[Zoo301l] Lab Reviewer

1. Oral Cavity and Pharynx a. Salivary Glands o Parotid Gland – located ventrad and craniad of the base of the pinna of the ear, just under the skin  It’s duct passes across the external surface of the masseter muscle and penetrates the upper lip.  The opening of the duct may be sought for on the inside of the cheek opposite the last cusp of the third upper premolar, which is situated on a slight ridge. o Submaxillary Gland – roundish mass at the angle of the jaw near the posterior margin of the masseter  The duct is springs from the internal surface. o Sublingual Gland – Elongated gland that surrounds the beginning of the submaxillary duct  The duct is found to pass internal to the digastric muscle. o Molar Gland – situated between the skin and the external surface of the mandible, just in front of the masseter muscle (cat only) o Infraorbital Gland – lies on the floor of the orbit b. Oral Cavity o Vestibule of the mouth – part of the oral cavity lying between the teeth and lips o Hard Palate – anterior portion of the roof of the oral cavity and is supported by premaxillary, maxillary, and palatine bones  Openings of the Nasopalatine Ducts – connects the mouth and nasal cavities by the way of the incisive foramina of the maxillary bones o Soft Palate – posterior portion of the roof of the oral cavity which lacks bone support o Tongue – fleshy muscular organ formed by the fusion of four components and has a more complicated intrinsic and extrinsic musculature than the tongue of lower vertebrates  Filiform Papillae – anterior part of the tongue which are hard and spinelike  Fungiform Papillae – remainder of the tongue  Vallate Papillae – among the fungiform papillae arranged in a V-shaped row, each consisting of a round elevation set into a pit (4-6 vallate papillaes)  Frenulum – vertical fold at the anterior margin of the attachment of the tongue to the floor of the oral cavity c. Pharynx o Pharynx – portion of the cavity lying posterior and dorsal to the soft palate o Isthmus of the Fauces – opening formed by the free border of the palate o Tonsillar Fossa – a pit located anterior to the free border of the palate which contains a small mass of lymphoid tissue, the palatine tonsil  Glossopalatine Arch – anterior low fold that bounds the front of the tonsillar fossa  Pharyngopalatine Arch – posterior low fold that bounds the front of the tonsillar fossa o Nasopharynx – part of the pharynx dorsal to the soft palate  Posterior Nares or Choanae – (2) internal ends of the nasal passages located at the anterior end of the nasopharynx  Auditory or Eustachian Tubes – cannals which connect the pharynx with the cavity of the middle ear o Esophagus – posterior narrow of the pharynx; opening which proceeds posteriorly dorsal to the larynx o Epiglottis – projecting process that guards the esophagus 2. Hyoid Apparatus, Larynx, Trachea, and Esophagus  Hyoid – narrow bone located at the external surface of the base of a bone of the lower jaw that is derived from the second and third gill arches  Anterior Horn – long and slender and consists of a chain of four bony pieces, the last of which articulates with the tympanic bulla  Posterior Horn – short and is united to the larynx  Larynx – chamber of cartilaginous walls in the median ventral line posterior to the body of the hyoid and constitutes the projection in the throat popularly known as Adam’s apple; (aka “voice box”)  Glottis – large opening at the top of the larynx from whose ventral margin the epiglottis projects  Thyroid Cartilage – large shield-shaped cartilage that supports the ventral wall of the larynx  Cricoid Cartilage – forms a ring around the larynx which is posterior to the thyroid cartilage  Arytenoids – pair of projecting cartilages that supports the opening of the esophagus  True Vocal Cords – pair of folds that extends from the arytenoid cartilages to the thyroid cartilage  False Vocal Cords – situated lateral to the true vocal cords and extends from the tips of the arytenoid cartilages to the base of the epiglottis  Thyroid Gland – flattened, elongated body that lies against the trachea and internal to the muscles on each side of the trachea  Isthmus – connects the two lobes of the thyroid gland which crosses the ventral side of the trachea 3. Pleural and Pericardial Cavities

A.

