6.1 Digestion and Absorption

From MaritNy on Quizlet

Circular muscle

The inner layer of smooth (involuntary) muscle surrounding the small intestine. The muscle fibers form a circle around the the lumen.

Buccal cavity (mouth)

Organ with tongue and teeth where food is chewed and mixed with salivary amylase.

Esophagus (oesophagus)

Thin tube that carries food from the mouth to the stomach

Stomach

Large muscular sac for mechanical and chemical digestion (using protease enzyme)

Small intestine

Narrow, winding, tubular organ, where digestion of food and absorption of nutrients occurs

Large intestine (Colon)

Large tubular organ that removes water from the digestive tract

Pancreas

Gland, under the stomach which produces lipase, protease and amylase enzymes for digestion. (And insulin / glycogen)

Gall bladder

An oval sack found next to the liver, that stores bile

Anus

Muscular opening at the end of the large intestine

Salivary gland

Gland which produces and secretes salivary amylase

Absorption

The movement of soluble products from digestion into the blood or lymphatic system by diffusion, osmosis, or active transport.

Amylase

An enzyme that converts (amylose in) starch and glycogen into simple sugars (maltose).

Cellulose (fiber)

A polysaccharide which is the main component of plant cell walls

Dialysis

The diffusion of small solutes through a selectively permeable membrane. This process is used to remove excess waste and water from the blood.

Endopeptidase

A group of enzymes that catalyse the breakdown (hydrolysis) of peptide bonds within a polypeptide chain or protein molecule.

Epithelium

A thin layer of cells covering external and internal surfaces of the body, e.g. the lining of the intestines.

Glycogen

A polysaccharide, used for carbohydrate storage in animals (in liver and muscle tissue).

Lipase

An enzyme that catalyses the breakdown of lipids (e.g. triglycerides and phospholipids) into fatty acids and glycerol.

Liver

A large glandular organ above the stomach. It produces bile, stores glycogen and has various other metabolic processes.

Longitudinal muscles

The outer layer of smooth muscle, which runs along the length of the intestines.

Lumen

The inner space of any tube in the body, e.g. intestines, blood vessels.

Mucosa

A layer of mucus-secreting tissue lining the digestive tract.

Villi

Minute finger-shaped processes of the mucous membrane of the small intestine that absorb \n nutrients.

Egestion

The process of expelling undigested food, dead cells and bacteria from the intestines as faeces.

Assimilation

The products of digestion are absorbed by cells in the body (e.g. liver, muscle) an incorporated into the cell structure or stored.

Ingestion

Food is taken into the mouth for processing in the intestines

Digestion

The mechanical or chemical breakdown of large food molecules (e.g. starch, nucleic acids, proteins, lipids) into smaller monomer units.

Sub-mucosa

A layer found under the mucosa, containing blood vessels and lymphatic tissue.

Peristalsis

Involuntary waves of muscle contraction that keep food moving along in one direction through the digestive system.

Enteric nervous system

The nervous system of the digestive tract