BIO 132 – Anatomy and
Physiology II
Study Outline
3.1. Role of the Digestive System in Homeostasis:
a. Constancy of the internal environment involves the supply of _______________ to our cells in order to make ATP.
b. In the form that it is consumed, much of the food that we eat cannot be used as fuel for ATP production, but instead must be broken down into ____________________. The process of breaking down food into simple nutrients that can be absorbed is called _______________.
c. The digestive system also serves as an excretion pathway in which the body rids itself of __________________.
d. The lumen of the digestive system is open to the ________________, meaning that structural specializations are needed to prevent invasion by foreign material. Further, the digestive system also contains many cells of the ______________ system that are responsible for killing any invading organisms.
3.2. Organs of the Digestive System:
a. Anatomically, the digestive system can be subdivided into the ______________________ and ___________________________.
b. The GI tract extends from the _________________ to the _______________, and consists of the following organs: _______________, ________________, __________________, _________________, _________________, and __________________.
c. The accessory GI glands are all examples of ________________ glands whose ducts drain to the ________________. The accessory GI glands include the _________________, ________________, _________________, __________________ and gallbladder, and __________________.
d. In addition there are two examples of accessory digestive organs located in the oral cavity. These are the _________________ and __________________.
3.3. Digestive System Functions:
a. The seven basic functions of the digestive system are ___________________, ___________________, _____________________, ____________________, __________________, _________________, and ______________________.
b. The process of digestion involves two distinct phases called _______________ and _________________. ________________ refers to the physical breakdown and solubilizing of food. It begins in the _________________. By contrast, chemical digestion refers primarily to the action of ________________which catalyze the conversion of food into simpler molecules.
c. The process by which nutrient molecules are taken up from the GI tract lumen is called _______________. Most nutrients pass to _______________ but large fats pass first to __________________.
d. ___________________ is a coordinated series of actions produced by the tongue and other skeletal muscles by which a food bolus is transferred from the oral cavity into the pharynx.
e. The ability for food to pass down the esophagus to the stomach while standing on our heads is due to the process of ___________________.
f. _________________ refers to the rhythmic local contractions within the intestines that aid in mixing and mechanical digestion.
g. Indigestible substances are eliminated from the body via the _______________ in the form of _________________.
h. An example of a waste substance that is excreted from the body by the digestive system is __________________.
3.4. The Peritoneum:
a. The portion of the peritoneum in contact with a peritoneal organ is called the _________________ peritoneum. This structure consists of a single layer of cells called __________________ cells.
b. An organ that comes to lie behind the peritoneum is referred to as being ______________________.
c. The structure through which blood vessels and nerves pass to and from peritoneal organs is called a ____________________.
d. An over-accumulation of peritoneal fluid results in a condition called ______________________.
e. Infection of the peritoneum gives rise to a condition known as ____________.
f. As the peritoneal layers become more complex, they give rise to a number of named anatomical structures. For example, the structure that represents the ventral mesentery of the liver is called the __________________. The structure that suspends the stomach from the liver is called the __________________. The double sheet that attaches to the greater curvature of the stomach and the transverse colon is called the ___________________. Finally the dorsal mesentery suspending the transverse colon is called the _________________.
3.5. The General Organization of the GI Tract:
a. Of the four basic histological layers, the one that lies closest to the lumen is called the ___________________, named because of the presence of glands which secrete __________________ onto the lumenal surface.
b. Within the GI tract, two epithelial types are found. These are __________________ and _____________________. Of these two types, ___________________ serves primarily a protective function whereas the simple columnar epithelium serves the functions of _________________ and _____________________.
c. Adjacent cells are connected by _________________ junctions, structures which limit the diffusion of materials back and forth across the epithelium.
d. Within the mucosa, the layer immediately subjacent to the epithelium is called the ___________________. Found in this layer are a series of cells of the immune system, collectively referred to as __________________.
e. Smooth muscle is found in two separate layers: the _________________ and the ___________________.
f. The nervous structure that controls mucosal secretion is called the ______________ plexus and is found in the ________________. By contrast the structure that controls the motility of the muscularis externa is called the ______________ plexus and is found between the _________________ and _______________ layers.
g. Smooth muscle sphincters in the GI tract are created by a thickening of the _________________ layer of the ____________________.
h. For a peritoneal organ, the outermost layer of the organ wall is called the ________________ whereas if the organ is retroperitoneal, the layer is referred to as the _________________.
3.6. Anatomy of the Oral Cavity:
a. In the general sense the oral cavity is a space bounded by the ________________, _______________, _______________, and the _________________. Actually the ________________ is the space located between the teeth and gums ® cheeks and lips, whereas the oral cavity proper is the space beween the teeth and gums ® _____________________.
b. The name of the skeletal muscle found in histological sections of the lip is the _____________________.
c. The ___________________ is a small fold of tissue that connects the lips to the gums.
d. The palate consists of two parts called the ________________ palate and the _________________ palate. The structure that dangles down from the back of the soft palate is called the __________________.
e. The two arches that descend from the palate are called the ________________ and _____________________ arches.
