This lesson will increase your knowledge of concepts
covered in the following TEKS for biology:
4.b – Investigate and identify cellular processes including homeostasis,
permeability, energy production, transportation of molecules, disposal of
wastes, function of cellular parts, and synthesis of new molecules
5.c – Sequence the level of organization in multicellular organisms to relate
the parts to each other and to the whole
9.a – Compare the structures and functions of different types of biomolecules
10.a – Interpret the functions of systems in organisms
10.b – Compare the interrelationships of organ systems to each other and to
the body as a whole
11.a – Identify and describe the relationships between internal feedback
mechanisms in the maintenance of homeostasis
11.b – Investigate and identify how organisms respond to external stimuli
Previous Lesson
Diseases of the
Endocrine System
Question: Would a person
that is somewhat lethargic
and overweight be suffering
hyperthyroidism
(high thyroid production) or
hypothyroidism
(low thyroid production)?
Why?
Hypothyroidism: Low Thyroxine
Pituitary
Thyroid Stimulating Hormone
Thyroid
Treatment:
Synthetic thyroid
pills
Low Thyroxine
Low Metabolism and High Weight
Question: If a person is in an area
where a nuclear reactor has released
radioactive iodine, why would
authorities recommend they take
iodine pills?
From Harvard
Health Letter
Nuclear Reactor Accident
Destruction of nuclear reactor
Release of radioactive iodine
Taking iodine in pills would
Uptake of radioactive iodine by thyroid
block uptake of radioactive
iodine
by thyroid,
thereby
Radioactive
iodine causes
preventing
mutations ofcancer
DNA in thyroid cells
Thyroid cancer
Question: Why does a person with
Type II diabetes have high blood
sugar, and why is this so
dangerous to a person’s health?
Type II Diabetes
Based on: Time, November 5, 1990
•Cells of body
become resistant
to the effects of
insulin
•Sugar cannot
enter cells
•Concentrations of
sugar in blood
become too high
Effects of
Uncontrolled
Diabetes and
High Blood
Sugar
Based on: Newsweek, September 4, 2000
Today’s Lesson
Kidneys and the
Urinary System
Major Parts of the Machine
food, water intake
oxygen intake
Digestive System
nutrients,
water,
salts
Based on: Starr, C., Biology:
Concepts and Applications,
Brooks/Cole
Respiratory System
elimination
of carbon
dioxide
oxygen
carbon
dioxide
Circulatory System
Urinary System
water
solutes
elimination
of food
residues
rapid transport
to and from all
living cells
elimination of
excess water
salts, wastes
Overview of Lesson
•
•
•
•
Formation of urine
Urinary system
Water balance and alcohol
Problems of the urinary
tract
When protein is broken down
in the body, it results in
nitrogenous waste that must
be eliminated from the body
Protein
Based on: Mader, S., Inquiry Into Life, McGraw-Hill
Examples
of Amino
Acids
Based on: Mader, S., Inquiry Into Life, McGraw-Hill
All 20 amino acids have a nitrogen group (NH2).
When broken down for energy, the nitrogen group
is converted to ammonia (NH3).
Circulatory
System
Ammonia is
converted into urea
by the liver. Urea is
then transported in
the blood to the
kidneys where the
urea is removed
from the blood.
