A&P 2452 Exam 2
Draw cardiac muscle and label the major components.
girl go look on google
What is are the primary functions of the paranasal sinuses in respiration?
lightening the weight of the head, humidifying, and heating inhaled air, increasing the resonance of speech, and serving as a crumple zone to protect vital structures in the event of facial trauma.
What are some homeostatic imbalances associated with the small and large intestines?
• Appendicitis- blockage of feces and traps infectious bacteria in its lumen • Clostridium difficile- inflammation to the colon that leads to bowel perforation and sepsis
Describe bile and its components.
• Bile is a yellow-green, alkaline solution containing bile salts, bile pigments, cholesterol, triglycerides, phospholipids and a variety of electrolytes
Describe the microscopic anatomy of the small intestine and how its structures facilitate absorption.
• Circular folds: these folds force chyme to spiral through the lumen, slowing it movement and allowing time for absorption • Villi: increase surface area for food absorption and adding digestive secretions • Microvilli: complete the digestion of carbs and proteins in the small intestine
Describe the gross anatomy of the large intestine and the haustra. What is the functional role of the haustra?
• Contains the teniae coli, which contracts length wise to produce the haustra • Haustra are saccules in the colon that give segmented appearance • function: contraction is activated by presence of chyme; moves food down the next haustra
What is the function of each major part of the small intestine?
• Duodenum: responsible for the continuous breaking-down process • Jejunum and Ileum: responsible for the absorption of nutrients into the bloodstream
What are gall stones and how do they contribute to homeostatic imbalance? (See Figure 23.9)
• Gall stones: are cholesterol crystalized • Gall stones can obstruct the flow of bile from the gallbladder
List each major organ of the digestive system and give the overall function.
• Mouth: saliva mixes with the food to begin to break it down into a form the body can absorb • Esophagus: a series of muscular contractions within the esophagus called peristalsis delivers food to stomach • Stomach: holds food while it is being broken down by enzymes • Small intestine: breaks down food using enzymes released by the pancreas and bile from the liver • Pancreas: secretes digestive enzymes into the duodenum that break down proteins, fats, and carbohydrates • Liver: Process the nutrients absorbed from the small intestine • Gallbladder: stores and concentrates bile from the liver, and releases it into the duodenum in the small intestine to help absorb and digest fats. • Colon (large intestine): processes waste so that emptying the bowels is easy and convenient • Rectum: receives stool from colon and holds it until evacuation happens • Anus: Where waste is released and exits
What are the major types of gland cells and their functions, in relation to the stomach? (See Figure 23.16)
• Mucous neck cells: produce a thin, soluble mucus • Parietal cells: secret hydrochloric acid and intrinsic factor • Chief cells: produce pepsinogen, the active form of the pepsin • Enteroendocrine cells: release a variety of chemical messengers directly into the interstitial fluid of the lamina propria
How are gastric secretions regulated in the stomach?
• Neural controls of gastric secretion happens by the vagus nerve and local enteric nerve; when the stomach is stimulated by the vagus nerve, secretory activity of virtually all of its glands increases • Hormonal control of gastric secretion happens the hormone gastrin; it stimulates the secretion of HCl by the stomach
Discuss the major digestive processes in the small intestine.
• Secreting enzymes for digestion • Regulating chyme entry
What is the role of the mesenteries in the digestive system? Describe those associated with the intestines, as shown in Figure 23.34.
• Suspends the small and large intestine from the posterior abdominal wall, anchoring them in place • The greater omentum, a dorsal mesentery, covering the abdominal viscera • The lesser omentum, a ventral mesentery attaching to the liver to the lesser curvature of the stomach
Describe the microscopic anatomy of the stomach (See Figure 23.16)
• The lining epithelium of the stomach mucosa is a simple columnar epithelium composed entirely of mucous cells. The smooth lining is dotted with deep gastric pits which lead into tubular gastric glands that produce the stomach secretion called gastric juice.
Explain the microscopic anatomy of the liver as shown in Figure 23.24.
• The liver is composed of sesame-seed-sized structural and functional units called liver lobules. Each liver lobule is a hexagonal structure consisting of plates of liver cells or hepatocytes. At each of the six corners of a lobule is a portal triad.
What is the main function of the liver?
• The main function is to process the nutrient rich blood delivered to it
What is the major function of the pancreas and what is its relationship with the liver?
• The major function of the pancreas it to produce enzymes that break down food • The bile duct, from the liver, and the main pancreatic duct, carrying pancreatic juice from the pancreas, unite in the walls of the duodenum
What is the role of the pancreas in digestion? What is it's relationship to the small intestine? (See Figure 23.27)
• The pancreas makes pancreatic juices called enzymes, which break down sugars, fats, and starches • The pancreatic enzymes empty out into the duodenum
What is deglutition? Explain this process. (See Figure 23.14)
• The process of swallowing • The buccal phase: the upper esophageal sphincter is contracted and the tongue presses against the hard palate, forcing the food bolus into the oropharynx • The pharyngeal-esophageal phase: the tongue blocks the mouth; the soft palate and its uvula rise, closing off the nasopharynx; the larynx rises so that the epiglottis blocks the trachea; the upper esophageal sphincter relaxes and food enters the esophagus; the constrictor muscles of the pharynx contract, forcing food into the esophagus inferiorly; the upper esophageal sphincter contracts after food enters • Peristalsis moves food through the esophagus to the stomach • The gastroesophageal sphincter surrounding the cardial orifice opens. After food enters the stomach, the sphincter closes, preventing regurgitation
Briefly describe how gastric motility and emptying are regulated.
