1. Phylum
    2. 1. Classification of Animals
    2. Protozoa
    3. Porifera
    4. Coelenterata
    5. Platyhelminthes
    6. Nemathelminthes
    7. Annelida
    8. Earthworm
    9. Arthropoda
    10. Cockroach
    11. Mosquito
    12. Honey bee and Silk moth
    13. Mollusca
    14. Echinodermata
    15. Hemichordata
    16. Chordata
    17. Pisces
    18. Amphibia
    19. Frog
    20. Reptile
    21. Aves
    22. Mammalia
    23. Rabbit bone
  2. Animal Behaviour and Adaptation
    3. 24. Animal behaviour
    25. Animal adaptation
    26. Migration
  3. Developmental Biology
    4. 27. Development of Animals
    28. Development of Frog
  4. Human Biology
    5. 29. Tissues
    30. Sense organs
    31. Digestive system
    32. Circulatory system
    33. Respiratory system
    34. Nervous system
    35. Endocrine system
    36. Reproductive system
    37. Excretory system
    38. Skeletal system
    39. Basic concept of Immunology
    40. Human diseases
  5. Evolutionary Biology
    6. 41. Origin of Life
    42. Organic Evolution
    43. Theories of Evolution
    44. Evolution of Human beings
    45. Horse Evolution
Human Biology
31. Digestive system
ANATOMY OF DIGESTIVE SYSTEM
Image 1
Fig. Digestive System of Human being
Alimentary canal
Mouth
Image 1
Credit. The PMFA journal
Image 2
Credit. YA Class
▢ Lips:
❖ Upper lip:
◉ Philtrum:
  1. It is the depresseion in upper lip.
◉ Vibrissae/ Whiskers:
  1. Hair present in upper lip of Rabbit.
  2. Used to sense the movement.
❖ Lower lip:
Note
Lips are absent in frog.
Oral cavity
Image 1
Fig. Buccal cavity
Credit. National Cancer Institute
▢ Vestibule: Space between the lips, cheeks, gums and teeth.
▢ Oral cavity proper/ Buccal cavity:
❖ Lining: Stratified Squamous epithelium
❖ Roof:
◉ Palate:
◈ Hard palate:
◈ Soft palate:
■ Uvula/ Velum:
  1. Posterior hanging part of soft palat.
  2. Moves upward during swallowing.
❖ Floor:
◉ Teeth:
◉ Tongue:
❖ Posterior side:
◉ Tonsils:
◈ Pharngeal/ Adenoid tonsil:
◈ Lingual tonsil:
◈ Palatine tonsil:
Note
  1. Tonsils are lymphoid organs.
  2. They are arranged in ring like pattern called as Waldeyer's ring.
Oesophagus
Stomach
▢ Cardiac part:
❖ Fundus:
❖ Body:
▢ Pyloric part:
❖ Pyloric canal:
❖ Pyloric antrum:
Small intestine
Duodenum
Jejunum
Ileum
Appendix
Large intestine
Colon
Ascending colon
Transverse colon
Descending colon
Sigmoid colon
Rectum
Anus
Accessory organs
Teeth
▢ Study of teeth: Dentistry or Odontology
▢ Origin of teeth:
❖ Ecto-mesodermal:
  1. Enamel &rarr Ectoderm
  2. Rest &rarr Mesoderm
▢ Parts of teeth:
❖ Crown: Projecting above the gum.
❖ Neck: Between the crown and root.
❖ Root: Embedded in the jaw beneath the gum.
▢ Structure of teeth:
❖ Enamel:
  1. White and shining part of teeth
  2. Hardest substance of Human body due to present of Fluorine
  3. Richest in calcium salt.
  4. Produced by ameloblast or amyloblast.
❖ Dentine:
  1. Hardest tissue of human body.
  2. Produced by odontoblast.
❖ Pulp cavity:
  1. Cavity of teeth.
  2. Filled with connective tissue, blood vessels, nerves and lymphatics.
  3. Lined by odontoblast.
❖ Cementum:
  1. Present between teeth and gums.
❖ Periodontal membrane:
  1. Holds the root in socket.
▢ Types of teeth:
❖ On the basis of Shape:
Name of teeth
Number in each quadrant
Uses
Special
Incisor
2
Cutting and shearing food
Tusks of Elephant is Modified Incisor.
