Unit 6: Digestive System
Define the digestive system (pg.656)
Name the structures included in the alimentary canal.
Histology overview- These four layers (tunics) are present in all areas
of the digestive tract. (Discuss each)
a. mucosa -
b. submucosa -
c. muscular layer -
d. serosa -
I. Anatomy and Hostology of the Digestive Tract
Digestion begins in the oral cavity: (2 types of digestion)
mechanical & chemical
A. Structures involved in oral cavity (pg.658):
mouth -
cheeks -
lips -
hard and soft palates (pg.660) -
vestibule -
uvula -
B. Accessory organs -
1. Tongue (discuss) -
used in 1) mastication
2) deglutition
3) taste and speech
**Define each:
a. Frenulum (frenum) -
b. Hyoid bone -
c. Papillae (wait until lecture) -
filliform -
fungiform -
vallate -
foliate -
2. Discuss Teeth (pg.661) -
Two sets in mammals:
deciduoud (primary) -
permanent (secondary) -
a. Types and numbers: (pg.662-663)
NAME deciduous # Permanent # Function
incisors
cuspids (canine)
bicuspids (premolar)
molars
Total number
b. Tooth Structure: (draw and label figure 17.10 and include the
function og these parts)
Tooth cells (wait until lecture):
Ameloblasts -
Odontoblasts -
Odontoclasts -
What are dental caries? How can they be prevented? (pg.664)
3. Discuss Salivary Glands (pg.665) -
a. Salivary Secretions
(glands contain 2 types of cells):
1. serous cells (discuss) -
* Salivary Amylase (ptyalin)
2. mucous cells (discuss) -
b. Discuss Major Salivary Glands:
- Parotid
- Submandibular
- Sublingual
c. Functions (wait until lecture):
II. Discuss Pharynx (throat) (pg.666) -
A. Sections (discuss each):
1. nasopharynx -
2. oropharynx -
3. laryngopharynx -
B. Openings (wait until lecture):
C. Lymphatic tissue (wait until lecture);
D. Functions (wait until lecture):
1)
2)
3)
E. Epiglottis: cartilage covered with epithelial tissue
location: dorsal to tongue
III. Discuss Esophagus (pg.667) -
A. Structure - 2 layers of muscle
longitudinal = outer
circular - inner
B. Function (wait until lecture)-
C. Cardiac Sphincter -
IV. Stomach (pg.670) -
Function (wait until lecture) -
Location (wait until lecture) -
Parts of the Stomach:
1) 3 regions (discuss each):
FUNDUS -
BODY -
PYLORUS -
2) Pyloric Sphincter
3) Greater & Lesser Curvature (wait until lecture)
STRUCTURE (wait until lecture):
Serous Coat & Peritoneum
4) Gastric Secretions (pg. 670):
A. Gastric mucosa (wait until lecture) -
Gastric pits -
Gastric glands -
3 types of cells found on gastric glands (discuss in detail):
1. Mucous cells (pg.671)-
2. Chief cells -
3. Parietal cells -
B. 1) Discuss Pepsinogen -
2) Discuss Pepsin -
*Pepsin is a gastric protease
3) Gastric lipase -
4) Intrinsic factor -
Describe the contents of gastric juice (table 17.50) -
C. Regulation of Gastric Secretions (pg.672) -
1) Cephalic (Psychic) Phase:
2) Gastric Phase:
Gastrin -
D. Gastric Absorption (pg.673) -
E. Ulcers (wait until lecture)
Peptic Ulcer -
Gastric Ulcer -
Duodenal Ulcer -
Enzymes
1. Enzymes (pg.51) -
Substrate (pg.104) -
A. Names (wait until lecture) -
Amylase=
Protease=
Lipase=
B. Formation (wait until lecture) -
C. Reactions (pg.102)-
Metabolism -
Catabolic -
Anabolic -
D. Each enzymes has specificity (pg.104).
E. Enzymes are affected by (pg.105) -
F. Functions in Digestive System (wait until lecture):
Source Secretion Substrate End Products
G. Extracellular vs. Intracellular
(wait until lecture)
Protein Synthesis
1. Amino acids are the ingredients used to make proteins and are located
in the cytoplasm of the cell.
2.
3. DNA is too large to leave through the nuclear membrane.
4.
5. This m-RNA passes into the cytoplasm and attaches to ribosomes.
6.
7. t-RNA brings amino acids to the m-RNA on the ribosome and attaches them
in sequence according to the code on m-RNA (copied from DNA).
The linked-together amino acids leave the ribosome and m-RNA and are
now a protein ---------- used for:
1.
2.
3.
Why We Eat
Nutrition - the study of nutrients, sources and how they are used.
1. Nutrients -
A. Examples:
1. Carbohydrates -
sources -
uses -
2. Lipids -
sources -
3. Proteins -
sources -
uses -
B. Energy - may be obtaind from carbohydrates, lipids and proteins
1. Calorie -
2. Energy requirements depend on:
a. BMR (pg.870)-
b. muscular activity -
c. thermic ffect of food (maintaining body temperature) -
3. Recommended Calorie intake:
male -
female -
4. Energy balance -
5. Terms:
overweight -
obesity -
C. Vitamins -
Two categories:
1. fat soluble -
2. water soluble -
* You must know functions, sources, and results from deficiencies for:
vitamin A, D, K, C (ascorbic acid)
Vitamin defeciency:
1. Low intake -
2. Failure to absorb -
3. Liver doesn't store -
D. Minerals
Functions-
Most common minerals-
Lecture 1