• The relatively unchanging pressure in a filling stomach is due to the receptive relaxation and gastric accommodation • The rate of gastric emptying depends on the mixture of gastric juices and solid foods. It also depends on the contents of the duodenum
Discuss the structural modifications of the small intestine compared to other parts of the alimentary canal. Why does the SI need these modifications? See Figure 23.31
• The structural modifications are circular folds, villi, and microvilli that amplify its absorptive surface • The small intestine needs the modifications to increase the surface area for absorption
Describe an ulcer and its possible causes to your parents, explaining how it contributes to homeostatic imbalance (see Fig 23.7)
• Ulcer are open sores that develop on the inside lining of your stomach • 90% of ulcers are the work of a strain of acid-resistant, Helicobacter pylori bacteria, which burrow like a drill bit through the mucus and destroy the protective mucosal layer
Explain the structure and function of the villi and microvilli in the small intestines
• Villi: fingerlike projections, 1 mm high; each villi contains a dense capillary bed and a wide lymphatic capillary called a lacteal; absorbs nutrients • Microvilli: densely packed cytoplasmic extensions of the absorptive cells of the mucosa; complete the digestion of carbs and proteins in the small intestine
9. What is the respiratory zone, and what structures are part of this zone?
respiratory zone is found deep inside the lungs and is made up of the respiratory bronchioles, alveolar ducts, and alveoli. These thin-walled structures allow inhaled oxygen (O2) to diffuse into the lung capillaries in exchange for carbon dioxide (CO2).
Describe Dalton's law of partial pressure, and then explain why this law is important to understand respiration.
Dalton's law states that at any given time, the percentage of each of these gasses in the air we breathe makes its contribution to total atmospheric pressure, and this contribution will depend on how much of each gas is in the air we breathe.
Describe the transport and exchange of oxygen in the lungs as shown in Figure 22.25.
ALVEOLI are the very small air sacs where the exchange of oxygen and carbon dioxide takes place. CAPILLARIES are blood vessels in the walls of the alveoli. Blood passes through the capillaries, entering through your PULMONARY ARTERY and leaving via your PULMONARY VEIN.
What factors other than ANS and chemicals affect heart regulation?
Age, gender, exercise, and body temperature all influence heart rate.
What is meant by deciduous teeth and why do humans have this?
Deciduous teeth - commonly known as baby teeth, milk teeth, temporary teeth, and primary teeth - are the first set of teeth in the growth and development of humans and other diphyodont mammals. They're needed to preserve space for adult teeth while they are forming under our gums and inside our jaws. Our baby teeth serve as placeholders until our adult teeth are ready to come in.
What do the depolarization and repolarization have to do with how ECG's work?
Depolarization causes the P wave, the QRS complex, and repolarization causes the t wave.
Describe the action potential of contractile cardiac muscle cells as shown in Fig. 18.15. [be sure to describe all three steps]
Depolarization is due to an influx of Na+, which reverses the membrane potential. Next is the plateau phase, which is due to the Ca2+ influx which keeps the cell depolarized due to the K+ channels being closed. Lastly is repolarization, which is due to the Ca+ channels deactivating and the K+ channels opening which brings the membrane potential back to its resting voltage.
What is the relationship of the liver, gallbladder, and pancreas to the duodenum as described in Figure 23.28
Ducts from the pancreas, gallbladder, and liver empty into the duodenum
What is inspiration? What does this have to do with the diaphragm and the intercostal muscles?
During inspiration, the diaphragm and external intercostal muscles contract, causing the rib cage to expand and move outward, and expanding the thoracic cavity and lung volume. This creates a lower pressure within the lung than that of the atmosphere, causing air to be drawn into the lungs.
Describe the sequence of events in the thoracic cavity during inspiration and expiration as shown in Figure 22.16
During inspiration, the diaphragm contracts and the thoracic cavity increases in volume. This decreases the interalveolar pressure so that air flows into the lungs. Inspiration draws air into the lungs. The second phase is called expiration or exhaling. When the lungs exhale, the diaphragm relaxes, and the volume of the thoracic cavity decreases, while the pressure within it increases. As a result, the lungs contract and air is forced out.
Describe changes in intrapulmonary and intrapleural pressures during inspiration and expiration as shown in Fig. 22.17.
During inspiration, the volume of the thoracic cavity increases, causing intrapulmonary pressure to fall below atmospheric pressure. This is also known as a negative pressure. ... During expiration, the volume of the thoracic cavity decreases, causing the intrapulmonary pressure to rise above atmospheric pressure.
Explain th.is statement: gases exchange by diffusion between the blood, lungs and tissues.
External respiration is the exchange of gases with the external environment and occurs in the alveoli of the lungs. Internal respiration is the exchange of gases with the internal environment and occurs in the tissues. The actual exchange of gases occurs due to simple diffusion.
What are the layers of the heart wall? Describe each.
First there is the epicardium which is the outer layer of the heart, and anchors the heart to its place in the body and prevents overexpansion. Next is the myocardium which is the middle very muscular layer and initiates the contractions of the heart during systole. Lasty is the internal endocardium layer which lines the cavities and valves.
Discuss three differences in the physiology of skeletal and cardiac muscle. See Table 18.1.
Firstly, skeletal muscle does not contain gap junctions while cardiac does, secondly skeletal muscles have many t tubules while cardiac has few, and lastly skeletal muscle does not contain pacemaker cells while cardiac does.
Describe the tissue composition of the trachea wall as shown in Figure 22.8.
Four layers of tissues make up the walls of the trachea: The mucosa is the innermost layer and consists of ciliated pseudostratified columnar epithelium with many goblet cells. Deep to the mucosa is the submucosa layer, which is made of areolar connective tissue containing blood vessels and nervous tissue. Surrounding the submucosa is a layer of hyaline cartilage that forms the supportive rings of the trachea. The outermost layer of the trachea is the adventitia, a layer of areolar connective tissue that loosely anchors the trachea to the surrounding soft tissues.