Canine
1
Gripping and tearing food
  1. More developed in carnivores
  2. Tusks of walrus is modified canines.
Premolar
2
Crushing and grinding food
Molar
3
Crushing and grinding food
  1. The third molars appear very late, are non-functional in human and are called Wisdom teeth.
◉ notes:
  1. Frangs of snakes are modified maxillary teeth.
❖ On the basis of Appearance in life:
Name of teeth
Appearance
Examples
Monophyodont
Once in life
  1. Premolar and last molar of man
Diphyodont
Twice in life
  1. Incisor
  2. Canines
  3. Molar
Polyphyodont
Many times in life
  1. Fish
  2. Amphibians
❖ On the basis of Position in Jaw:
Name of teeth
Position in Jaw
Examples
Thecodont
In Bony socket
  1. Man
  2. Crocodile
Pleurodont
On the lateral side of Jaw bone
  1. Reptile
Acrodont
On the terminal part of Jaw bone
  1. Fish
  2. Amphibians
❖ On the basis of Structure and Function:
Name of teeth
Appearance
Examples
Heterodont
Different types
  1. Mammal
Diphyodont
All teeth same type
  1. Incisor
❖ On the basis of Crown:
Name of teeth
Characteristic
Examples
Secodont
Canine teeth become long and pointed and bend backwards.
  1. Canine teeth of carnivorous animals
Hypsodont
Crown part is large and root is small or absent.
  1. Incisor
  2. Canines
Brachyodont (Cheek teeth)
Crown part is small and root is long.
  1. Premolar
  2. Molar
❖ On the basis of Lophs:
Name of teeth
Lophs shape
Examples
Lophodont
  1. Large
  2. Wide
  3. Flat
  1. Rabbit
  2. Elephant
Bunodont
  1. Small
  2. Spherical
  1. Humans
Solenodont
  1. Large
  2. Semilunar
  1. Ruminant animal
Carnessial
  1. Long
  2. Pointed
  1. Carnivorous animals
▢ Dental formula:
❖ Milk/temporary teeth in man:
◉ Dental formula: \(\frac{2102}{2102}\)
❖ Permanent teeth in man:
◉ Dental formula: \(\frac{2123}{2123}\)
❖ Teeth in rabbit:
◉ Dental formula: \(\frac{2033}{1023}\)
Tongue
▢ Parts:
❖ Papillary part:
◉ Location: Anterior 2/3 part of the tongue
◉ Papillae:
◈ Circumvalate papillae/ Valate papillae:
  1. Largest papillae.
  2. Least in number.
◈ Fungiform papillae:
  1. Mushroom shaped.
◈ Filliform papillae:
  1. Thread like.
  2. Taste buds are absent.
◈ Foliate papillae:
  1. Vestigial in human.
❖ Pharyngeal part:
  1. Posterior 1/3 part of the tongue.
▢ Taste areas:
  1. Salt and sweet &rarr Tip
  2. Sour &rarr Side
  3. Bitter &rarr Back
  4. Umami &rarr Taste of meat
Digestive glands
Salivary glands
Salivary glands
No.
Ducts
Location
Features
Parotid gland
1 pair
Stenson's duct
Beneath ears
  1. Largest salivary gland
  2. Compound tubulo-acinar gland
  3. Mumps is a viral disease by Paramyxovirus causing painful inflammation of parotid glands.
Sublingual gland
1 pair
Duct of Rivinus or Duct of Bartholin
Beneath tongue
  1. Smallest salivary gland
  2. Compound acinar gland
Submaxillary gland or Submandibular gland
1 pair
Wharton's duct
Jaw angles
  1. Compound acinar gland
Infraorbital gland or Zygomatic gland
1 pair
Beneath eye orbits
  1. Not in man, found in Rabbit
PHYSIOLOGY OF DIGESTIVE SYSTEM
Control of digestive system
Neural control
Hormonal control
Digestion process
Digestion of Carbohydrates
Digestion of Fats
Digestion of Proteins
Absorption process
Absorption of Carbohydrates and Proteins
Absorption of Fats
NUTRITION
Energy giving food
Carbohydrates
Fats
Body building food
Proteins
Protective food
Vitamins
Minerals
Dietary fibres
Water
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
16.
17.
18.
19.
20.
21.
22.
23.
24.
25.
26.
27.
28.
29.
30.
31.
32.
33.
34.
35.
36.
37.
38.
39.
40.
41.
42.
43.
44.
45.
46.
47.
48.
49.
50.
51.
52.
53.
54.
55.
56.
57.
58.
59.
60.
61.
62.
63.
64.
65.
66.
67.
68.