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Phase 1 > SUGER: Week 3 > Flashcards

SUGER: Week 3 Flashcards

1
Q

Is the kidney retro or intraperitoneal

A

It is retroperitoneal

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2
Q

What vertebral levels does the kdiney extend from and to

A

From T12 to L3

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3
Q

What is the apex of the renal pyramids known as

A

Renal papilla

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4
Q

What is the role of the renal papilla

A

Connects to the minor calyx

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5
Q

What is the role of the minor calyx

A

Collects urine from the renal pyramids

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6
Q

Describe the path of urine through the kidney structures

A

Renal pyramids -> Minor calyx -> major calyx -> Renal pelvis -> ureter -> bladder

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7
Q

What is the renal hilum

A

Gateway to the kidney

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8
Q

Where are medullary rays located

A

In the cortex leading into the medulla

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9
Q

What provides the striated appearance of the cortex

A

The medullary rays

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10
Q

What are the ureters made of

A

Smooth Muscle

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11
Q

How does the ureter move urine from the kidneys to the bladder

A

Via peristalsis

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12
Q

What is the blood supply of the ureter

A

Upper - Renal arteries
Middle - Common iliac arteries + Gonadal arteries
Lower - Internal iliac arteries

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13
Q

What is the nerve supply of the ureter

A

Testicular nerve plexus

Renal nerve plexus

Hypogastric nerve plexus

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14
Q

Where is the urinary bladder located

A

In the pelvic cavity

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15
Q

Where is the median umbilical ligament located

A

At the apex of the bladder extending to the umbilicus

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16
Q

What is the name of the muscle that is contained within the bladder

A

Detrusor muscle

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17
Q

How many sphincters does the male bladder have

A

Two: external and internal

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18
Q

What is the blood supply of the bladder

A

Males: Inferior Vesical artery

Females: Vaginal Artery

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19
Q

What are the inferior vesical artery and vaginal artery branches of

A

The internal iliac artery

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20
Q

What is the sympathetic nerve supply of the bladder

A

Superior + Inferior hypogastric plexuses

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21
Q

What does the trigone of the bladder consist of

A

2 Ureteric orifices
1 Internal urethral orifice

Mucosal flaps allow unidirectional movement of urine

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22
Q

What are the different parts of the male prostate and what epithelium are they lined by

A

Preprostatic - Transitional
Prostatic - Transitional
Membranous - Pseudostratified columnar
Spongy urethra - Proximally pseudostratified and distally stratified squamous epithelium

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23
Q

What is the difference in the glands present in the urethra in males and females

A

Males have bulbourethral glands

Females have bartholin glands

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24
Q

What structure do the collecting ducts drain urine into

A

The renal pelvis

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25
Q

What structure do the ureter move alongside to the bladder

A

Psoas major

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26
Q

Are ureters retro or intraperitoneal

A

Retroperitoneal

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27
Q

Describe the pathway of the ureters into the bladder

A
  1. Move along psoas major muscles
  2. Crosses pelvic brim + enters pelvic cavity
  3. Runs down lateral pelvic walls
  4. Enters ureteric orifices via one-way valves
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28
Q

What consists of the renal corpuscle

A

Glomerulus
Endothelial cells
Bowman’s capsule

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29
Q

What is the role of the renal corpuscle

A

Filters blood plasma

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30
Q

What does the difference in diameter of the afferent and efferent arterioles achieve

A

Allows a huge + constant hydrostatic pressure along the glomerulus

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31
Q

What are the glomerulus supported by (cell-wise)

A

Mesangial cells

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32
Q

Three role of mesangial cells

A
  1. Contract smooth muscle walls of afferent arterioles to reduce GFR
  2. Structural support for capillaries
  3. Phagocytosis of glomerular basement membrane breakdown products
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33
Q

Where are principal cells found

A

DCT and collecting ducts

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34
Q

Role of principal cells

A

Changes balance of Na+ and K+ in filtrate

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35
Q

What mediates the action of the principal cells

A

Aldosterone

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36
Q

What does an increase in aldosterone cause in the principal cells

A

Causes an increased Na+ channel expression on apical membrane

Causes increased Na+/K+ ATPase on basolateral (3Na out and 2K in)