What are the major functions of the large intestine, and describe how it helps do these tasks.
Function: to absorb most of the remaining water from indigestible food residues, stores residues temporarily, and then eliminate them from the body as feces
Describe the gross anatomy of the lungs.
The diaphragm is the flat, dome-shaped muscle located at the base of the lungs and thoracic cavity. The lungs are enclosed by the pleurae, which are attached to the mediastinum. The right lung is shorter and wider than the left lung, and the left lung occupies a smaller volume than the right.
What is the relationship of the digestive organs to the peritoneum? See Figure 23.4
The digestive organs within the abdominal cavity are held in place by the peritoneum, a broad serous membranous sac made up of squamous epithelial tissue surrounded by connective tissue.
Discuss the gastrointestinal tract activities as they are presented in Figure 23.2
The digestive system ingests and digests food, absorbs released nutrients, and excretes food components that are indigestible. The six activities involved in this process are ingestion, motility, mechanical digestion, chemical digestion, absorption, and defecation.
Describe the alimentary canal (or gastrointestinal tract) to grandma, explaining what it looks like, how large, and major parts.
The digestive system is made up of the alimentary canal (also called the digestive tract) and other organs, such as the liver and pancreas. The alimentary canal is the long tube of organs — including the esophagus, stomach, and intestines — that runs from the mouth to the anus.
Briefly describe the enterica nervous system of the GI tract. See Figure 23.7 [we didn't discuss this in detail during lecture, but I do want you to know this in general as it is important]
The enteric nervous system (ENS) is a quasi autonomous part of the nervous system and includes a number of neural circuits that control motor functions, local blood flow, mucosal transport and secretions, and modulates immune and endocrine functions.
What is the function of the esophagus?
The esophagus is a muscular tube that goes from your pharynx (throat) to your stomach. Food is pushed through your esophagus and into your stomach with a series of muscle contractions.
In terms of respiration, how do partial pressure gradients promote gas movement in the body (see Figure 22.20).
The greater the partial pressure of a gas, the more of that gas will dissolve in a liquid, as the gas moves toward equilibrium. Gas molecules move down a pressure gradient; in other words, gas moves from a region of high pressure to a region of low pressure
What bones are associated with the hard palate?
The hard palate is made up of four cranial bones: the paired maxillae and the paired palatine bones.
What is meant by "cardiac muscle cells are self-excitable"? Explain.
The heart contains pacemaker cells which can spontaneously depolarize which can then cause the depolarize the rest of the heart cells by way of gap junctions.
Explain to your kid sister in 7th grade what the intrinsic conduction system is and how it works.
The heart contains unstimulated contractile cells which have a stable resting point. The heart also contains pacemaker cells which have the ability to depolarize on their own which causes them to have an unstable resting point and spread action potential throughout the heart.
Explain why the heart has valves
The heart has valves to prevent backflow of blood.
Describe the human heart, in terms of some interesting trivia, its location and size.
The heart is located between the lungs, and more towards the medial body line instead of towards the side like most people think. It is typically the size of human fists put together, and is sort of cone shaped.
What are the effectors (cells that carry out the response)?
The heart, blood vessels, and kidneys act as effectors.
Explain how influx of Ca2+ from extracellular fluid triggers Ca2+ release from the sarcoplasmic reticulum.
The influx of Ca2+ causes Ca2+-sensitive channels in the SR to release bursts of Ca2+ that account for the other 80-90% of the Ca2+ needed for contraction.
What are the tunics, and discuss the structural differences between them?
The innermost tunica intima is made of mostly endothelial cells and is a barrier between blood and the vessel. The middle layer is the tunica media and is mostly smooth muscle which helps with vasoconstriction/vasodilation. The outermost layer is the tunica externa which is made of connective tissue and serves as protection and structure from the outside for the vessel.
What is the role of intercalated discs in the pacemaker?
The intercalated discs are meant to adhere specific cells to each other.
19. What are intercalated discs and what is their significance in the heart?
The intercalated discs connect cardiac cells, which allows the heart to contract in a wave like pattern.
Differentiate between the organs of alimentary canal vs. the accessory organs.
The organs of the alimentary canal are the mouth, pharynx, esophagus, stomach, small intestine, and large intestine. The accessory digestive structures include the teeth, tongue, salivary glands, liver, pancreas, and gallbladder.
What are vibrissae (of the nasal cavity) and what is their primary function for respiration? Where exactly in the nasal cavity are they located?
The other part of the nasal cavity, which is lined by the respiratory epithelium, is called nasal cavity proper. Inside the vestibule are small hairs called vibrissae, which filter dust and other matter that are breathed in.
Explain the oxygen-hemoglobin dissociation curve as shown in Figure 22.1.
The oxygen-hemoglobin dissociation curve, also called the oxyhemoglobin dissociation curve or oxygen dissociation curve (ODC), is a curve that plots the proportion of hemoglobin in its saturated (oxygen-laden) form on the vertical axis against the prevailing oxygen tension on the horizontal axis. This curve is an important tool for understanding how our blood carries and releases oxygen.
What is the papillary muscle and its function?
The papillary muscles attach to the atrioventricular valves by the chordae tendineae and contract to prevent the valves from opening the wrong way.
Describe the coverings of the heart, what types of tissues they are made of, and their function.
The pericardium is a double walled sac made up of the serous pericardium (inner) which is doubled layered, and the fibrous pericardium (outer) which prevents the heart from overfilling. Then there is the parietal layer which lines the internal surface of the fibrous pericardium and attaches the heart and the arteries exiting the heart. Lastly there is the epicardium which is the visceral layer of the serous pericardium and lines the surface of the heart.
