1. Digestive System β Introduction
Digestive System kya hai?
Food ko simpler substances mein break down karne ka process β nutrient absorption ke liye.
2. Mouth & Oesophagus
π Mouth (Oral / Buccal Cavity)
- Digestion yahan se start hoti hai.
- Teeth β food chew karte hain (mechanical digestion).
- Saliva (salivary glands se) β Salivary Amylase contain karta hai β starch (complex carbs) β simple carbs.
- Tongue food mix karne aur swallowing mein help karta hai.
π Pharynx & Oesophagus
- Pharynx: Mouth ko oesophagus se connect karta hai.
- Oesophagus: Length = 25 cm β muscular tube jo food ko stomach tak push karta hai peristalsis (wave-like movement) se.
3. Stomach
Stomach β J-shaped muscular organ
- HCl (Hydrochloric Acid): Germs kill karta hai, acidic medium provide karta hai. Gastric juice mein present (pH 1.6).
- Pepsin: Proteins digest karta hai β sirf acidic medium mein kaam karta hai.
- Mucus: Delicate stomach lining ko acid se protect karta hai.
- Sphincter Muscle: Food ko stomach se small intestine mein pass karne deta hai.
4. Small Intestine
Small Intestine β Longest part of alimentary canal
- Main site of digestion and absorption.
- 3 parts mein divided: Duodenum Jejunum Ileum
- Yahan liver se bile aur pancreas se pancreatic juice receive hoti hai.
5. Bile & Pancreas
π Bile (Bile Juice)
- Bile ek enzyme nahi β supporting role play karta hai.
- Alkaline (basic) in nature.
- Acidic food ko neutralize karta hai small intestine se pehle.
- Pancreatic + intestinal enzymes ke liye favorable pH create karta hai.
- Emulsification of Fats: Large fat globules β small globules.
π‘ Pancreas
- Function: Carbs, proteins aur fats digest karta hai.
- Amylase: Carbs break down.
- Lipase: Fats β fatty acids + glycerol.
- Trypsin: Basic medium mein kaam karta hai β Proteins β amino acids.
6. Large Intestine
Large Intestine β Length: 1.5 m
- Function: Remaining undigested food se water + electrolytes absorb karna β feces solidify β elimination.
- Cecum: Large intestine ka pehla part β small intestine ko colon se connect karta hai.
- Colon: Indigestible food residues se water absorb karna.
7. Liver
Liver β Human body ki sabse badi gland
- Glucose β Glycogen (storage) β process = Glycogenesis.
- Plasma proteins synthesize karta hai.
- Amino acid metabolism (deamination + urea formation).
- Blood sugar levels maintain karne ke liye glycogen store karta hai.
Kupffer Cells
- Star-shaped phagocytic cells β liver sinusoids ki lining mein.
- Old/damaged RBCs break down karte hain.
- Blood se pathogens + debris clean karte hain.
- Regenerative ability hoti hai.
Hepatocytes
- Liver ki main parenchymal (functional) cells.
- Carbs, proteins aur fats ka metabolism.
- Blood detoxification.
8. Villi, Rectum & Anus
Villi
- Small intestine ki inner wall pe finger-like projections.
- Surface area significantly increase karte hain.
- Nutrient absorption (assimilation) enhance karte hain.
Rectum
- Feces store karta hai.
Anus
- Opening jisse waste body se excrete hota hai.
9. Food Pathway β Complete Route
(Duodenum β Jejunum β Ileum) β LARGE INTESTINE
(Cecum β Colon β Rectum) β ANUS
| Organ | Secretion | Works On | Medium |
|---|---|---|---|
| Mouth | Salivary Amylase | Starch β Simple sugars | Neutral |
| Stomach | HCl + Pepsin + Mucus | Proteins β Peptides | Acidic (pH 1.6) |
| Liver | Bile (not enzyme) | Fat emulsification | Alkaline |
| Pancreas | Amylase, Lipase, Trypsin | Carbs, Fats, Proteins | Basic |
| Small Intestine | Intestinal enzymes | Final digestion + Absorption | Basic |
| Large Intestine | β | Water + Electrolyte absorption | β |
10. Respiration in Plants
π± By Roots
- Air soil particles ke beech spaces mein hoti hai (soil interspaces).
- Root hairs + epiblema cells (outermost layer of young roots) soil air ke direct contact mein.
- Oβ diffuse hoti hai root hairs β inner tissues β aerobic respiration β glucose break down β energy.
π By Leaves
- Leaves + young stems β thin structure + pores β quick gas exchange.
- Mature stems β impermeable epidermis β water loss prevent.
- Epidermis mein stomata (tiny openings) hote hain.
- Har stoma ke 2 guard cells hote hain β opening/closing control.
- Gas exchange + transpiration regulate karte hain.
Plants mein raat ko water loss β hydathodes (leaf edges pe present) ke through β water droplets ki form mein.