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37
Q

Apart from the kidneys, where else does aldosterone have an effect at

A

At the salivary glands + Gut (absorption of Na+ and secretion of K+)

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38
Q

Describe the structure of the male spermatic duct from the testicles to the epididymis

A
  1. Convoluted seminiferous tubules
  2. Straight seminiferous tubules
  3. Rete Testis
  4. Efferent ductules
  5. Epididymis
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39
Q

Where are leydig cells found

A

Between the seminiferous tubules

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40
Q

Role of leydig cells

A

Produce testosterone

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41
Q

Where does meiosis in males take place

A

Seminiferous tubules

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42
Q

What are the seminiferous tubules lined by

A

Stratified epithelium, sertolli cells and germ lines - Germinal epithelium

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43
Q

What is the chromatin in germinal cells called

A

Spermatogonia

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44
Q

What do spermatogonia develop into before entering the testis-blood barrier

A

Spermatocytes

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45
Q

Role of sertolli cells

A

Nurse cells that develop nurturing developing sperm

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46
Q

How long does sperm production take place

A

64 Days

NOTE: A wave of maturation moves down the tubules until the sperm reaches the blood-testis barrier

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47
Q

What is the role of the renin-angiotensin system

A

Maintain + regulate blood pressure

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48
Q

Describe the renin-angiotensin system

A
  1. Renin is produced by juxtaglomerular cells as PRORENIN
  2. Renin is released by juxtaglomerular cells when there is a DECREASED arterial pressure.
  3. Intrinsic reactions cleave prorenin to renin
  4. Renin acts on angiotensiongen -> angiotensin I (loses 2 AA)
  5. Angiotensin -> angiotensin II by ACE enzymes in the lung endothelium by losing 2AA
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49
Q

Where is angiotensin I converted to angiotensin II

A

Mostly the lungs but also kidneys too

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50
Q

Angiotensin I vs Angiotensin II

A

Angiotensin I is a WEAK vasoconstrictor

Angiotensin II is a STRONG vasoconstrictor

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51
Q

How long does angiotensin II last in the blood vessels

A

apprx 30 mins because it is de-activated very quickly by angiotensinase

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52
Q

How does angiotensin II affect the blood pressure

A

Vasoconstriction

Decreased excretion of Na and H20 by kidneys

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53
Q

What is the result of a decreased excretion of Na by the kidneys

A

Increased ECF volume

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54
Q

Angiotensin II afefct in veins vs arterioles

A

Veins do not constrict as much as arterioles - increases TOTAL PERIPHERAL RESISTANCE

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55
Q

What two ways does angiotensin act in the body

A
  1. Acts directly on kidneys to cause salt and water retention
  2. Causes adrenal glands to secrete aldosterone which increases Na and H20 reabsorption by kidney tubules
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56
Q

Explain the direct-acting nature of angiotensin II

A

Constricts arterioles to reduce pressure in peritubular capillaries + increase pressure gradient from tubules to capillaries (more-rebasorption)

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57
Q

How does the RAAS system function when salt intake varies

A
  1. Large intake of salt increases ECF volume + arterial pressure
  2. Increased arterial pressure causes increased blood flow through the kidneys
  3. Increased blood flow lowers renin secretion so less Na+ is retained.
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58
Q

What are the two components of the aicd-base buffer system at the kidneys

A
  • A weak acid (H2CO3)
  • bicarbonate salt (NaHCO3)

Check book

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59
Q

Is the phosphate buffer system important in ICF or ECF

A

ICF regulation

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60
Q

What are the main components of the phosphate buffer system

A

HPO42-

H2PO4

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61
Q

How will adding a strong acid like HCL affect the phosphate buffer system

A

HCL will react with NaHPO4 to give NaCl + NaH2PO4

So HCL (strong acid) is replaced by a slightly stronger weak acid, minimising change in pH