Name the three parts of the pharynx. Which parts are used in respiration and how?
The pharynx is approximately 12.5 centimeters long and is divided into three parts. These parts include the nasopharynx, oropharynx, and laryngopharynx. The nasopharynx is the most superior, or uppermost, part of the pharynx that works with the nasal cavity during breathing. It provides a passageway for air moving from the nose. The oropharynx is behind the soft palate of the mouth and is below the nasopharynx. It serves as a passageway for food moving from the mouth to the esophagus and for air moving to and from the nasal cavity. The laryngopharynx lies inferior, or below, the oropharynx and serves as a passageway for food to the esophagus.
What are the pleurae and why are these structures important for respiration?
The pleurae refer to the serous membranes that line the lungs and thoracic cavity. The pleurae perform two major functions: They produce pleural fluid and create cavities that separate the major organs. Pleural fluid is secreted by mesothelial cells from both pleural layers and acts to lubricate their surfaces.
What is meant by the pleural cavity, and what structures are associate with it?
The pleural cavity is the potential space between the two pleurae (visceral and parietal) of the lungs. ... There are two layers; the outer pleura (parietal pleura) is attached to the chest wall and the inner pleura (visceral pleura) covers the lungs and adjoining structures, via blood vessels, bronchi and nerves.
Related to #29, what is meant by "autorhythmicity of the heart"?
The property of cardiac cells to depolarize spontaneously is autorhythmicity.
Describe the difference between the pulmonary circuit and systemic circuit of the heart.
The pulmonary system only circuits blood through the lungs and back to the heart in order to oxygenate it, while the systemic circuit circulates blood from the heart to the entire body and its tissues.
What is the role of the bacterial microbiota in the gut? See page 909
The role of the bacterial microbiota is fermentation and vitamin synthesis
What is the sarcomere? What does it have to do with muscle contraction?
The sarcomere is a unit of striated muscle tissue which is able to slide past each other in order to allow contraction.
Briefly described how nutrients are absorbed from food. (See section 23.10)
The small intestine absorbs most of the nutrients in your food, and your circulatory system passes them on to other parts of your body to store or use. Special cells help absorbed nutrients cross the intestinal lining into your bloodstream.
What causes heart sounds?
Heart sounds are caused by the opening and closing of heart valves.
Discuss how blood flows in relation to pressure.
Like all fluids, blood flows from areas of high pressure to low pressure. Due to the pressure in different blood vessels being different, arteries then capillaries then veins, blood flows in that direction which allows for gas exchange to occur through the capillary beds easily.
What are the main physical factors influencing pulmonary ventilation?
Lung compliance, alveolar surface tension, and airway resistance
What is the relationship between blood and lymphatic vessels?
Lymphatic vessels drain excess fluid and lymph from the tissues which blood supplies with nutrients, which prevents fluid build up in the tissues.
Why is the trachea lined with cilia?
Mucus helps to moisten and protect the airways. Mucus lines the ciliated cells of the trachea to trap inhaled foreign particles that the cilia then waft upward toward the larynx and then the pharynx where it can be either swallowed into the stomach or expelled as phlegm.
What are the major structures associated with the large intestine as shown in Figure 23.33?
Teniae coli, haustra, and epiploic appendages
Explain the intrinsic cardiac conduction system as shown in Fig. 18.13.
The SA node sends an impulse to the AV node then to the Av bundle, which branches out to the left and right bundle branches, and then throughout the heart through the subendocardial conducting network using purkinje fibers.
Explain how the pacemaker works to your 7th grade little sister.
The SA node, or the pacemaker, depolarized spontaneously and sends electrical impulses to the heart in order to get the heart to contract and pump blood. This is achieved by sending impulses down to the Av node, then to the bundle of HIS, then to the bundle branches, then to all of the skinny and long purkinje fibers
Describe the basic structure of the alimentary canal as shown in Figure 23.5
The alimentary canal forms a continuous tube that is open to the outside environment at both ends. The organs of the alimentary canal are the mouth, pharynx, esophagus, stomach, small intestine, and large intestine.
What are the three major cell types in the alveoli?
The alveolar wall consists of three major cell types: type I alveolar cells, type II alveolar cells, and alveolar macrophages.
19. Why are the air passageways in the lungs often referred to as the bronchial tree?
Bronchioles end in tiny air sacs called alveoli, where the exchange of oxygen and carbon dioxide actually takes place. Each person has hundreds of millions of alveoli in their lungs. This network of alveoli, bronchioles, and bronchi is known as the bronchial tree.
Discuss the function of each major component of the cardiac muscle.
Cardiac muscle cell, connected by intercalated discs, houses the mitochondrion, the sarcolemma covers the cell, the t tubules are far between, sarcoplasmic reticulum is simple and lacks large terminal cisterns, z discs are on sarcomeres which have a bands and I bands.
How do cardiac muscle fibers differ from skeletal muscle fibers? [see Table 18.1]
Cardiac muscle fibers are connected through intercalated discs and skeletal does not.
What is the relationship of the peritoneum to the mesenteries? See Figure 23.4
A mesentery is double layer of visceral peritoneum. It connects an intraperitoneal organ to (usually) the posterior abdominal wall. It provides a pathway for nerves, blood vessels and lymphatics to travel from the body wall to the viscera
What is meant by a partial pressure gradient?
A partial pressure gradient is the difference in the concentration of a gas in a mixture of gases, in which the gas is at a higher pressure in one location and a lower pressure in another location. A gas will diffuse from a higher pressure to a lower pressure down the gradient.
