Urinary System Flashcards
1
Q
The Major excretory system of the body.
Eliminates waste and maintains fluid balance
A
Urinary System
2
Q
Filter blood and produce urine
A
Kidneys
3
Q
carry urine to the bladder
A
Ureters
4
Q
stores urine
A
Bladder
5
Q
removes urine from the body
A
Urethra
6
Q
Urine contains?
A
-Excess water and ions
-Metabolic wastes
-Toxic substance
7
Q
Functions of the Urinary System
A
Excretion
Blood Volume &Pressure Regulation
Solute Concentration
pH Balance
RBC Production
Vitamin D Synthesis
8
Q
The renal artery and nerves enter.
The renal vein, ureter, and lymphatic vessels exit.
A
Hilum
9
Q
The hilum opens into a cavity called the__________?, which contains blood vessels, part of the system for collecting urine, and adipose tissue
A
Renal Sinus
10
Q
The outer layer.
-Contains structures responsible for blood filtration.
A
Cortex
11
Q
The inner region, made of cone-shaped renal pyramids.
-These pyramids consist of tubes and ducts that modify fluid into urine.
A
Medulla
12
Q
Urine forms here and exits through the renal papillae ( Tips of the pyramid)
A
Renal Pyramids
13
Q
Funnel-shaped chambers surrounding the papillae that collect urine. Small calyces merge into larger ones and empty into the renal pelvis.
A
Calyx
14
Q
A large, funnel-shaped chamber in the renal sinus, which narrows at the hilum to form the ureter.
A
Renal Pelvis
15
Q
Transports urine from the renal pelvis to the urinary bladder. This system ensures efficient urine production, collection, and transport.
A
Ureter
16
Q
is the histological and functional unit of the kidney. About 1.3 million per kidney, distributed in the cortex and medulla. It consists of specialized structures including small tubes that are called tubules.
A
Nephron
17
Q
Filters blood.
A
Renal Corpuscle
18
Q
returns filtered substances to the blood.
A
Proximal Convoluted Tubule
19
Q
Conserves water and solutes.
A
Loop of Henle
20
Q
rids the blood of additional wastes.
A
Distal Tubule
21
Q
Explain Urine Flow
A
ducts → papillary ducts → calyces → continues toward the ureter.
22
Q
Types of Nephron
A
- Juxtamedullary nephrons
- Cortical Nephrons
23
Q
*Located near the
medulla with long loops
of Henle.
*Adapted for water
conservation.
*Make up about 15%of
nephrons.
A
Juxtamedullary Nephrons
24
Q
Have renal corpuscles
that are distributed
throughout the cortex
*Located in the outer
cortex with shorter
loops of Henle.
A
Cortical Nephrons
25
has two layers: an outer layer made of
**simple squamous epithelial cells**, and an
inner layer with specialized **podocytes**
that wrap around the **glomerular
capillaries.**
Bowman Capsule
26
is **highly efficient at filtration** due to several key features
Renal Corpuscle
27
The Glomerular capillaries have pores that **allow small molecules to pass** but **block large proteins and blood cells**.
Porous Capillaries
28
The **inner Bowman capsule layer**
contains specialized cells that **form gaps to aid filtration.**
Porous inner layer of Bowman capsule
29
The difference in diameter between the afferent
arterioles(supplies blood to the glomerulus for filtration) and efferent arterioles(transports the filtered blood away from the glomerulus)creates
high pressure in the glomerulus, enhancing filtration.
High Pressure
30
**supplies blood** to the glomerulus for filtration
Afferent arterioles
31
**transports the filtered blood away** from the glomerulus
efferent arterioles
32
filters blood and **produces filtrate that enters the Bowman capsule**, starting urine production.
Filtration membrane
33
is a **key regulatory structure near the glomerulus**, consisting of specialized cells in the afferent arteriole and distal convoluted tubule.
juxtaglomerular apparatus
34
Specialized smooth **muscle
cells around the afferent arteriole.**
Juxtaglomerular cells
35
**Cells in the distal convoluted tubule**
next to the renal corpuscle.