Based on: Mader, S., Inquiry Into Life
Urea is less toxic than ammonia
and can be transported in the
blood to the kidney
O
H2N - C - NH2
urea
Formation of Urine
Amino acids in protein are broken down,
resulting in production of ammonia
Ammonia is converted to urea in liver
Urea travels in blood to kidneys, where
removed from blood and incorporated
into urine
Overview of Lesson
• Amino acids, ammonia and
urea
• Urinary system
• Water balance and alcohol
• Problems of the urinary
tract
Urinary System
Based on: Mader, S., Inquiry Into Life, McGraw-Hill
Anatomy of
the Kidney
Based on: Mader, S., Inquiry Into Life, McGraw-Hill
Urine Formation by Nephron
Blood pressure forces water, glucose,
amino acids and urea from capillaries into
nephron
Glucose and amino acids are reabsorbed
into blood from nephron
Some water is reabsorbed into blood
Urine is urea and salt concentrated in water
Nephron
Based on: Mader, S., Inquiry Into Life, McGraw-Hill
Urine moves from the
collecting ducts through the
kidney pelvis to the ureter
Based on: Mader, S., Inquiry Into Life, McGraw-Hill
Urine moves from the kidneys,
through the ureters to the bladder
and finally through the urethra
Based on: Mader, S., Inquiry Into Life, McGraw-Hill
Overview of Lesson
• Amino acids, ammonia and
urea
• Urinary system
• Water balance and alcohol
• Problems of the urinary
tract
Regulation of Water Balance
Brain monitors water content of blood
If low water content, pituitary releases ADH
ADH travels in blood to nephron
ADH causes more water to move from urine
back into blood
Nephron
Based on: Mader, S., Inquiry Into Life, McGraw-Hill
Alcohol consumption
suppresses the production of
ADH by the pituitary.
Why would this result in
dehydration and a hangover?
Overview of Lesson
• Amino acids, ammonia and
urea
• Urinary system
• Water balance and alcohol
• Problems of the urinary
tract
Incontinence (urine leakage)
• More than 10 million Americans experience
incontinence
• Most do not seek treatment
• Treatment can improve or eliminate the
problem 90% of the time
Causes of Incontinence
Stress incontinence: leaking small amounts
of urine when coughing, lifting, or exercising
Urge incontinence: the bladder suddenly and
unexpectedly contracts and expels urine
Overflow incontinence: bladder cannot
completely empty so urine dribbles
Treatments for Incontinence
• Kegel exercises to strengthen the urinary
sphincter
• Medicines that increase the sphincter’s ability
to contract
• Surgery to strengthen the pelvic muscles or to
lift the bladder
• Retrain the bladder to increase its storage
capacity (allowing 3-4 hours between urinating)
• Drugs to prevent urge incontinence
• Surgery to remove part of prostate gland if
responsible for overflow incontinence
Kidney stones form in the kidney
pelvis. There are 4 types of stones.
•Calcium stones
(most common)
•Uric acid stones
•Bacteria caused stones
•Cystein stones
Based on Mayo Clinic Health Letter
Kidney stones cause pain when
they pass down the ureters to the
bladder and urethra
Based on: Mader, S., Inquiry Into Life, McGraw-Hill
Treatments for Kidney Stones
• Small stones may pass with no pain
• Larger stones may pass but cause extreme of
pain, requiring a lot pain medication
• Stones that are too large to pass may require
surgical treatment including:
– using a ureteroscope to go up and snare the
stone
– using a nephroscope to crush the stone and
retrieve it
– using shock wave lithotripsy where a person
is submerged in water containing shock
waves to pulverize the stones
Urinary Tract Infection (UTI)
• Second most common infection following
respiratory infections
• UTI occur when bacteria (E. coli) from the
digestive tract get into the opening of the
urinary tract and multiply
• Bacteria first infect the urethra, then move to
the bladder and finally to the kidneys
• UTI tend to occur more in women than men
Women may have more UTIs than men because:
1) they have a shorter urethra, allowing quicker
access to the bladder
2) the urethral opening is nearer the anus
3) intercourse may result in UTIs in women
Based on: Harvard Medical School Family Health Guide
Symptoms of UTIs
• Urge to urinate but only small
amount of urine produced
• Pain and burning sensation in
bladder
• Fever
• Blood in urine
Diagnosis and Treatment
• Doctors check urine for white and red
blood cells and bacteria
• Bacteria grown in culture to
determine which antibiotic will work
the best
• UTIs are treated with antibiotics and
are often cured within 1 or 2 days
Kidney Disease and Ethnicity
• Kidney disease 26 million Americans
• African Americans five times likely to
require dialysis or kidney transplant
• Possible reasons
– Lack of health care
– Genetic component
– Diabetes
– Hypertension
Next Class
Exam II
(Lessons and Labs)