Human Excretory System
composed of
kidney-functional unit of a
kidney- nephron)
lungs (alveoli)
skin (sweat glands)
liver
types of metabolic wastes
Waste
Produced from
Carbon Dioxide
Water
Salts
Nitrogenous wastes
Aerobic Respiration
Aerobic Respiration
Metabolic activities
Breakdown of excess
Amino Acids & Proteins
types of nitrogenous wastes
Ammonia (NH3)
Urea
Uric Acid Crystals
toxicity
Highly Toxic
Moderately Toxic
Minimally Toxic
human excretory system
waste and what its removed by
–
–
–
–
–
carbon dioxide- lungs
water - skin, kidney, lungs
salts - skin, kidney
ammonia - liver
urea - kidney
human excretory system
• consists of the kidneys, ureters, urinary bladder,
urethra and renal circuit (renal arteries and renal
veins)
• kidney includes an outer cortex, middle medulla
and the nephrons
• nephrons include a capsule and a looping tubule
that joins others to form the collecting ducts,
making up the pyramids which empty into the
calyces - lead into the renal pelvis
• nephrons form urine, which passes from the
collecting ducts to the renal pelvis. The renal
pelvis empties into the ureters, which conduct
urine to the urinary bladder, and the urethra voids
the urine from the body.
primary organs of excretion
blood and
urine flow
blood enters the
kidneys via renal
arteries, and leaves
the kidneys via the
renal veins
wastes removed from
the blood leave the
kidneys by the
ureter
kidney
Learn the parts
Functions of the kidneys
1. excrete toxins and
nitrogenous wastes
2. regulate chemical
levels in blood
3. maintain water
balance
4. helps regulate blood
pressure (renin)
label the parts
on a model
label the parts
on a model
1. Renal Vein
2. Renal Artery
3. Renal Calyx
4. Medullary Pyramid
5. Renal Cortex
12. Renal Column
13. Renal Papillae
14. Renal Pelvis
15. Ureter
cross section of human
kidney
label the parts
dissected kidney
1. Renal Capsule
2. Renal Cortex
3. Renal Medulla
4. Renal Pyramid
5. Renal Pelvis
6. Renal Column
7. Renal Calyx
8. Ureter
structures
other organs
• ureters - long narrow tubes with expanded
upper end (renal pelvis) located inside each
kidney. Function is to drain the renal pelvis
to urinary bladder
• urinary bladder- elastic muscular organ
capable of great expansion. Function si
storage of urine and voiding
• urethra – passage of urine from bladder to
outside of body. Passage of semen from
male body
formation of urine
occurs by a series of three processes
that take place in successive parts of the
nephron
• filtration
• reabsorption
• secretion
the nephron
The nephron begins with Bowman's capsules,
which surrounds the glomerulus, a ball of
capillaries arising from an afferent arteriole
of the renal artery. Leaving the glomerulus
is an efferent arteriole, which forms the
peritubular capillaries, where reabsorption
takes place. These spread over the nephron
to later form a venule that joins others to
make up the renal vein.
nephron in detail
the nephron
Bowman's capsule leads to the proximal
convoluted tubule, the loop of Henle,
and the distal convoluted tubule, which
joins a collecting duct. The afferent
arteriole also connects with the distal
convoluted tubule, forming the
juxtaglomerular complex.
Bowman’s capsule
Items filtered out of the
blood into the
Bowman's capsule
– Glucose (but must be
returned to the blood by
active transport at the
loop of Henle)
urea
– salts
– water
–
Items that remain in the
blood are
–
–
–
–
RBCs
WBCs
platelets
large chemicals like
hormones
parts of the nephron &
functions 1
• Bowman's capsule. Force filtration in
Bowman's capsule causes much of the water
and ions and smaller molecules to leave the
blood and enter the proximal convoluted
tubule.
• The proximal tubule. the peritubular
capillaries contain blood in a hyperosmotic
state, so much of the water filtrate reenters
(reabsorption) the blood by osmosis. Active
transport also returns sodium (chloride
following passively), glucose, and amino acids
to the blood.
parts of the nephron &
functions 2
• The loop of Henle. The ascending loop actively
transports chloride ions (sodium ions follow
passively) into the surrounding area, recycling
salt and creating a hyperosmotic state in the
kidney medulla. The hypertonic state is
further increased by urea, which diffuses out
of the collecting ducts.