Discuss the hierarchical order of the bronchial tree, from largest to smallest.
trachea to main/R & L/primary bronchi (to lungs) to lobar = secondary bronchi (to lobes of lungs) to segmental = tertiary bronchi (to bronchopulmonary segment) to interlobular bronchi (to lobules) to a series of ever smaller lobular bronchioles (no more cartilage supports) which branch to terminal bronchioles which branch to form respiratory bronchioles (to alveolar sacs) to alveolar ducts (to alveoli).
. Make a rough sketch of the histology of the alimentary canal as shown in Figure 23.5
*labeled top to bottom* -mucosa -submucosa -muscularis externa -adventitial serosa
Name each part of the small intestine and give its approximate length.
-Duodenum: 20-25 cm -Jejunum: 2.5 m -Ileum: 3.5 m
Label the anatomical structures of the oral cavity (Figure 23.8)
...
Study Table 23.2 as it is a great overview of the functions of all of the gastrointestinal organs!
...
Describe the 5 steps of sequence of excitation in the heart pacemaker.
1) SA node generates 75 impulses per minute, and is the pacemaker for the whole heart. 2) AV node receives the signal via the internodal pathway and sends the impulse down the interventricular septum slowly 3) AV bundle receives the impulse next, this is the only electrical connection between the atrium and the ventricles. 4) The Av bundle then branches into the left and right bundle branches which run along the interventricular septum toward the apex of the heart. 5) The long strands of cells and myofibrils form the subendocardial conducting network (purkinje fibers)
What is the difference between type I and type II alveolar cells?
A type I alveolar cell is a squamous epithelial cell of the alveoli, which constitute up to 97 percent of the alveolar surface area. These cells are about 25 nm thick and are highly permeable to gases. A type II alveolar cell is interspersed among the type I cells and secretes pulmonary surfactant, a substance composed of phospholipids and proteins that reduces the surface tension of the alveoli.
How is the heart influenced by chemical regulation?
Acetylcholine decreases heart rate, epinephrine accelerates heart rate.
Describe the four layers of the GI tract. See Figure 23.4
All segments of the GI tract are divided into four layers: the mucosa (epithelium, lamina propria, and muscular mucosae), the submucosa, the muscularis propria (inner circular muscle layer, intermuscular space, and outer longitudinal muscle layer), and the serosa
What is the role of the pharynx in digestion?
Also called the throat, your pharynx is the part of the digestive tract that gets the food from your mouth.
Describe the anatomical structures of the alveolar ducts, sacs and alveoli as shown in figure 22.10.
An alveolar duct is a tube composed of smooth muscle and connective tissue, which opens into a cluster of alveoli. An alveolus is one of the many small, grape-like sacs that are attached to the alveolar ducts. An alveolar sac is a cluster of many individual alveoli that are responsible for gas exchange.
What is coronary circulation and how does it differ from regular circulation?
Coronary circulation is the blood flow that supplies oxygenated blood to the myocardium of the heart. This differs from regular circulation because the blood does not leave the heart to the rest of the body.
Describe the structure and function of the capillary bed.
Capillary beds are networks of small blood vessels which connect veins and arteries. The walls of capillaries are very thin which allows for the exchange of gases and nutrients, that way oxygenated blood from arteries is transferred to veins through capillary beds and all of the needed nutrients/oxygen is absorbed.
How are oxygen and carbon dioxide transported in the blood?
Carbon dioxide is carried physically dissolved in the blood, chemically combined to blood proteins as carbamino compounds, and as bicarbonate. Oxygen is transported both physically dissolved in blood and chemically combined to the hemoglobin in the erythrocytes.
What are arrhythmias and what causes them?
Arrhythmias are irregular heart rhythms, and are caused by defects in the intrinsic conduction system.
What is the general structure of arteries, veins and capillaries?
Arteries and veins both have tunics, which include the tunica media, tunica intima, and tunica externa. Capillaries are made up of a basement membrane and endothelial cells.
Discuss of a typical capillary bed as depicted in Figure 19.4.
Arterioles and venules connect through branches called terminal arterioles and postcapillary venules which branch out to form capillary beds.
How does the tissue composition change as you move down the bronchial tree?
As the branching continues through the bronchial tree, the amount of hyaline cartilage in the walls decreases until it is absent in the smallest bronchioles. As the cartilage decreases, the amount of smooth muscle increases.
Describe pressure relationships in the thoracic cavity (reference Figure 22.14).
As volume decreases, pressure increases and vice versa (Figure 1). The relationship between gas pressure and volume helps to explain the mechanics of breathing. There is always a slightly negative pressure within the thoracic cavity, which aids in keeping the airways of the lungs open.
How does high altitude affect respiration?
At high altitude, there is less oxygen in the air that you breathe. This means that all of the blood from all areas of the lungs, is relatively short on oxygen or hypoxic. Unfortunately, the lungs still respond to the shortage of oxygen in the same way: by tightening the blood vessels.
What is functional syncytium?
Beginning with the pacemaker cells, the intercalated discs allow for a wave of contraction during systole, which is a syncytium.
Trace the blood flow through the heart - with 14 steps.
Beginning with the pulmonary circuit, blood flow begins by returning to the heart by way of the superior vena cava into the right atrium. From there it is pumped through the tricuspid valve into the right ventricle. It is then pumped through the pulmonary valve, then into the pulmonary trunk and into the lungs to be oxygenated. It returns to the heart by the pulmonary veins, and flows into the left atrium. It then is pumped through the bicuspid valve and into the left ventricle. It then flows through the aortic valve into the aortic artery and is then pumped through the entire body.
Define the following terms: blood flow, blood pressure, resistance? What is the relationship between them?
Blood flow refers to the movement of blood through vessels, and tissues, blood pressure refers to the pressure of blood against the walls of the blood vessel, resistance is the force which the blood flow must overcome to push through a blood vessel such as diameter.