11. Human Respiratory System
12. Nose β Pharynx β Larynx β Trachea β Bronchi β Bronchioles β Alveoli
π Nose & Nasal Cavity
- Nose ke andar hair β dust + impurities trap karte hain.
- Mucus lining β air moisten karta hai, dust + bacteria trap karta hai, respiratory tract protect karta hai.
π£οΈ Pharynx
- Air aur food dono ke liye common passage.
- Nasal cavity ko larynx se connect karta hai.
- Air ko trachea ki taraf direct karta hai.
π€ Larynx (Voice Box)
- Vocal cords contain karta hai β air pass hone par sound produce hoti hai.
- Trachea ke top pe located hai.
π¬οΈ Trachea (Windpipe)
- Long tube β larynx se bronchi tak air carry karta hai.
- C-shaped cartilage rings β trachea ko collapse hone se rokΰ€€ΰ₯ hain, airway open rakhte hain.
πΏ Bronchi
- Trachea 2 bronchi mein divide hoti hai β ek har lung ke liye.
- Har bronchus lung mein enter karta hai, air deeper carry karta hai.
- Mucus + cilia β dust aur microbes trap karte hain.
π± Bronchioles
- Lungs ke andar har bronchus aur chhoti tubes mein branch karta hai = bronchioles.
- Narrower + more numerous β lungs mein air spread karte hain.
- Directly alveoli (air sacs) mein lead karte hain.
π«§ Alveoli
- Tiny balloon-like structures β bronchioles ke ends pe.
- Lungs mein millions of alveoli β capillaries (tiny blood vessels) se surrounded.
- Function: Oβ air se blood mein diffuse hoti hai β COβ blood se alveoli mein β exhale.
- Thin walls + large surface area β gas exchange bahut efficient.
13. Inhale vs Exhale
| Process | Rib Cage Movement | Diaphragm Movement | Lungs | Oβ (%) | COβ (%) |
|---|---|---|---|---|---|
| Inhale | Goes UP β | Goes DOWN β | Expands | 21% | 0.04% |
| Exhale | Goes DOWN β | Goes UP β | Contracts | 16.40% | 4.4% |
14. Epiglottis
Epiglottis kya karta hai?
Hamara airway protect karta hai β swallowing ke time food aur liquid ko lungs mein enter hone se rokta hai.
15. Aerobic vs Anaerobic Respiration
| Basis | Aerobic Respiration | Anaerobic Respiration |
|---|---|---|
| Oxygen | Oβ required | Oβ NOT required |
| Site | Mitochondria + Cytoplasm | Cytoplasm only |
| End Products | COβ + HβO + Energy | COβ + CβHβ OH (ethanol) + Energy |
| Energy Released | Large amount | Small amount |
| ATP Produced | 38 ATP | Only 2 ATP |
| Example | Humans, most animals | Yeast (dough), Muscle cells (lack of Oβ) |
Yeast anaerobic respiration karta hai β COβ release β dough soft aur fluffy banta hai (baked goods mein use).
Muscles mein Oβ ki kami β Anaerobic respiration β Lactic acid accumulate hota hai β Cramps.
Glucose (CβHββOβ) β Pyruvate (3C) + 2 ATP
In Yeast (no Oβ): Pyruvate β Ethanol + COβ + Energy
In Muscles (no Oβ): Pyruvate β Lactic Acid + Energy
In Mitochondria (Oβ present): Pyruvate β COβ + HβO + Energy (Aerobic)
16. Cellular Respiration
Cellular Respiration kya hai?
Process jisme cells glucose (sugar) break down karte hain β Oβ ki presence mein β energy ATP (Adenosine Triphosphate) ke form mein release karte hain.
Formula: CβHββOβ + 6Oβ β 6COβ + 6HβO + Energy (ATP & heat)
17. Steps in Cellular Respiration
Glycolysis β Cytoplasm mein
Glucose (6C) β 2 molecules of Pyruvate (3C each). Small amount of ATP + NADH produce hote hain.
Krebs Cycle (Citric Acid Cycle) β Mitochondria mein
Pyruvate further break down hota hai. COβ release hoti hai. Energy carriers NADH + FADHβ produce hote hain.
Electron Transport Chain (ETC) β Inner Mitochondrial Membrane mein
NADH + FADHβ electrons donate karte hain. Oβ = final electron acceptor. Up to 34 ATP produce hota hai. Total ~38 ATP per glucose aerobic respiration mein.
| Step | Location | Input | Output | ATP |
|---|---|---|---|---|
| Glycolysis | Cytoplasm | Glucose (6C) | 2 Pyruvate (3C) | 2 ATP |
| Krebs Cycle | Mitochondria | Pyruvate | COβ + NADH + FADHβ | 2 ATP |
| ETC | Inner mitochondrial membrane | NADH + FADHβ | HβO | ~34 ATP |
| Total | β | β | β | ~38 ATP |