Notesale: Turn your study into money

Document Preview

Extracts from the notes are below, to see the PDF you'll receive please use the links above

---

CLASS 11
GIT

#NUTRITION
-getting and utilization of energy rich nutrients (food) by an organism
...

-provides energy for life activities
Li-provides materials for growth
- maintains body temperature
-repairs tissues
...

#HUMAN DIGESTIVE SYSTEM
I
...

B)BUCCAL CAVITY
-oral or mouth cavity
-Consists of palate (roof), teeth & muscular tongue
...

- Tongue is a muscular organ attached to the floor of oral cavity by the frenulum
...

- Some papillae bear taste buds
...

C)PHARYNX
- Common passage for digestive and respiratory systems
...

@Cough during swallowing is due to improper movement of epiglottis *
D)OESOPHAGUS
- Muscular
-30 cm
-conducts food into stomach

- Posterior part has gastro-oesophageal
sphincter (a circular muscle)
...

D)STOMACH
- ‘J’ shaped structure
-for storage and digestion of food
...

- Inner wall of stomach bears rugae (longitudinal folds)
...
5 cm diameter
- Consists 3 parts,
1)duodenum-C shaped first part
2)Jejunum-middle part
3)Ileum-terminal part
@Ileum is highly coiled structure*
- Finger-like villi are seen at the mucosa
...

@Lacteals are present in ileum*
F)LARGE INTESTINE
- 1
...

-@Certain symbiotic microorganisms reside in caecum*
- The colon consists of ascending colon, transverse colon,descending colon and Sigmoid colon
...

- In some herbivores, the large intestine consists of several cellulose digesting bacteria
...

@Human dentition is Thecodont, Heterodont & Diphyodont*
1)THECODONT
It means teeth are placed in the jaw sockets
...

-They are
A)incisors (I) for cutting
B) canines (C) for tearing
C)premolars (PM) & molars (M) for mastication
...

3)DIPHYODONT
-It means teeth appeartwice in the
lifetime
-They are milk (deciduous) teeth and permanent teeth
...

@Primary dentition differs from permanent dentition in not having-Premolars*
-Last 4 molars (wisdom teeth) appear only at the age of 18
...

@Enamel of tooth is secreted by ameloblast cells*

#DENTAL FORMULA
-It explains the kinds and number of teeth
@Human dental formula (of permanent teeth):
ICPM=2123/2123*
-Dental formula of milk dentition:
#HISTOLOGY OF HUMAN GUT
Human gut is formed of 4 layers:
1
...
-Contains secretory and absorptive cells
...
SUBMUCOSA
-Soft connective tissue layer just outside the mucosa

-Nerves and blood vessels are present
...
MUSCULARIS
-Outer to submucosa
-Smooth muscle layer(inner circular & outer longitudinal)
...
SEROSA
Outermost fibrous layer
...

- They include salivary glands, gastric glands, intestinalglands, pancreas & liver
...

@Stenson’s duct-Duct of parotid gland opening into vestibule *
B)Submaxillary/submandibular
-2
-Seen in lower jaw
...

FUNCTION OF SALIVARY GLANDS
- Salivary glands secrete saliva
-saliva contains
1)99
...

2)GASTRIC GLANDS
Tubular glands found on the inner wall
...

B)CHIEF(ZYMOGEN OR PEPTIC)CELLS
-Secrete proenzymes like pepsinogen & prorennin and some lipase
...

-Gastric glands secrete acidic (pH 1
...
0) gastric juice
...
2 - 1
...

- Situated in abdominal cavity, just below the diaphragm
...
-They secrete
alkaline bile juice
...

- Bile has no enzymes but contains bile pigments (bilirubin & biliverdin), bile salts, cholesterol
and phospholipids
...

- It is a cream-coloured heterocrine gland, i
...
it has both exocrine and endocrine parts
...

-*Sphincter of Oddi is present at junction of hepato-pancreatic duct and duodenum*
- Exocrine partsecretes alkaline pancreatic juice
...


-*Islet of langerhans are present in pancreas*
5)INTESTINAL GLANDS
- Simple tubular glands
...
CRYPTS OF LEIBERKUHN
@Crypts of leiberkuhn are intestinal glands*
-Consists of mucus-secreting
Goblet cells and enzyme-secreting Paneth cells
...
BRUNNER(DUODENAL)GLANDS: @Brunner's glant are present in submucosa of
duodenum*
...

- The bicarbonate and mucus provide alkaline medium and protect intestinal mucosa
...
E
...

A)Gastrin
-Stimulates gastric glands to secrete HCl and
pepsinogen
...

C)Cholecystokinin (CCK)
-Stimulates secretion of bile from gall bladder and pancreatic enzymes from pancreas
...

-Several other non-endocrine tissues secrete hormones called
growth factors
...