Is blood pressure in capillaries high or low? Explain.
Blood pressure in capillaries is higher than that of veins and lower than that of arteries. This is because the blood must move freely from arteries into capillary beds, however must slow down for gas exchange/nutrient absorption to occur before the blood moves into the veins.
Discuss at least 4 examples of cardiac imbalance of cardiac output.
Coronary atherosclerosis is fatty build up that clogs the heart arteries, persistent high blood pressure is high blood pressure in the chambers, multiple myocardial infarctions is the effects of multiple heart attacks, and dilated cardiomyopathy is characterized by the ventricles stretching and becoming flabby.
Explain the flow chart of digestion and absorption of food as outlined in Fig 23.36 to your best friend (this Figure is really good for studying!]
By the process of digestion, our body break down the food and liquids that we eat into smaller parts to nourish cells and provide energy. Various steps of digestive system in are: 1. When we chew the food in mouth,the saliva that present in our mouth helps to break the food into small pieces and starts digesting carbohydrates. 2. The broken and chewed food from saliva moves through a pipe called esophagus which connect the mouth to stomach. 3. In stomach, the food is stored and this store food is further broken down by acid and powerful enzymes that present in our stomach and from stomach food moves into the small intestine. 4. Most of the nutrients are absorbed in small intestine, in here food is broken down more by enzymes which is released from the pancreas and bile from the liver. Anything which left in the small intestine moves to the large intestine which is known as colon. 5. The colon is 5-7 foot long tube which connect the small intestine to the rectum. 6. Rectum play an important role in processing waste. 36 hours are required for stool or waste to go throughout the colon and exit the rectum through anus.
What are some of the major factors affecting respiration in humans?
Chemical- carbon dioxide, hydrogen ions and oxygen levels are the most important factors that regulate respiration.
What is echocardiography and when would doctors use this?
Echocardiography is the recording of electrical impulses through the heart, doctors use this to determine if the patient's heart rhythm is normal.
Why are arteries elastic and muscular? Which are which?
Elastic arteries are closest to the heart, and this helps them handle constant heavy flow of blood from the heart. Muscular arteries have smooth muscle to help maintain normal blood pressure in the artery.
Why is expiration considered a passive process in healthy individuals?
Expiration is typically a passive process that happens from the relaxation of the diaphragm muscle (that contracted during inspiration). The primary reason that expiration is passive is due to the elastic recoil of the lungs.
Why can't tetanic contractions occur in cardiac muscles?
If the heart were to contract tetanically it would be unable to relax and fill which would make it useless as a pump.
Describe autonomic innervation of the heart as shown in Fig. 18.14.
In the medulla oblongata, the vagus nerve is a parasympathetic nerve which decreases heart rate by sending signals to the SA and AV nodes in the heart. The medulla oblongata then sends interneurons to the thoracic spinal chord which uses the sympathetic trunk ganglion to send sympathetic neurons to the heart in order to increase heart rate/force of contraction.
What is the role of the larynx in digestion?
In the process of swallowing, the larynx plays an important role in the direction of food into the esophagus.
What types of teeth do humans have and why?
Incisors - Your incisors are eight teeth in the front center of your mouth (four on both bottom and top). These are typically the first adult teeth that a child will get, coming in when the child is between six and eight years old. Incisors are the teeth that you use to bite into your food. Canines - Your canines are the next teeth that develop in your mouth. You have four of them and they are your sharpest teeth, used for tearing apart food. Premolars - Premolars are used for tearing and crushing food. Unlike your incisors and canines, premolars have a flat biting surface. You have eight premolars in total. Molars - Your molars are your largest teeth. Their function is similar to that of the premolars, to grind, tear, and crush food. Molars have a large flat biting surface which makes them perfect for this job.
Explain the difference between the following terms in relation to the digestive system: ingestion, propulsion and mechanical breakdown.
Ingestion is entry of the food into the alimentary canal through the mouth. propulsion is the movement of food through the digestive tract. Mechanical breakdown is a purely physical process that does not change the chemical nature of the food, but makes it smaller to increase surface area and mobility
What is meant by internal respiration, as opposed to external respiration?
Internal respiration involves gas exchange between the bloodstream and tissues, and cellular respiration. Gas exchange in tissues is a result of tissue surface area, gas partial pressure gradients, and the blood perfusion of those tissues. External respiration refers to the process of exchanging oxygen and carbon dioxide in the lungs, gills, or other tissues exposed to the external environment.
What are the major coronary arteries? Veins?
Left coronary artery, left anterior descending artery, left circumflex artery, posterior descending artery, intermediate artery, right coronary artery, posterior descending artery. The coronary sinus, the anterior intraventricular vein, large marginal vein, posterior veins of the left ventricle, posterior interventricular vein.
Describe the anatomical relationships of the organs in the thoracic cavity, as shown in Figure 22.12.
It contains the lungs, the middle and lower airways—the tracheobronchial tree—the heart, the vessels transporting blood between the heart and the lungs, the great arteries bringing blood from the heart out into general circulation, and the major veins into which the blood is collected for transport back to the heart. The organs of the thorax include the thymus gland, the breasts, the heart, the lungs, the tracheobronchial tree and the pleurae. The thymus gland is located in the superior mediastinum of the thoracic cavity but may also extend into the neck.
What is mastication and where does this occur?
Mastication (chewing), in which food is crushed and mixed with saliva to form a bolus for swallowing, is a complex mechanism involving opening and closing of the jaw, secretion of saliva, and mixing of food with the tongue.
What digestive processes occur in the mouth?
Mechanical digestion begins in the mouth as the food is chewed.