Madula Densa
36
**modifies** the filtered fluid into urine.
Renal Tubule
37
**lined with cuboidal cells**
and many microvilli for surface area.
proximal convoluted tubule
38
a **shorter section with cuboidal cells** and fewer microvilli.
distal convoluted tubule
39
which **carries the fluid toward the renal pyramids.**
Collecting duct
40
**Blood flows through a system** of vessels in the kidneys, starting with the_________? branching from the **abdominal aorta**
Renal arteries
41
Between renal pyramids.
Interlobar arteries
42
Arch between cortex and medulla
Arcuate Arteries
43
Branch from arcuate arteries into the cortex.
Interlobular arteries
44
**Deliver blood** to glomerular capillaries.
Afferent Arterioles
45
**Carry blood away** from the glomerulus
Efferent arterioles
46
**Surround the tubules and loops of Henle.**
**Vasa recta** are specialized peritubular capillaries in the medulla.
Peritubular capillaries
47
Blood pressure within the glomerular capillaries.
- **Outward pressure** forces fluid and solutes into the Bowman capsule.
Glomerular Capillary Pressure
48
**Inward pressure** opposing filtration.
- Caused by fluid pressure in the Bowman capsule.
- Regulates the flow of filtrate entering the capsule.
Capsular Pressure
49
**Inward pressure due to plasma proteins** in glomerular capillaries.
- Proteins attract water back into capillaries via osmosis.
Colloid Osmotic Pressure
50
**Higher at the end of glomerular capillaries** due to **increased protein
concentration**.
- **Opposes filtration** and balances outward pressures.
Colloid Osmotic Pressure
51
is the **transport of water and solutes from the filtrate into the blood.**
Tubular Reabsorption
52
**Highly permeable to water**, allowing
water to exit by osmosis.
- Concentrates filtrate to about
**1200 mOsm/L.**
Descending Limb
53
**Impermeable to water** but allows
solute reabsorption via diffusion and
active transport.
- **Reduces filtrate concentration to
~100 mOsm/L by the end**
Ascending Limb
54
**Reabsorption of solutes**b (K+, H+)
occurs under hormonal control.
**Facilitates osmosis and
maintains body’s fluid balance**.
Distal Convoluted Tubule and Collecting Duct
55
Hydrogen ions, some by products of
metabolism, and **some drugs are actively
secreted into nephron**
Tubular Secretion
56
What are the (3) major hormonal mechanisms
1. antidiuretic hormone mechanism
2. angiotensin-aldosterone mechanism
3. atrial natriuretic hormone
57
Initiated under **low blood pressure conditions**
renin-angiotensin-aldosterone mechanism
58
**Secreted by neurons** in posterior pituitary
antidiuretic hormone mechanism
59
**Secreted from cardiac muscle cells** in right Atrium of heart when **blood pressure in right Atrium increases above normal**
atrial natriuretic hormone
60
**small tubes that carry urine from the renal pelvis** of the
kidney to the posterior inferior portion of the urinary bladder.
Ureters
61
a **hollow, muscular container**
that lies in the pelvic cavity just
posterior to the pubic
symphysis
Urinary Bladder
62
**stores urine**
* can hold a maximum
amount of **1000 mL of
urine**
Urinary Bladder
63
an **inflammation of the urinary
bladder**, which usually results
from a bacterial infection
Cystitis
64
the tube that carries urine from
the urinary bladder to the
**outside of the body**
Urethra
65
is activated by **stretch of
the urinary bladder wall.**
micturition reflex
66
**produced by stretch receptors**
are carried along pelvic nerves to the sacral region
of the spinal cord.
Action Potentials
67
**are carried by parasympathetic nerves** to contract the smooth muscles of the
urinary bladder.
Action Potentials
68
**Peristaltic contractions of the ureter** force
**irregularly shaped kidney stones** through the
narrow ureter, which causes inflammation and
pain.