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62
Q

How does adding a strong base like NaOH affect the phosphate buffer system

A

NaOH will react with NaH2PO4 -> H20 + Na2HPO4

A strong base is replaced by a slightly stronger weak base minimising change in Ph

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63
Q

How does the phosphate buffer system affect bicarbonate levels in the blood

A

Production of new HCO3- ions which increase net amount of plasma HCO3-

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64
Q

When does the phosphate buffer system take place

A

When all the HCO3- have combined with H+ and we have an excess of H+ still left

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65
Q

Describe the phosphate buffer system

A

Check book

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66
Q

Define a base

A

Proton acceptor

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67
Q

Define an acid

A

Proton donator

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68
Q

Define Base Excess

A

Quantity of acid required to return plasma pH to normal

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69
Q

Define standard base excess

A

Quantity of acid that requires to return ECF to normal pH

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70
Q

Define acidemia

A

Low pH

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71
Q

Define alkalemia

A

High pH

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72
Q

Formula for pH

A

-log10(H+)

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73
Q

What is the anion gap

A

The difference between measured cation + measured anions in the plasma or urine

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74
Q

Why do we calculate an anion gap

A

To identify the cause of metabolic acidosis

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75
Q

Formula for the anion gap

A

([Na+] + [K+}) - ([Cl-]+[HCO3-])

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76
Q

What is the normal range for the anion gap

A

10 - 16

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77
Q

What does a wide anion gap suggest

A

Renal Failure

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78
Q

What does a narrow anion gap suggest

A

Renal tubular acidosis

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79
Q

At what part of the nephron does the phosphate buffer system take place at

A

PCT

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80
Q

How does the phosphate buffer system affect plasma HCO3 levels

A

Increases it

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81
Q

Other than the phosphate buffer system, how else can we produce new bicarbonate ions

A

The ammonia buffer system

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82
Q

Describe the ammonia buffer system

A

Check book

83
Q

What is glutamine broken down into

A

NH3 + alpha ketogluturate

NH3 gains a proton to form NH4+

84
Q

What happens to the alpha keto-gluturate

A

Give two HCO3- ions

85
Q

Where is some of the NH4+ absorbed

A

Collecting Ducts

86
Q

How does the mechanism of acid secretion (bicarbonate re-absorption) change along the nephron

A

At PCT and thick ascending limb of loop of henle - Secondary Active Transport

At DCT and collecting ducts - Primary Active Transport

87
Q

What happens to the proportion of NH4+ during metabolic acidosis

A

Increases it

88
Q

How is repiratory acidosis caused

A

Hypoventilation or COPD

89
Q

How is respiratory alkalosis caused

A

Hypoxia and hyperventilation

90
Q

How is metabolic acidosis caused

A

Renal Failure or excess H+ secretion

91
Q

How is metabolic alkalosis caused

A

Vomiting and volume depletion

92
Q

How does metabolic + respiratory acidosis affect the HCO3-/H+ ratio

A

Decreases it

93
Q

Why does H+ conc. increase in respiratory acidosis

A

Increased pCO2 levels in ECF - H+ in excess

94
Q

Why does H+ conc. increase in metabolic acidosis

A

Decreased HCO3- levels in ECF - H+ in excess

95
Q

What happens to NH4+ levels in repiratory and metabolic acidosis

A

Increases to increase bicarbonate levels again

96
Q

How long does correctin of acidosis take

A

Days

97
Q

What happens to the HCO3-/H+ ration during alkalosis

A

It increases

98
Q

How is HCO3- production affected as less H+ is available for the phosphate and ammonia buffer systems

A

Decreases

99
Q

How is alkalosis corrected at the kidneys

A 
Decreased respiration (Increase CO2 levels)
Increased renal HCO3- excretion: Increased ECF conc. causes increased filtration of HCO3- into the tubules and can't be re-absorbed as H+ ions are not present in the cell
100
Q

How is acidosis corrected at the kidneys

A 
Increased respiration (decrease CO2 levels)
Decreased renal HCO3- secretion
101
Q

