kidney function

Front 43

What may cause pre-renal failure?

Back 43

Reduced cardiac output

Haemorrhage

Infection

Drugs

Dehydration

Front 44

What may cause intra-renal failure?

Back 44

Tissue destruction by toxic compounds

Front 45

What may cause post-renal failure?

Back 45

Obstruction in ureter, eg by stones or tumours

Front 46

What is CKD and what are the most common causes?

Back 46

Chronic kidney disease

Caused by diabetes

Hypertension

Glomerulonephritis

PCKD

Front 47

What are the two types of Glomerulonephritis?

Back 47

NephrOtic syndrome => protein in urine

NephrItic syndrome => blood in urine