Digestive, Urinary &
Reproductive Systems
Honors Physiology
Tamalpais High School
The Digestive System
I. System Function
•
The digestive system
mechanically and
chemically breaks down
food and absorbs the
products.
II. System Structures
•
The digestive system
consists of an alimentary
canal and several
accessory organs.
Fig. 17.1
The Digestive System
III. The Alimentary Canal
Fig. 17.2
The Digestive System
III. The Alimentary Canal
A. Wall Layers
1. Mucosa
Structure: composed of
epithelial, connective, and
smooth muscle tissue; mucus
secreting glands present
Function: protection,
absorption, secretion
2. Submucosa
Structure: composed of loose
connective tissue; glands, blood
and lymph vessels present
Function: nourishment
Fig. 17.3
The Digestive System
III. The Alimentary Canal
A. Wall Layers
3. Muscular layer
Structure: 2 layers of smooth
muscle; circular and
longitudinal shaped fibers
Function: movement
4. Serosa
Structure: composes the outer
layer of the canal
Function: secretion of fluid to
lubricate so tube can slide freely
The Digestive System
B.
The Oral Cavity
1. mechanical digestion:
teeth & tongue
Fig. 17.5 & 17.11
2. Chemical digestion:
salivary glands, amylase
(starch)
The Digestive System
C. The Pharynx
1. Epiglottis
Fig. 17.14
The Digestive System
D.
The Esophagus
1. peristalsis
Fig. 17.15
The Digestive System
E. The Stomach
1. Mechanical Digestion: grinding
2. Chemical Digestion: HCl, pepsin (proteins), lipase (fat)
Fig. 17.17
The Digestive System
F.
The Small Intestine
1.
Chemical Digestion: Several enzymes break down protein,
carbohydrates, fat, and nucleic acids (DNA & RNA)
2.
Nutrients absorbed into the bloodstream
Fig. 17.35
The Digestive System
G.
The Large Intestine
1.
No digestion
2.
Water reabsorbed here, waste storage & elimination
Fig. 17.43
The Digestive System
IV. Accessory Organs
A. Liver
1. Creates bile
B. Gallbladder
1. Stores bile
Fig. 17.26
The Digestive System
C. Pancreas
1. Several digestive enzymes dumped into the small intestine
Fig. 17.23
The Urinary System
Fig. 20.1
The Urinary System
I. Overview of the Urinary System Organs
A. Kidneys
Function: Homeostasis
•
maintain the chemical make-up of the blood
 balance of water, salts, acids and bases
Function: Excretion
•
filters and excretes “bad” stuff
 toxic nitrogen compounds
 ingested compounds (drugs, etc)
The Urinary System
B. Urinary Bladder
 storage and voiding of
urine
 stretchy smooth
muscle walls
C. Ureters and Urethra
 smooth muscle urine
transportation tubes
 peristalsis
The Urinary System
II. Kidney
A. Macroscopic Anatomy
Protective layers:
renal capsule and adipose
tissue
Internal Anatomy: Three distinct
regions:
Cortex
Medulla
Pelvis
Fig. 20.4
The Urinary System
B. Microscopic Anatomy
nephron
Figs. 20.4 & 20.6
The Urinary System
 Renal corpuscle
 glomerulus
 glomerular/Bowmans
capsule
 Proximal convoluted
tubule
 Nephron loop (loop of
Henle)
- descending limb
- ascending limb
 Distal convoluted tubule
 Collecting duct system
Figs 20.6 & 20.8
The Urinary System
III. Urine Formation
Three Major Processes:

Filtration, Reabsorption, Secretion
The Urinary System
A. Filtration
- in the cortex
- blood is filtered from capillaries of the
glomerulus into the glomerular capsule.
 membranes act as strainers
 permit passage of smaller molecules (glucose,
N waste, water) but restricts blood cells and larger
proteins
 pressure gradient
The Urinary System
B. Reabsorption
- cortex and medulla
 Most in the PCT
 Some in the loop of Henle
(H2O) and DCT
 “Good” small molecules
return to the blood.
glucose, sodium,
potassium, water
 Molecules not reabsorbed
includes: urea, creatinine,
uric acid
 99% of original filtrate is
eventually reabsorbed.
The Urinary System
C. Secretion
Cortex and medulla
The PCT, DCT and
collecting ducts
“Bad” substances that were not filtered move into
the nephron by active transport
Substances include:
toxic by-products, drugs, non-natural molecules
The Reproductive System
I. The Male Reproductive System
Fig. 22.4
The Reproductive System
II. Spermatogenesis




Fig. 22.9
Production of male
gametes (sperm)
A healthy, adult male
makes about 400
million sperm a day!
Sperm are made in the
seminiferous tubules in
the testes
Testosterone is made
by the interstitial cells
in the testes
The Reproductive System
III. The Female Reproductive System
Fig. 22.19
The Reproductive System
IV. Oogenesis
 The process which leads
to the production of
female gametes (eggs)
 The ovarian cycle
produces one egg every
28 days
 The corpus luteum
produces progesterone
 The follicle cells produce
estrogen
Fig. 22.26
The Reproductive System
The Reproductive System