What are three major roles of the kidneys

A

Angiotensin II
Erythropoietin
Activation of vitamin D

102
Q

Where is erythropoietin produced

A

Renal cortex interstitium

103
Q

What is the consequence of incontinence to an individual

A
  1. Societal expectation
  2. Taboo subject
  3. Significant cause of misery
  4. Less quality of life
  5. Reduced life-expectancy
104
Q

What are the components of the lower urinary tract

A
  1. Bladder
  2. Bladder Neck
  3. Prostate Gland
  4. Urethra + Urethral sphincter
105
Q

What are three functions of the normal lower urinary tract

A
  1. Prevent leakage of stored urine
  2. Low pressure of stored urine
  3. Allow rapid voiding and at an appropriate time + Place
106
Q

Define micturition

A

This is the process by which the urinary bladder empties when it’s filled

107
Q

How can I identify the bladder trigone

A

The trigone is made of smooth mucosa whilst the rest of the bladder has mucosa arranged as rugae

108
Q

How do the ureter pass into the bladder

A

Obliquely

109
Q

Why do the ureter pass into the bladder obliquely

A

To allow uni-directional movement of urine

110
Q

What does the urogenital diaphragm consist of

A

External sphincter of the bladder

111
Q

What is the external sphincter innervated by

A

Peudendal nerve (supplies motor)

112
Q

Can the micturition process by inhibited

A

Yes, it can be voluntarily inhibited util it is appropriate to begin voiding

113
Q

Why does pressure in the bladder stay low during storage even though it is filling with urine

A

Because the bladder has a compliant nature and an increase in bladder tension causes an increase in its radius.

114
Q

Describe the micturition reflex

A
  1. Stretch receptors in the posterior urethra are stimulated when it begins to fill with urine due to the higher pressure in the urine
  2. Sensory impulses move down pelvic nerves to S2 + S3 spinal cord segments
  3. Parasympathetic fibres carry impulses back to the bladder via pelvic nerves
  4. This causes slight contraction of the detrusor muscles
  5. If the bladder content isn’t voided by then OR the bladder is only partially filled, then the micturition contractions relax again due to detrusor muscles
  6. As the bladder fills further, the strength of detrusor muscle contraction eventually increases, pulling the internal sphincter of the bladder open.
  7. More APs are fired by pelvic nerves as stretch receptors become more stimulated
  8. Pelvic nerve is inhibited if micturition reflex fails to release any urine for a few minutes
115
Q

Describe the voiding phase of micturition

A
  1. Afferent signals are sent to the periaqueductal grey
  2. Project to the pontine micturition centre + cerebrum
  3. Increased afferent activity causes INCREASED urge to void
  4. Voluntary signals to start voiding causes maximal firing from the centre exciting SACRAL PRE-GANGLIONIC NEURONS
  5. Neurons cause the bladder wall to contract, increasing intravesical pressure
  6. Onuf’s nucleus is inhibited which causes relaxation of EXTERNAL URETHRAL SPHINCTER
  7. Even when the sphincter is relaxed, the micturition reflex needs to generate a big enough pressure to expel the urine.
116
Q

Where is the micturition reflex centre located

A

Pons.

117
Q

What type of muscle does the external sphincter consist of

A

Slow twitch - type 1 muscle fibres

118
Q

What is the external sphincter innervated by

A

Peudendal nerve (S2-4) which are inihibited to cause the sphincter to relax

119
Q

What is the internal urethral phincter innervated by

A

Sympathetic - Hypogastric plexus

120
Q

What is the bladder innervated by

A

Pelvic Splanchnic nerves (parasympathetic)

121
Q

Where is ANP produced

A

By the atria

122
Q

What does ANP do

A

Dilates the afferent arterioles and constricts efferent arterioles

This increases GFR which increases blood flow through the vasa recta.

Vasa recta washes out Na and Cl in medullary interstitium which reduces Na re-absorption into the nephrons

Inhibits renin secretion

123
Q

How does Na conc. in blood affect ANP levels

A

Increases it

124
Q

Following micturition, how is the remaining urine in the urethra expelled

A

Contraction of the bulbospongiosus muscle

125
Q

How do we expel small quantities of urine even though the micturition reflex is not strong enough to do so

A

Contraction of abdominal walls which increase pressure applied to the urinary bladder wall.

