Summarize the effects of the cephalic phase, gastric phase, and intestinal phase on acid secretion by the stomach
What will be an ideal response?
The initial cephalic phase is mediated by the sight, smell, taste, or even thought of food. This phase, which is directed by the CNS, prepares the stomach to receive food by increasing the release of hydrogen ions into it. During the second phase, the gastric phase, two stimuli trigger acid secretion: 1 ) distention of the stomach wall and, 2 ) the presence of partially digested proteins in gastric juice both stimulate acid secretion. The final phase, the intestinal phase, is triggered by the presence of partially digested proteins in the fluid entering the duodenum which initially stimulates acid secretion. However, as chyme continues to enter the duodenum, a declining pH and the presence of lipids triggers the enterogastric reflex which decreases acid secretion.
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Put the following structures in order from superficial to deep. 1. muscle fiber 2. perimysium 3. myofibril 4. fascicle 5. endomysium 6. epimysium
What will be an ideal response?
When a muscle is isometrically contracted, its length ________ change.
A. does not B. does
The study of the structure and shape of the body and its parts and their relationships to one another is called ________
A) anatomy B) physiology C) homeostasis D) negative feedback E) irritability
Which type of tissue would you expect to find in an area where the rapid diffusion of substances is required?
A. Stratified columnar epithelial tissue B. Pseudostratified columnar epithelial tissue C. Simple squamous epithelium D. Stratified squamous epithelial tissue E. Stratified cuboidal epithelium