• The distal tubule. The active secretion of
sodium ions occurs with chloride ions and water
passively following. Potassium ions enter the
tubule.
parts of the nephron &
functions 3
• Collecting ducts. Water leaves the
collecting ducts in response to
antidiuretic hormone (ADH), which is
secreted by the posterior pituitary in
response to osmotic conditions in the
blood (actually detected by the
hypothalamus).
formation of urine
wastes - urine
The remaining wastes, now called
urine are transported out through
the collecting tubule to an area
known as the renal pelvis (a
collecting area) where the urine
then passes into the ureter
urinalysis
color
•pale yellow (straw)
•light yellow
•yellow
•green-yellow (olive)
•red-yellow
•red
•red-brown
•brown-black
•black
•milky
physical, chemical, microscopic
examination of urine
turbidity
(cloudiness)
Normally, freshly voided
urine is clear and
transparent. It may be cloudy
due to crystals and cells will
centrifuge out; bacteria will
not.
urinalysis
physical, chemical, microscopic
examination of urine
odor
Strong odors of urine need to be
identified because many can give
clues to the origin of diseases.
specific gravity
(density)
The refractometer measures
the refractive index of the total
soluble solids. When a beam of
light passes through one substance
into another, the beam is
refracted so that it travels in
another direction. The extent to
which the beam is refracted
depends on the concentration of
the total soluble solids.
urinalysis - urine odor
• Ammoniacal-Occurs especially during decomposition or urine on
standing ("alkaline fermentation") or retention within urinary
bladder; may be related to some bacterial infections.
• Effects of drugs and diet-Many ingested substances will give the
urine a distinct odor as ingested asparagus giving urine its
characteristic odor.
• Fecal-Due to contamination with feces or E. coli; often related to
bladder-GI tract fistula.
• Fetid or Putrid-May be caused by diseases of the GU tract.
Decomposition of urine containing cystine or pus will have the odor of
rotten eggs (H2S).
• Fruity or Sweetish-Usually due to acetone in diabetic acidosis,
starvation or dieting.
• Urinoid or Faintly Aromatic; Normal Attributed to volatile organic
acids most marked in "concentrated" urine specimens.
control of nephron
Nephron control is hormonal, with water
reabsorption controlled by ADH from the
posterior pituitary and sodium chloride
reabsorption controlled by aldosterone from
the adrenal medulla. Sodium chloride
transport is monitored by the juxtaglomerular
complex. The arteriolar cells secrete renin,
which stimulates the adrenal cortex to secret
aldosterone.
Aldosterone increases the absorption of
sodium chloride and the excretion of
potassium.
a few disorders of the
excretory system
Obstructive disorders
kidney stones
kidney cancer
Renal failure - (kidney failure)
UTIs - urinary tract infections, often caused
by gram-negative bacteria
cystitis-bladder infections
urethritis-inflammation of the urethra
pyelonephritis- inflammation of the
kidneys
kidney stones
• Cause - metabolic disorder involving calcium,
proteins and uric acid the build up of these
substances into a large deposit (stone)
• Symptoms - irritation of the urinary tract,
bleeding in the urinary tract, in cases with
large stones there can be extreme pain as
the stone(s) try to pass through the tract
• Treatments - removal by surgical means,
breakdown of stones by either physical
(ultrasound) or chemical means, dietary
changes to reduce chances of stones
renal (kidney) failure
• Causes - infections, trauma, diabetes,
tumors
• Symptoms - build up of toxins in the
blood stream (urea), jaundice, fatigue
• Treatments - dialysis, drug therapy,
transplants
bladder infections
• Causes - infection of the urinary tract
• Symptoms - burning sensation in the
flanks that can move down from the
middle of the back towards the front of
the groin, burning sensation while
urinating
• treatments - antibiotics
the excretory system
speaks…
Roses are red
Violets are blue
I clean out the systems
That's what I do
Violets are blue
Roses are red
Without the excretory system
We'd all be dead!
by John H.
Human Reproductive System
If it wasn't for me
You wouldn't be
I've kept population through many
a day
So the human race will stay
by Joey F.
Human Reproductive System
The reproductive system is the system
that allows for the continuation of the
human species
This system is different in males and
females
Human Reproductive System
The role of the male’s reproductive
system is to manufacture sperm and
then to deliver them to the female’s
reproductive tract where fertilization
may occur
Human Reproductive System
The role of the female’s reproductive
system is basically the same except
that it goes further if the sperm
meets an egg.