Where does chemical digestion occur and where does mechanical digestion occur?
Mechanical digestion begins in the mouth as the food is chewed. Chemical digestion involves breaking down the food into simpler nutrients that can be used by the cells. Chemical digestion begins in the mouth when food mixes with saliva.
How are peristalsis and segmentation used by the digestive system to help break down food? What are each of their roles? See Figure 23.3
Peristalsis and segmentation control the movement and mixing of chyme through the small intestine. As in the esophagus and stomach, peristalsis consists of circular waves of smooth muscle contractions that propel food forward. Segmentation helps to mix food with digestive juices and facilitates absorption.
What role does peristalsis play in propulsion?
Peristalsis is primarily found throughout the gastrointestinal tract and is the involuntary propulsion of food. This movement begins in the pharynx, once a food bolus is formed, and ends in the anus. Along with segmentation or mixing of food, peristalsis is an essential part of providing the body with nutrients
Explain pulmonary circulation of the lungs to your kid brother who is in the 7th grade.
Pulmonary circulation moves blood between the heart and the lungs. It transports deoxygenated blood to the lungs to absorb oxygen and release carbon dioxide. The oxygenated blood then flows back to the heart
What are the main digestive processes in the stomach?
Propulsion, mechanical breakdown, digestion, and absorption
Discuss pulmonary and systemic circulation as depicted by Figure 19.3. [to your grandma]
Pulmonary circulation is the process in which blood returning to the heart becomes oxygenated again after giving the oxygen to all of the body's tissues. The blood flows into the heart's right atrium through the pulmonary veins. Then it flows through the tricuspid valve into the right ventricle, where it then flows through the pulmonary valve into the pulmonary trunk and through the lungs where it is then oxygenated. After being oxygenated, the systemic circuit begins, the blood returns to the heart to be pumped to the rest of the body through the left pulmonary veins into the left atrium. Then it goes through the mitral (bicuspid) valve into the left ventricle, which pumps the blood through the aortic valve into the aortic arch, and to the rest of the body.
Explain pulmonary ventilation to your parents over dinner.
Pulmonary ventilation is commonly referred to as breathing. It is the process of air flowing into the lungs during inspiration (inhalation) and out of the lungs during expiration (exhalation).
How does pulmonary respiration (ventilation) differ from internal respiration?
Pulmonary ventilation is the MOVEMENT of air in and out of the lungs and internal respiration is the actual exchanges of gases between the blood and tissue cells.
Discuss the four processes of respiration (as shown in Figure 22.1)
Pulmonary ventilation is the movement of air into and out of the lungs (breathing). External respiration is the exchange of O2 (loading) and CO2 (unloading) between blood and alveoli (air sacs). Transport of respiratory gases between lungs and tissues. Internal respiration is gas exchange between blood and tissue cells.
What is fibrillation and what are some common causes?
Rapid and uncontrollable heart contractions, this can be caused by defects in the intrinsic conduction system.
Explain the muscular pump in relation to venous blood pressure [see Figure 19.9]
Skeletal muscles contract around a vein, which causes pressure on the vein which forces the blood in the area upwards. The force of the blood flow opens the valves in the vein and the blood is forced back towards the heart. The back flow if blood closes the valves to prevent the blood from flowing backwards.
What is meant by alveolar surface tension and what is the role of surfactant?
Surface tension draws fluid from capillaries to the alveolar spaces. Surfactant reduces fluid accumulation and keeps the airways dry by reducing surface tension.
Discuss the relative proportion of blood volume throughout the cardiovascular system as depicted by Figure 19.6.
Systemic veins and venules contain 60%, capillaries contain 5%. The heart contains 8%, pulmonary blood vessels contain 12%, and systemic arteries/arterioles contain 15% of the blood volume.
Define systole and diastole. Discuss the difference between systolic and diastolic pressure.
Systole is the contraction of cardiac muscle, and diastole is the relaxation of the heart. The amount of blood in the arteries when the heart beats is systolic pressure, while the amount of blood in the arteries while the heart is not pumping blood is diastolic pressure.
What is meant by innervation of the lungs, and why it this important?
The blood supply of the lungs plays an important role in gas exchange and serves as a transport system for gases throughout the body. In addition, innervation by the both the parasympathetic and sympathetic nervous systems provides an important level of control through dilation and constriction of the airway.
Why is the submucosa of the trachea lined with c-shaped cartilaginous rings?
The cartilaginous rings are C-shaped to allow the trachea to collapse slightly at the opening so that food can pass down the esophagus. The trachealis muscle connects the ends of the open part of the C-shaped rings and contracts during coughing, reducing the size of the lumen of the trachea to increase the air flow rate.
Explain what is meant by the "ceaselessly beating heart" and how that works.
The ceaselessly beating heart is the awareness of the fact that the heart is continuously beating without rest until we die. This is achieved by each factor of the cardiovascular system working to pump blood flow through the body continuously, which makes way for gas exchange and stimulus for the heart to beat.
Describe how the heart contracts as a unit.
The cells are connected by gap junctions which allow a wave of polarization to flow through the heart cell to cell.
What are the chordae tendineae? Describe the function.
The chordae tendineae anchor the atrioventricular valves to papillary muscles and prevent the valves from opening in the wrong direction.
Why do you get sleepy after eating a large meal?
The constant movement of chyme back and forward creates the illusion of the contents being massaged
When vascular smooth muscle contracts, what happens to the diameter of the blood vessel? What is this called?
The diameter decreases when the smooth muscle contracts, this is called vasoconstriction.
Describe the action potential initiation by pacemaker cells in three steps.