126
Q

What do primordial germ cells do during embryological development in order to initiate spermatogenesis

A

They migrate into the testis and form SPERMATOGONIA

127
Q

When do spermatogonia begin to mature

A

Only once puberty starts

128
Q

Where does sperm maturation take place

A

In the seminiferous tubules

129
Q

What hormone causes sperm maturation

A

Gonadotropic hormones

130
Q

At what age does spermatogenesis typically occur at

A

13

131
Q

Outline the process of spermatogenesis

A

Check book

132
Q

How is the XY chromosome divided in the sperm

A

They are separated during meiosis I and placed into separate gametes

Gamete receiving X will form a female

Gamete receiving Y will form a male

133
Q

Where is the nucleus of a sperm found

A
  1. Sperm head
134
Q

Where is the sperm acrosome located

A

Anterior 2/3 of the head

135
Q

What organelle forms the acrosome

A

Golgi apparatus

136
Q

What two enzymes are found in the acrosome

A
  1. Hyaluronidase (digest proteoglycans)

2. Proteolytic enzymes (digest proteins)

137
Q

Why do we need hyaluronidase and proteolytic enzymes

A

To allow the sperm to reach the ovum

138
Q

What is found in the tail of the sperm

A

Axoneme

139
Q

What is the axoneme

A

Cilia-like structure (central skeleton of II microtubules)

140
Q

What is found in the body of the sperm

A

Mitochondria

141
Q

What causes the movement of the sperm tail

A
  1. Due to axoneme tubule movement
142
Q

What do leydig cells secrete

A

Testosterone

143
Q

Where is LH secreted

A

Anterior pituitary gland

144
Q

What cell does LH activate

A

Leydig cells

145
Q

What does FSH activate

A

Sertoli cells

146
Q

What hormone stimulates division of the spermatogonia

A

Growth Hormone

147
Q

Where is sperm mainly stored

A

Epididymis

148
Q

How long can sperm be stored for

A

About a month

149
Q

In what state are sperm stored

A

Deeply surpassed + Inactivated

150
Q

What do sertoli cells do during ejaculation

A

They secrete hormones + nutrients which makes sperm motile

151
Q

What pH does ejaculate have to be for optimal activity

A

Slightly alkaline

152
Q

How does an increase in temperature affect sperm lifespan and why is this the case

A

Decreases as metabolic activity increases

153
Q

Where do the seminal vesicles empty into

A

Ejaculatory duct

154
Q

What is the main nutrient by sperm

A

Fructose

155
Q

Where a prostaglandins produced

A

Seminal vesicles

156
Q

What is the role of prostaglandins

A

Aid fertilisation by causing reverse peristalsis in fallopian tubes to assist movement of sperm to ovum

157
Q

What do prostate glands secrete

A

Calcium, citrate,phosphate ions, profibrinolysin

158
Q

What is the aim of prostatic secretions

A

Alkaline property which helps neutralise acidic metabolites in seminal fluids released from sperm + acidic conditions of vaginal secretions

159
Q

What epithelium lines the bulbourethral glands

A

Pseudo stratified columnar epithelium

160
Q

What is the fluid composition of semen

A
  1. 60 % seminal fluid
  2. 30% prostatic fluid
  3. 10% sperm + bulbourethral fluid
161
Q

What does the sperm have to do in order to get through the cervix

A

Break down cervical mucous

162
Q

What are type A spermatogonia

A

Remain outside the blood-testis barrier + produce spermatogonia until they die

163
Q

What are type B spermatogonia

A

These mature into spermatocytes

164
Q

Why is some testosterone produced during fetal life

A

To allow descent of the testes

165
Q

How does the SRY gene affect the genital ridge

A

Causes genital ridge to develop into leydig cells

166
Q

In what part of the body is GnRH released

A

Hypothalamus

167
Q

What does GnRH cause in the pituitary glands

A

Secretion of LH and FSH

168
Q

What is the role of FSH in spermatogenesis

A

The FSH binds to receptors on sertoli cells in the SEMINIFEROUS TUBULES

Causes sertoli cells to grow and produce substances the stimulate maturation (with testosterone)

