Transcript Chapter 20: Digestive System

Chapter 20: Digestive System
Chapter 21: Urinary System
Functions of Digestion
Ingest food
 Break down food in to small molecules:



Mechanical digestionChemical digestion –
Absorption
 Elimination

Carbohydrates
Include sugars and their polymers
 Monomer is the monosaccharide
 Include 3 – 7 carbons with the –OH
group being present on each carbon
except one, which is double bonded
to an oxygen (carbonyl group)

Lipids
A group of polymers that have one
characteristic in common, they do
not mix with water. They are
hydrophobic.
 Some important groups are fats,
phospholipids, and steroids.

Enzymes



Increase speed of
chemical reactions catalyst
A protein
Can change shape if
conditions are not
favorable.
Alimentary Canal

Hollow tube that begins at the mouth, ends
at the anus







Mouth
Pharynx
Esophagus
Stomach
Small intestine
Large intestine
Rectum
A. Mouth



•
Forms a bolus
Chemical digestion –
mucous, amylase
(break down carbs)
Mechanical
digestion: chewing
Roof of mouth:


Hard palate
Soft palate
Tongue and Taste


Lingual frendulum –
attaches tongue to
floor of mouth
Taste buds:

Papillae: elevations
on tongue
Salivary Glands




Saliva – water
mucous, amalase
Parotid – front of
and below ears.
(mumps)
Sublingual
submandibular
B.Pharynx
Region between mouth and esophagus
 “throat”
 Function – swallowing
 Epiglottis – blocks larynx
 Uvula – back of throat

C. Esophagus
3.
4.
5.
Lined by mucous
membrane and
smooth muscle
Peristalsis –
involuntary
contraction of
esophagus
Heartburn – (acid
reflux)
Esophagus Continued
D. Stomach



Stores food and
digests protein
Rugae – folds
inside stomach
Ulcers
Stomach Continued

Gastric Juice – produces
Chyme





Pepsin – enzyme that
digests protein
HCL – kills bacteria,
breaks down food,
Intrinsic factor –
absorption of B12.
Mucous – softens food
Gastrin – hormone that
causes gastric juice to be
released.
E. Small Intestine
Function- receives secretions from the
liver, pancreas and absorption of
nutrients.
 Lined with Villi – furry looking,
absorption, increase surface area

F. Large Intestine


Function – absorb
water, produce
feces
E.coli bacteria
present
Disorders of Large Intestine
Diarrhea –
 Constipation –
 Appendicitis –
 Diverticuloisis – colon cancer


Colonoscopy
Part 2: Digestive System
Accessory organs – food does not
pass through
1. Pancreas

Secretes Sodium Bicarbonate and
enzymes to digest carbohydrates,
proteins, and fats
2. Liver – Largest gland






Storage of glucose as
glycogen
Destruction of old red
blood cells – this
creates bilirubin
Production of bile
Plasma proteins
Detoxification of blood
Storage of iron and
other vitamins
Liver Lobule Anatomy


Functional unit of
the liver.
Blood travels from
small intestine –
hepatic portal vein –
to various liver
lobules.
3. Liver Disorders

Hepatitis – inflammation of the liver due
to contaminated drinking water, sexual
transmission, or blood transfusion
Cirrhosis of liver

Cirrhosis – chronic
disease due to
excessive amount of
alcohol. Liver
becomes fatty
tissue.
Jaundice

Jaundice – yellowish
tint due to large
amounts of bilirubin
in blood.
C. Gallbladder

Storage of bile – emulsifies fats and
neutralize acids
Chapter 21
Excretory system
Structures of Urinary System




1. 2 kidneys
2. 2 ureters – tube
that leads to bladder
3. Bladder – stores
urine
4. Urethra – tube
for eliminating urine
Structure of Kidney





Renal cortex – outer
layer, filtration
Renal medulla –
middle layer, filtration,
absorption
Renal pelvis – urine
collection and transport
Renal artery Renal vein -
Functions of Kidney
I.
Kidney Function – filter blood that has
collected wastes from cells.






A. Excrete waste – urea, uric acid, creatine,
ammonium
B. Maintain blood volume – regulating water
excretion
C. monitor electrolytes in blood
D. monitor blood pH
E. secrete Renin – enzyme to help maintain
blood pressure
F. stimulates red blood cell production
Lipids
A group of polymers that have one
characteristic in common, they do
not mix with water. They are
hydrophobic.
 Some important groups are fats,
phospholipids, and steroids.