A)DIGESTION IN BUCCAL CAVITY
-@Salivary gland secretion does following functions1)control bacterial population in mouth
2)digestion of complex carbohydrates (only polysaccharides not disaccharides 3)lubrication of
oral cavityOnly starch digestion*
-About 30% of starch is digested by ptyalin
-Nucleotides Nucleotidase Nucleosides
Nucleosides Nucleosidase Sugars + Bases
Diglycerides, monoglycerides Lipases Fatty acid + Glycerol
#In large intestine, there is no significant digestive activity
...
Absorption of water, minerals and certain drugs
...
Secretes mucus for adhering waste (undigested) particles
Starch Salivary amylase
pH 6
...

Fully digested semi fluid and alkaline food formed in small

B)DIGESTION IN STOMACH
-Stomach stores food for 4-5 hrs
-It is mixed with gastric juice by the churning movements and is converted into acidic pasty form
(chyme)
Pepsinogen (inactive)
HCl
Pepsin (active)
Protein
Pepsin
Proteoses + Peptones (peptides)
Prorennin (inactive)
HCl Rennin (active)
intestine is called chyle
...


C)DIGESTION IN SMALL INTESTINE
-in Duodenum Chyme is mixed with succus entericus, pancreatic juice & bile jujuice
...

Starch Amylopsin Maltose + Isomaltose + limit dextrins
Enterokinase (Enterokinin) secreted by intestinal mucosa
activates trypsinogen to active trypsin
...

Trypsinogen
Enterokinin
Trypsin
Chymotrypsinogen
Trypsin
Chymotrypsin
Procarboxypeptidase Trypsin Carboxypeptidase
concentrated region without the expenditure of energy
...

@Carboxypeptidase requires zinc for its activity*
@Trypsinogen is constiuent of pancreatic juice whic is poured directly into duodenum *
#ABSORPTION OF DIGESTED PRODUCTS
Casein (milk protein) Rennin
Paracasein
Paracasein
Ca2+

Ca paracaseinate (curd)
Calcium paracaseinate Pepsin Peptones
Only in
infants
Absorption is the transfer of end products of digestion
through the intestinal mucosa into blood & lymph
...

a) PASSIVE ABSORPTION(Passive transport): Absorption of
nutrients from higher concentrated region to lower
The gastric lipase hydrolyses a small amount of lipids
...
SIMPLE DIFFUSION
- In this, molecules alone can be
diffused
...
g
...

ii
...

-E
...
glucose, amino acids etc
...
e
...

-It needs energy
...
g
...

ABSORPTION OF LIPIDS
- Monoglycerides, diglycerides and fatty acids cannot be absorbed directly as they are insoluble
in water
...

Proteoses
Carboxypeptidase
- They are reformed into small protein coated fat globules
Fats Lipases Diglycerides Lipases Monoglycerides
Nucleic acids Nucleases Nucleotides

c) ACTION OF INTESTINAL JUICES
-At duodenum region, the
intestinal enzymes act on the products of above reactions
...
They are transported into lacteals in the
villi
...


#
ABSORPTION IN ALIMENTARY CANAL
• MOUTH
- Certain drugs
...

SMALL INTESTINE
-mainly Jejunum & Ileum
-All nutrients including minerals & vitamins
...

• LARGE INTESTINE
-Water, some minerals & drugs
...

- It is called assimilation
...
form faeces
...

-Faeces are temporarily stored in rectum and are eliminated through anus
...

#-

- Heat is the ultimate source of all energies
...

- Its unit is calorie (cal) or joule (J)
...

- This value is tiny amount of energy
...

- One kilo calorie is the amount of energy required to raise the temperature of 1kg of water by
1o
C
...

- Actual amount of energy combustion of 1g of food is the
physiologic value of food
...
1 kcal/g
4
...
65 kcal/g
4
...
45 kcal/g
9
...

2)VOMITTING
-Ejection of stomach content through mouth
-controlled by medulla oblongata
...

5)INDIGESTION
-Condition leading to feeling of fullness -due to improper digestion
@due to anxiety, inadequate enzyme secretion, food poisoning, spicy food*
6)PEOTEIN ENERGY MALNUTRITION (PEM)
-It is the dietary deficiencies of proteins & food calories
...

A)MARASMUS
-due to deficiency of both proteins and
calories
-found in infants less than a year in age
@Marasmus occurs due to Replacement of mother’s milk by foods with poor proteins and
caloric value*
-often happens if mother has second pregnancy or child birth when the older infant is still too
young
...

B)KWASHIORKOR
@kwashiorkor is only protein deficiency disorder*
-Reason: Replacement of mother’s milk by a high calorielow protein diet in a child more than
one year in age
-Symptoms:
$ Like marasmus, it shows wasting of muscles,thinning of limbs, failure of growth & brain
development
...

@Pt of Kwashiorkor is advised to eat more meat,lentils,milk and eggs in diet*
Note@High cholesterol patients are advised to use groundnut oil,margarine and vegetable oil*



---