169
Q

How does testosterone act

A

Locally by diffusing from interstitial into seminiferous tubules

170
Q

How is FSH levels affected if spermatogenesis FAILS

A

It will increase

171
Q

What happens if FSH levels are too high

A

Inhibin is secreted by sertoli cells to stop it

172
Q

What is LH inhibited by

A

Testosterone

173
Q

How does testosterone inhibit LH

A
  1. Decreased secretion of GnRH

2. Acts of anterior pituitary gland

174
Q

Why is meiosis important

A
  1. Prevents polyploidy
  2. Increased variation
  3. Genetic diversity
  4. Chromosomal combinations
175
Q

When does meiosis I start in females

A

Before 12 weeks in fetus

176
Q

When is meiosis stopped at before puberty begins

A

Prophase I

177
Q

What happens at puberty to cause meiosis to continue

A

Increased conc. of LH

178
Q

At what stage is meiosis halted until fertilisation

A

Metaphase II

179
Q

How many chromosomes are present in polar bodies

A

23 chromosomes

180
Q

What is the difference between male and female gonads before 6 weeks

A

None

181
Q

When does sex determination occur embryologically

A

After 6 weeks

182
Q

What structures form by the paramesonephric duct

A
  1. Fallopian tubes
  2. Uterus
  3. Upper 2/3 of vagina
183
Q

How many spermatozoa are produced by one spermatocyte

A

4

184
Q

How many ovum are formed by one egg

A

1

185
Q

What is the difference in maturation location of the sperm and ovaries

A

Eggs have one stage in the ovaries and another in the fallopian tubes

Both maturation stages take place in the testis

186
Q

What factors can affect puberty

A
  1. Nutrition
  2. Genetics
  3. Excersise
  4. Leptin
  5. Insulin
187
Q

When does puberty take place in males

A

9-14 (air 12)

188
Q

What are the signs of male puberty

A

Pubic hair, axillary and facial hair

1st - Testicals enlarged

Spermatogenesis

Odour, mood swings and acne

189
Q

When does puberty take place in females

A

8-14 (air 11)

190
Q

What are the signs of female puberty

A

1st = breast development + Menarche

Growth spurt

Pubic and axillary hair

191
Q

When does menarche take place

A

2.5 years after puberty

192
Q

What structure does the sperm pass through to get to the oocyte

A

Corona Radiata

193
Q

What structure is the zona pellucid located next to

A

Corona Radiata

194
Q

What do sperm undergo when they enter the reproductive tract

A

Capacitation

195
Q

What occurs during capacitation

A

Destabilisation of sperm acrosome to allow penetration of the egg

Chemical changes that increases sperm motility

196
Q

What happens to the glycoproteins and cholesterol in the plasma membrane of sperm during capacitation

A

They are more permeable to calcium ions

197
Q

What hormone controls capacitation

A

FPP

198
Q

Where is FPP produced

A

Prostate gland

199
Q

How does FPP function

A

High conc. in male reproductive system keeps sperm inactive

Dilutes in female reproductive tract

200
Q

What happens at the zona pellucida

A

Sperm binds to corona radiata + enters zona

Binds to ZP3 glycoprotein in zone which bursts the acrosome, releasing enzymes needed to break down zona pellucid

201
Q

What follows penetration of the egg

A

Cortical Reactions

202
Q

Describe the cortical reactions that take place

A
  1. Granules in the secondary oocyte fuse with the egg cell membrane
  2. Granules are released by endocytosis
  3. Inactivates sperm binding receptors hardening the zona pellucid
  4. Prevents additional sperm from binding to the zona
203
Q

When does meiosis II of the egg start again

A

Following fertilisation

204
Q

What are pronuclei

A

These are when there are two nuclei of genetic information which are still surrounded by a membrane and haven’t fused yet

Phase 1 (30 decks)

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