If fertilization occurs the female
reproductive system is designed to
nurture and care for the cell that will
soon grow into a baby
Human Reproductive System
• The sperm is produced in the male testis
and then travels through a series of
ducts to reach the body exterior
• The eggs are produced in the ovary of a
female. When a egg is to be expelled or
ovulated a “blister forms on the exterior
of the ovary. When the “blister” bursts
the egg may be collected by the ends of
the fallopian tubes and travels through
the fallopian tubes where it can be
fertilized by a single sperm
Human Reproductive System
• If an egg is fertilized it travels down
into the uterus where it embeds in the
wall of the uterus.
• There it divides rapidly and the cells
begin to specialize into the different
organs of a pregnancy. Some of the
cells form the amniotic sac while some
form the placenta and the umbilical
cord.
• Only a small number of these cells will
eventually form the fetus
Human Reproductive System
The scrotum and penis are the
male genitalia. The male
gonads, called testis, are tightly
coiled tubes surrounded by
tissue. Sperms develop in these
tubes. The male gonads are
located outside of the body
since sperm productions can only
occur at about two degrees
Celsius lower than normal body
temperature. After the sperm
are produced they mature and
are stored in the epididymis.
male reproductive system
The male reproductive
system also contains
three glands that add
secretions to the
semen.
seminal vesicles
prostate gland
bulbourethral glands
seminal vesicles
Sixty percent of semen is secreted
by the seminal vesicles. They lie
behind and below the bladder and
empty directly into the ejaculatory
duct. The fluid secreted is clear and
thick. It contains mucus, amino acids,
and fructose. The fructose provides
energy for the sperm.
prostate gland and
bulbourethral glands
• The prostate gland surrounds the
beginning of the urethra in which it
secretes its products. Prostatic fluid is
milky, thin, and alkaline in order to
balance the acidity of any urine
remaining in the urethra and the acidity
of vaginal fluids
• Bulbourethral glands lie along the urethra
below the prostate. Although their
specific function is still unknown, they do
secrete a viscous fluid before ejaculation
male reproductive system
Three layers of spongy tissue
comprise the human penis.
When sexually aroused, this tissue
fills with blood from the
arteries, while the veins are
sealed. This produces an
erection.
The shaft of the penis is covered
in relatively thick skin. The
head, or glans penis, is covered
with thinner skin. This results
in extra sensitivity in the glans
penis area.
Human Reproductive System
Ovaries, the female gonads,
are located below the
digestive system in the
abdominal cavity. Inside
each ovary are many follicles
which consist of a single egg
cell and one or more layers
of follicle cells. Follicle cells
protect and nourish the egg
cells. A woman is born with
about 400,000 follicles and
cannot produce more.
Human Reproductive System
Ovulation is the process in
which an egg is expelled from
a follicle. The egg is expelled
directly into the abdominal
cavity and is picked up by the
fallopian tubes. Inside the
fallopian tubes are cilia which
sweep the egg toward the
uterus. At the neck of the
uterus is the cervix followed
by the vagina which has very
thin walls, much thinner than
those of the uterus.
Human Reproduction
Before fertilization can occur,
the sperm must reach the
egg. Each egg is only viable for
12 to 48 hours and some sperm
can survive for as long as 72
hours, but most can only retain
their fertilizing power for 12
to 48 hours. Therefore in
order to produce offspring,
sex must occur no more than
72 hours before ovulation or no
later than 24 hours after.
Human Reproduction
• The moment of ejaculation, millions of sperm are
released into the female’s reproductive
tract. Many are able to swim up through the
vagina towards the cervix. Many are killed by
the acidity of the vaginal fluids. Here
thousands of sperm are killed by phagocytes
which recognize them as “non-self.” Of the
millions of sperm that are ejaculated, only a few
thousand are able to reach the egg.
Human Reproduction
• Should sperm reach the egg, they cannot
immediately fertilize it. As time must pass for
their membranes to become capacitated, or
weakened. This is facilitated by the cervical
mucus, and in the following 6-8 hours the sperm are
gradually capacitated.
• After capacitation has occurred, the acrosomal
reaction follows. This reaction releases enzymes in
the area surrounding the egg therefore weakening
the intracellural cement that surrounds the
egg. Once weakened a single sperm is allowed to
penetrate the egg and fertilize it.
STD’s in USA
references
• Cyber-Anatomy Web site
http://library.thinkquest.org/11965/cyberanatomy_index.html
cirrhosis of the liver
• Causes - excessive intake of alcohol over
a extended period of time which causes
an impairment of liver functions
• Symptoms - elevated temp., weight loss,
indigestion
• Treatments - drug therapy, blood
transfusion, transplants