3.7. The Tongue:
a. The tongue functions not only to move food around, but also contains structures which provide us with the sensation of _____________________.
b. The ___________________ is a structure that attaches the tongue to the floor of the mouth. The condition in which this structure is not formed properly and gives rise to speech impediments is called ________________________.
c. The tongue has several types of specialized structures called ________________. Of these the _____________________ are pointed structures that help the tongue to develop friction with the food. The two types which are mushroom-shaped are the ____________________ and ______________________.
d. The ____________________ divides the tongue into anterior 2/3s and posterior 1/3. The _____________________ are found in the posterior 1/3 of the tongue.
3.8. Teeth:
a. Teeth are held into place into bone by structures called __________________ ligaments. The name of the bone which contains the upper teeth is the ___________________ whereas the bone which contains the lower teeth is called the ______________________.
b. Teeth are classified as ________________, _________________, _________________, and ___________________.
c. The portion of a tooth that extends above the gingiva is called the _______________ and is covered by a material called __________________.
d. The portion of a tooth that lies within the socket is called the __________________. In this region the outer surface of the tooth is covered by a material called ____________________.
e. Dentin is secreted by cells called ______________________.
f. A root canal involves a cleansing and filling of the _____________________.
g. The clinical name for a cavity is dental _______________________which results from a gradual ____________________ of the enamel and dentin through bacterial action. By contrast inflammation of the gums is called ______________________.
3.9. The Esophagus:
a. The esophagus is a muscular tube which conveys food and drink from the ___________________ to the ___________________. In so doing, the esophagus passes through a hole in the ___________________ called the esophageal ____________________.
b. At the junction of the esophagus and stomach there is a structure called the ____________________ sphincter, which represents a __________________ instead of an anatomical sphincter because of the lack of any structural specialization.
c. In the esophagus the epithelium is _____________________.
d. The components of the wall of the esophagus vary between different regions. For example, in the upper 1/3 of the esophagus, the muscle type in the muscularis externa is exclusively ______________________ whereas in the lower 1/3, there is only _____________________ muscle in this layer. Similarly, the ______________________ becomes an increasingly intact layer moving from upper to lower regions.
e. Heartburn is attributable to esophageal ___________________, which when persistent can give rise to a condition known as _______________________.
f. The outermost layer of the esophagus is called the _____________________.
3.10. The Stomach:
a. The stomach is a temporary storage organ in which food and drink are converted into a paste-like substance called ________________________.
b. The size of the stomach can vary considerably. When empty, the wall is thrown into a series of folds called ____________________.
c. The stomach has two curves called the __________________ and ________________ curvatures.
d. Anatomically, the stomach is subdivided into four regions called the _________________, ___________________, ____________________, and the ___________________. Of these the _________________ and the ______________________ are histologically indistinguishable.
e. Unlike other portions of the GI tract the muscularis externa of the stomach has a third layer of obliquely oriented smooth muscle located in the ________________ layer of the muscularis externa.
f. The mucosa is organized into a series of depressions called _________________which lead to _____________________which extend nearly as far as the _____________________.
g. The cell type that lines the surface and pits of all regions of the stomach is called the ____________________ cell. As their name suggests, their main secretory product is __________________which forms a protective layer along the epithelial surface.
h. Within the body and fundus of the stomach, the gastric glands contain additional cell types. For example, __________________ cells secrete stomach acid and ___________________. __________________ cells, on the other hand secrete ____________________ and small amounts of gastric lipase. Finally throughout the stomach mucosa are found cells called _____________________ cells which release hormones.
i. The pyloric and cardiac portions of the stomach can be distinguished by the relative lengths of their pits and glands. In the pyloric stomach the pit/gland ratio is ____________________ than that of the cardiac stomach.
j. Factors which predispose one to gastric ulcers are anything that causes ____________________ of stomach acid or __________________ of mucus. Because of its relation with the peritoneum, perforating ulcers can lead to _______________________.
k. _____________________ cells located near the base of the gastric glands secrete ________________ and cholecystokinin.
3.11. The Small Intestine:
a. The small intestine extends from the __________________ to the _________________.
b. The three portions of the small intestine are called the _________________, ___________________, and _____________________.
c. The duodenum receives the exocrine secretions from the ___________________ and the _____________________.
d. The mucosa throughout the small intestine is organized into projections called __________________ and glands which are also called ___________________. Superimposed on this arrangement, in many places projections of the submucosa pushing the mucosa ahead into the lumen are called _____________________.
e. Within the ____________________ are found many lymphatic vessels which receive absorbed fats. These are called _____________________.
f. Within the small intestine there are many examples of lymph nodules which are referred to as __________________ patches.
g. The epithelium throughout the small intestine consists of the tissue type ____________________. Within this epithelium the cell types are predominantly ________________ and _____________________. But at the base of the crypts are found two additional cell types: __________________which secrete lysozyme; and _________________ which secrete hormones.
h. There are a number of structural specializations for increasing surface area in the small intestine which include ________________, _________________, and ______________________.
i. Special mucous glands in the submucosa of the ___________________, called ____________________ are responsible for neutralizing stomach acid coming through the pyloric sphincter.
j. Goblet cell frequency ___________________ as a function of distance along the small intestine. Paneth cell frequency ____________________ as a function of distance along the small intestine.
k. Plicae circulares are tallest in the _______________________.
l. At the junction with the large intestine, there is a sphincter called the ________________________.