Practical 3 (Digestive Written Questions)

Alimentary canal (Gastrointestinal Tract) (Functions)

Digest and absorbed food

Alimentary canal (Consist of)

Mouth, pharynx, esophagus, stomach, small intestine, large intestine, and anus

Accessory digestive organs (Consist of)

Teeth, tongue, gallbladder, salivary glands, liver, and pancrease

Mouth (F)

Physical breakdown of food (driven by the muscles of mastication)

What is the beginning of the digestive track?

Mouth

Mouth (Tissue)

Non/lightly keratinized stratified squamous epithelium

Non/lightly keratinized stratified squamous epithelium (Function)

Protects underlying tissues from abrasion

Esophagus (F)

Propels food and liquid from the pharynx through the diaphragm and into the stomach (peristalsis)

Is the Esophagus a closed or open tube?

Closed tube

Where does the Esophagus begin?

6th cervical vertebrae

What is the top layer of the Esophagus composed of?

Skeletal Muscle

What is the middle layer of the Esophagus composed of?

Skeletal muscle & Smooth muscle

What is the lower layer of the Esophagus composed of?

Smooth muscle

What is the inner layer of the Esophagus composed of? (Tissue)

Stratified squamous epithelium

What is the outer layer of the Esophagus called?

Adventitia

What tissue is the Adventita compsoed of? (Esophagus)

Connective tissue

What are the 4 layers of Esophagus composed of?

Mucosa. Submucosa, Muscularis externa, and Adventita

Stomach (Function)

Mechanically churns food into liquid chyme and uses pepsin and hydrochloric acid to chemically digest proteins

Stomach (Mucosa Tissue)

Simple columnar epithelium

Stomach (Muscularis Externa Tissue)

Smooth muscle

Stomach (Muscularis Externa Layers)

Inner oblique layer, middle circular layer and outer longitudinal layer

Stomach (Serosa Tissue)

Connective Tissue and Simple Squamous Epithelial

Stomach (Mucosa) has depressions called?

Gastric pits

Which side of the body is the Stomach on?

Left side

Where does the Stomach receives it’s contents from?

Esophagus

The inner surface of the Stomach haas a series of folds called?

Rugae

Rugae (F)

Allows expansion of the stomach

Small Intestine (F)

Primary site for chemical digestion of food and absorption of nutrients

Small Intestine (Inner lining tissue & cells)

Simple columnar epithelium with goblet cells

Small Intestine (3 parts)

Duodenum - Ileum - Jejunum

Duodenum (Histology)

Duodenal (Brunner’s) glands

Ileum (Histology)

Peyer’s patches

Jejunum (Histology)

Intestinal crypts

Pancrease (Functions)

Secretes pancreatic juices and neutralizes stomach acids

Absorptive Cells (Functions)

Absorb food into the blood and produce enzymes

What distinguishes the Small Intestine from the Stomach and Large intestine?

Villi

Villi (Small Intestine) (F)

Increase surface area of the mucosa

Lacteals (Small Intestine) (F)

Transport lipids as chylomicrons via lymphatic vessels to bloodstream

Large Intestine (F)

Absorbs water, some vitamins, solutes, and form feces

Large Intestine (6 parts)

Cecum - Ascending colon - Transverse colon - Descending colon - Sigmoid colon - Rectum

Large Intestine (Mucosa tissue)

Simple columnar epithelium

Large Intestine (Histology)

Large number of goblet cells and wall is concentrated with lymphocytes

Large Intestine & Stomach don’t have what Histology structure?

Villi

Anal Canal (Tissue)

Stratified squamous epithelium (resist abrasion during defecation)

Salivary Glands (F)

Secretes saliva in the mouth

Salivary Glands (Parotid)

Secretion is mainly serous (H2O and enzymes)

Salivary Glands (Submandibular)

Secretion is mixed with mucinous and serous

Salivary Glands (Sublingual)

Secretion is mainly mucinous (mucus and enzymes)

Appendix (F)

Houses lymphoid nodules that play a role in the immune system

Liver (Functions)

Produce bile and plasma proteins; detoxifies harmful material

Liver (Histology Structures)

Central vein, hepatic lobules, hepatocytes, and portal triad

Gallbladder (F)

Stores bile

True/False: Does the Pancrease have Endocrine and Exocrine functions?

True

Goblet Cell (Functions)

Secretes mucus to lubricate the digestive tract and protect the epithelial lining from acid and friction

Rectum (F)

Temporally stores formed feces until they can be eliminated from the body (defecation)

Spleen (Functions)

Filters old red blood cells from blood and initiate immune response

Epiglottis (F)

Protects the opening of the larynx during swallowing

Trachea (F)

Conducts air from larynx to the lungs

Propulsion (Swallowing)

Oropharynx

Propulsion (Peristalsis)

Esophagus, stomach, small intestine and large intestine

Chemical Digestion

Stomach, small intestine and large intestine

Absorption (Nutrient & H2O to blood vessels and lymphatic vessels)

Small Intestine

Absorption (H2O to blood vessels)

Large Intestine

Mechanical Digestion (Chewing)

Mouth

Mechanical Digestion (Churning)

Stomach

Mechanical Digestion (Segmentation)

Small Intestine

Absorptive Cells (Simple Digestive Function)

Absorption

Appendix (Simple Function)

Immune Role

Epiglottis (Simple Digestive Function)

Propulsion and Swallowing

Esophagus (Simple Digestive Function)

Propulsion (peristalsis moves bolus)

Gallbladder (Simple Digestive Function)

Secretion

Goblet Cells (Simple Digestive Function)

Secretion (mucus)

Lacteal (Simple Digestive Function)

Absorption (lipids and fats)

Large Intestine (Simple Digestive Function)

Propulsion, chemical digestion, absorption

Liver (Simple Digestive Function)

Secretion (produces bile)

Mouth (Simple Digestive Function)

Ingestion and mechanical digestion

Pancreas (Simple Digestive Function)

Chemical Digestion (enzymes)

Rectum (Simple Digestive Function)

Defecation (stores feces)

Rugae (Simple Digestive Function)

Mechanical Digestion

Salivary Glands (Simple Digestive Function)

Secretion

Small Intestine (Simple Digestive Function)

Propulsion, chemical digestion, mechanical digestion and absorption (primary site)

Spleen (Simple Function)

Blood filtration

Stomach

Propulsion, chemical digestion, mechanical digestion (churning)

Trachea (Simple Function)

Air passage

Villus (Simple Digestive Function)

Absorption (nutrients)

Pathway of Food (Alimentary Canal)

Mouth - Pharynx - Esophagus - Stomach - Small Intestine - Large Intestine - Rectum - Anus

What is this test?

Iodine Test

What is this test?

Benedict’s Test

What is this test?

Litmus Test

Iodine test (What chemical/reagent is used?)

Iodine and potato starch solution

Iodine test (Procedure)

Add starch solution to test tube - add few drops of Iodine - observe color change

Iodine Test (+) Result

Blue/Black = starch present

Iodine Test (-) Result

Yellow/Brown = no starch

Iodine test (What are you testing for?)

Presence of starch

Benedicts Test (What chemical/reagent is used?)

Benedicts reagent and maltose (sugar) solution

Benedict’s test (Procedure)

Add sugar solution to test tube - add Benedict’s reagent = heat in boiling water bath - observe color change

Benedict’s test (Results - Blue color)

No reducing sugar present

Benedict’s test (Results - Green color)

Trace amount of reducing sugars

Benedict’s test (Results - Yellow color)

Low/moderate amount of reducing sugars

Benedict’s test (Results - Orange/Red color)

Large amounts of reducing sugar