Thoracic Region a. Two Pleural Cavities  Mediastinal Septum – partition from the heart to the ventral median line and consists of two medial walls of the right and left pleural sacs in contact with each other  Mediastinum – space between the two walls of the mediastinal septum  Diaphragm – muscular dome-shaped partition that forms the posterior wall of the pleural sac  Pleura – smooth moist membrane that lines the pleural sac  Parietal Pleura – lines the inside of the pleural cavity and covers the anterior face of the diaphragm; together with the medial wall of the other pleural sac forms the mediastinal septum  Visceral Pleura – part of pleura which passes over the surface of the lung which it is indistinguishably fused o Left Lung - divided into three lobes and is composed of innumerable minute air cells called alveoli  Anterior Lobe – smaller  Middle Lobe – larger  Posterior Lobe - large o Right Lung – somewhat larger than the left lung  Anterior Lobe  Middle Lobe  Posterior Lobe  Medial Lobule - projects into a pocket formed by a special, dorsally directed fold (caval fold that supports the postcaval vein which ascends from the liver to the heart) of the mediastinal septum  Lateral Lobule  Pericardial Cavity – narrow space between pericardial sac and heart  Heart o Visceral Pericardium – thin membrane that invests the heart; continuous with the pericardial sac at the anterior end, where the blood vessels enter and leave the heart o Parietal Pericardium – separated from the heart by the pericardial cavity  Thymus – mass of gland tissue found in the medial line ventral to the anterior part of the heart and extending forward  Dorsal Aorta – a very large vessel injected with a colored solution which arches away from the heart to the left and descends toward the diaphragm B. Abdominal Region 4. Peritoneal Cavity o Urinary Bladder – pear-shaped organ generally distended with fluid located at the posterior end of the peritoneal cavity; sac occupying the posterior end of the peritoneal cavity, immediately internal to the body wall and ventral o the large intestine  Median Ligament – extends to the median ventral line; (also known as median umbilical fold of human anatomy)  Lateral Ligament – slightly developed ligament on each side of the bladder o Peritoneum – lines the peritoneal cavity  Parietal Peritoneum – portion of the membrane on the inside of body wall  Visceral Peritoneum – covers the surface of the viscera o Stomach and Spleen – attached to the left border of the liver lobes  Cardia – area of junction of the stomach and esophagus  Cardiac End of the Stomach – region of the stomach adjacent to the junction  Lesser Curvature – concave anterior surface of the stomach from the cardia to the pylorus  Greater Curvature – larger, convex posterior surface  Fundus – saclike bulge of the stomach to the left of the cardia; the remainder is called the body  Rugae – marked ridges in the wall of the stomach  Pyloric Valve – thickened ridge at the pylorus o Spleen – large organ that lies in the left side of the stomach o Messenteries and Ligaments  Greater Omentum – thin membrane impregnated with streaks of fat that ventrally covers the intestine  Mesogaster – extends from the dorsal wall to the stomach  Gastrosplenic Ligament – portion of the great omentum between the spleen and the stomach  Gastrocolic Ligament – secondary fusion formed between the mesogaster and the mesentery of the intestine  Falciform Ligament – a thin sheet with a concave posterior border which extends from between the two median lobes of the liver to the median ventral line  Coronary Ligament – a stout ligament which attaches the liver to the central tendon of the diaphragm  Mesoduodenum – part of the dorsal mesentery that supports the duodenum  Duodenorenal Ligament – mesentery fold attached to the right kidney  Mesocolon – mesentery of the colon

o

o

Pancreas – a pinkish gland which extends to the left into the dorsal of the greater omentum, dorsal to the greater curvature of the stomach; it is located in the mesoduodenum  Pancreatic Duct – joins the common bile duct at the point where the latter enters the duodenum  Ampulla of Vater – slightly swollen chamber where bile and pancreatic ducts unite  Accessory Pancreatic Duct – enters the duodenum about three-quarters of an inch cauded of the principal duct Small Intestine  Duodenum – first portion of the small intestine

Jejunum – portion beyond the duodenum of the small intestine Ileum – remainder of the small intestine Ileocolic Valve – an elevation projecting into the ileum Villi – finger-like projections inside the small intestine Caecum – junction of a small and large intestine Large Intestine – also called as the colon  Ascending Colon  Transverse Colon  Descending Colon Rectum – terminal portion of the descending colon    

o o

o

o

Peyer’s Patches – occur as oval light-colored spots along the colon