* calcium oxylate.
Kidney Stone
69
It consists of all of the **fluid inside the cells** of the body Part of the cytoplasm of the cell, and it has a similar composition in all the
cells of the body **40% of the bodys total weight**
Intracellular Fluid Compartment
70
This fluid consists of the **fluid outside all the cells** of the body 20% of thr bodys total weight
Extracellular Fluid Compartment
71
Two mechanisms regulate ion levels in
extracellular fluid
Thirst Regulation
Ion Concentration Regulation
72
Neurons in the hypothalamus that **control water intake by regulating the sensation of thirst.**
Thirst Center
73
Force that causes the net **movement of
water molecules** toward an area with a
higher solute concentration.
Osmotic Pressure
74
Stimulates both **water reabsorption** in the kidneys and
thirst.
ADH (Antidiuretic Hormone)
75
Causes aldosterone
secretion from the
adrenal cortex.
High K+ levels
76
Reduces aldosterone
secretion.
Kidneys retain more
K⁺
Low K+ levels
77
Dehydration.
Plasma loss (e.g.,
circulatory shock).
Tissue damage (e.g.,
severe burns
Factors Increasing K+ levels
78
Increased Na⁺ permeability
→ **Hyperexcitability**, muscle tetany.
Low Ca2+
79
Reduced Na⁺ permeability
→ **Decreased excitability**, muscle
weakness, or paralysis.
High Ca2+
80
Secreted when **blood Ca²⁺
is low.**
Parathyroid
Hormone (PTH)
81
Essential for Ca²⁺
absorption in the intestines.
**Synthesis depends on
sunlight**; deficiency reduces
Ca²⁺ absorption.
Vitamin D3
82
**Secreted by thyroid gland**
when blood Ca²⁺ is high.
**Inhibits osteoclasts**,
preventing bone
degradation.
Calcitonin
83
What is the body’s normal blood pH
7.35-7.45
84
affects the activity of enzymes
and interact with many
electrically charged molecules.
Hydrogen Ions (H+)
85
Releases H+ into a solution
Acids
86
Removes H+ from a
solution
Bases
87
They completely dissociate
into its component ions.
Strong Acids
Strong Bases
88
They do not completely
dissociate .
Weak Acids
89
Reduces the concentration
of H+ through binding
Weak Bases
90
Three major mechanisms that regulate H+ concentration
*Buffer System
*Respiratory System
*Kidneys
91
They Resist changes in pH
Buffers
92
Three major buffer systems
1. Bicarbonate Buffer System
2, Protein Buffer System
3. Phosphate Buffer System
93
Regulates the pH of blood by balancing the levels of carbonic acid, bicarbonic ion, and carbon dioxide.
Bicarbonate Buffer System
94
The **capacity of proteins to function as
buffers** due to the functional groups of
amino acids.
**Provides 3/4s of the body’s buffer capacity**
because of their high concentration.
Protein Buffer System
95
Helps regulate intracellular fluid pH.
Phosphate buffer system
96
Regulates Acid-Base Balance through breathing
Respiratory Regulation of Acid-Base Balance
97
Cells of the **kidney tubules directly regulate acid-base balance** by increasing or decreasing both the rate of H+ secretion into the filtrate and the rate of HCO3- reabsorption.
Renal Regulation of Acid-Base Balance
98
When pH level is **below
7.35**
Acidosis
99
When pH level is **above
7.45**
Alkalosis
100
**Too much CO2 in body**,
caused by **Inadequate ventilation of lungs.**
(Hypoventilating)
Respiratory Acidosis
101
Results from all conditions that **decrease the pH of the body fluids below 7.35**
Metabolic Acidosis
102
**Too much elimination of CO2**, caused by **hyperventilation** of lungs
Respiratory Alkalosis
103
Results from all conditions that **increase the pH of the body fluids above 7.45**
Metabolic Alkalosis
