ANATOMI FISIOLOGI

SISTEM PENCERNAAN

MANUSIA

dr. Andika Eka Herlina

PENGERTIAN

Sistem pencernaan adalah suatu sistem organ yang bekerja menerima makanan dari luar dan mempersiapkannya untuk diserap oleh tubuh melalui rangkaian proses tertentu baik secara mekanis maupun enzimatik.

FUNGSI SISTEM PENCERNAAN

The function of the digestive system is to change these complex organic nutrient molecules into simple organic and inorganic molecules that can then be absorbed into the blood or lymph to be transported to cells (Scanlon, 2007)

BAGIAN SISTEM PENCERNAAN

2 divisions of the digestive system are : The alimentary tube extends from the

mouth to the anus. It consists of the oral cavity, pharynx (oropharynx), esophagus, stomach, small intestine, and large intestine

The accessory organs of digestion are the teeth, tongue, salivary glands, liver, gallbladder, and pancreas. Digestion does not take place within these organs, but each contributes something to the digestive process

(Scanlon, 2007)

JENIS PROSES PENCERNAAN

Mechanical digestion is the physical breaking up of food into smaller pieces. Example: Chewing

The work of the digestive enzymes is the chemical digestion of broken-up food particles, in which complex chemical molecules are changed into much simpler chemicals that the body can utilize. Such enzymes are specific with respect to the fat, protein, or carbohydrate. Example: protein-digesting enzymes work only on proteins, not on carbohydrates or fats.

(Scanlon, 2007)

MOLEKUL ORGANIK DALAM MOLEKUL ORGANIK DALAM MAKANANMAKANAN

3 types of complex organic molecules found in food are : – Carbohydrates (amilum & disaccharides)

are digested to maltose & monosaccharides such as glucose, fructose, and galactose

– Proteins amino acids– Fats fatty acids and glycerol

Also part of food, and released during digestion, are vitamins, minerals, and water (Scanlon,2007)

SISTEM PENCERNAAN

Oral cavity (teeth, tongue and the openings of the ducts of the salivary glands)

Pharynx Esophagus Stomach / Gaster (Cells: mucous, chief,

parietal, G) Small intestine (Cells: goblet, microvilli,

enteroendocrine; Liver, Gallbladder, Pancreas)

Large intestine Anus

ORAL CAVITY

Batas Rongga Mulut :– Superior : palatum durum (hard palates)

& palatum mole (soft palates)– Lateral : mukosa pipi– Inferior : dasar mulut

Di dalam rongga mulut terdapat :– Gigi geligi– Lidah– Muara kelenjar liur

ORAL CAVITY

Teeth – Fungsi : mengunyah (proses mekanik dimana

makanan diubah menjadi potongan-potongan yang lebih kecil, sambil dicampur dengan air liur)

– Jenis gigi : sulung & permanen– Sulung 20 gigi (incisivus, caninus, molar)– Permanen 32 gigi (incisivus, caninus,

premolar, molar) Tongue

– Fungsi Lidah : membantu menggerakkan makanan saat dikunyah / ditelan, pengecapan (indera perasa), bicara

Salivary glands– Air liur / saliva = cairan pencernaan

dalam rongga mulut– Muara dari : kelenjar parotis,

submandibula, sublingual– Memicu sekresi saliva : makanan, benda

asing, bau makanan parasimpatis– Mengurangi sekresi : stress simpatis– Enzim Amylase : Amilum Maltose

Pharynx reflex– Oropharynx & Laryngopharynx– Food passageways connecting oral

cavity - esophagus, no digestion

Esophagus– Peristaltik, no digestion.– Lower esophageal sphincter

Relax bolus masuk ke lambung Kontraksi mencegah cairan lambung

masuk ke esofagus

Stomach / GasterStomach / Gaster

Mucous cell mucus

Parietal cell HCl & faktor intrinsik

Chief cell Pepsinogen

G cell hormon GastrinHCl : Pepsinogen pepsin

Pepsin : Polypeptide peptide

Pencernaan Enzimatikmolekul organik kompleks

Lokasi pencernaan

Perubahan molekul yang terjadi

Karbohidrat 1. Mulut

2. Duodenum

3. Jejunum - Ileum

1. Amilum maltosa (amylase saliva)2. Amilum maltosa (amylase pancreas)3. Maltosa glucosa + glucosa (maltase)Laktosa glucosa + galactosa (lactase)Sukrosa glucosa + fruktosa (sucrase)

Protein 1. Lambung2. Duodenum3. Jejunum - Ileum

1. Protein polypeptide (pepsin)2. Polypeptide peptide (trypsin)3. Peptide asam amino (peptidase)

Lemak 1. Duodenum, jejunum, ileum

1. Lipid lipid teremulsi (garam empedu)Lipid teremulsi asam lemak + glycerol (lipase)