The first step is pacemaker potential which deals with the ion channels in the sarcolemma. The hyperpolarization in these cells causes an influx of Na+ and the membrane interior becomes less negative. The next step is depolarization which is when Ca2+ channels open allowing explosive entry of Ca2+ that produces the rising phase of action potential and reverses the membrane potential. The last step is repolarization, which is when Ca2+ channels become inactive and the falling phase of the action potential and repolarization reflect opening of K+ channels and K+ efflux from the cell.
What is the "ninth" cartilage of the larynx, and why is it important for respiration?
The flap-like structure that allows the larynx to "control" whether air or food passes is the epiglottis. It is the ninth cartilage of the larynx and extends from the tongue's posterior aspect to where it is anchored, on the anterior rim of the thyroid cartilage. When swallowing, the larynx rises and the epiglottis presses downward, partially covering the opening into the larynx to help prevent foods and liquids from entering the air passages.
What is the gall bladder and what it its function in digestion?
The gall bladder is a thin-walled muscular sac that stores bile
What are the major components/structures associated with coronary circulation?
The great cardiac vein, the middle cardiac vein, the lesser cardiac veins, the anterior cardiac veins, the right atrium, and the coronary sinus.
Discuss the hierarchy of the blood vessels in the human body.
The largest vessels are the arteries, then the veins, then arterioles, then the smallest is capillaries.
Describe the basic anatomy of the larynx?
The larynx is located in the anterior compartment of the neck, suspended from the hyoid bone, and spanning between C3 and C6. It is continuous inferiorly with the trachea, and opens superiorly into the laryngeal part of the pharynx. Larynx, also called voice box, a hollow, tubular structure connected to the top of the windpipe (trachea)
What other functions does the larynx have?
The larynx serves to protect the lower airways, facilitates respiration, and plays a key role in phonation. In humans the protective and respiratory functions are compromised in favor of its phonatory function.
What role does the larynx play in respiration?
The larynx, commonly called the voice box or glottis, is the passageway for air between the pharynx above and the trachea below.
Why is the left ventricle thicker than the right? And why is the aorta so large?
The left ventricle is apart of the systemic circuit and is responsible for pumping blood to the entire body, while the right ventricle only pumps to the lungs which is why the left ventricle is thicker than the right. The aorta is so large because it is the first artery which branches from the heart to the rest of the body.
What structures are associated with the lower respiratory system (see Table 22.2)?
The lower respiratory system, or lower respiratory tract, consists of the trachea, the bronchi and bronchioles, and the alveoli, which make up the lungs. These structures pull in air from the upper respiratory system, absorb the oxygen, and release carbon dioxide in exchange.
Describe the role of peristalsis in the esophagus and in deglutination.
The main role of the esophagus is to propel swallowed food or fluid into the stomach
What is the major functional organ of the digestive system? Explain
The major organs of the digestive system are the stomach and intestine.
. Discuss the microscopic structure of the esophagus (See Figure 23.13)
The microscopic structure of esophagus. The lining of the esophagus consists of more than one layer of cells, and the surface layer consists of flat or squamous cell. It's a good example of stratified squamous epithelium (SS). In a stratified epithelium, the shape and height of the cells usually vary from layer to layer, but only the shape of the cells that form the surface layer is used in classifying the epithelium. The wall of the esophagus contains the smooth muscle and the skeletal muscle.
Discuss the role of the mouth in ingestion.
The mouth is the beginning of the digestive tract. In fact, digestion starts before you even take a bite. Your salivary glands get active as you see and smell that pasta dish or warm bread. After you start eating, you chew your food into pieces that are more easily digested.
Why is the tongue associated with so many muscles?
The tongue is really made up of many groups of muscles. These muscles run in different directions to carry out all the tongue's jobs. The front part of the tongue is very flexible and can move around a lot, working with the teeth to create different types of words.
What is the difference between the tricuspid and biscuspid valves, and why do they have these differences?
The tricuspid valve is made of three cusps and is located in between the right atrium and right ventricle, while the bicuspid valve is made of two cusps and is located in between the left atrium and left ventricle.
Describe the three layers that typically form the wall of a blood vessel, and state the function of each.
The tunica intima serves as a barrier between blood and the vessel, tunica media aids with vasoconstriction/vasodilation, and the tunica externa serves as protection and structural support
Which layer of the blood vessel wall do these nerves innervate?
The tunica media.
What are some major respiratory diseases that can cause disability and death (see Section 22.10)
The two main conditions contributing to death and disability are asthma and chronic obstructive pulmonary disease
Briefly describe voice production in humans.
The vocal folds (vocal cords) are attached within the larynx to the largest of the laryngeal cartilages known as the thyroid cartilage or "Adam's apple". The vocal folds produce sound when they come together and then vibrate as air passes through them during exhalation of air from the lungs. This vibration produces the sound wave for your voice. In order for the sound to be clear and not raspy or hoarse, the vocal folds must vibrate together symmetrically and regularly. The rate of vibration determines the pitch of the voice.
Explain this statement in relation to respiration: Volume changes cause pressure changes, which cause air to move.
The volume changes result in pressure changes, which lead to the flow of gases to equalise the pressure. When gases move from an area of high pressure to an area of low pressure, this is known as 'bulk flow'. During a breathing cycle, air moves in and out of the lungs by bulk flow. The respiratory muscles are responsible for the changes in the shape and volume of the chest cavity that cause the air movements in breathing.
Describe the microscopic anatomy of cardiac muscle?
There are long fibrous cells which resemble a rectangular shape and are connected by intercalated discs.
What are the three trunks of the aorta, and why do we have all three.
There are the brachiocephalic trunk, the left common carotid artery, and the left subclavian artery. The head, neck, and arms all get their oxygenated blood from these branches.
What are the nasal conchae and meatuses and what are their purposes?
There are three conchae - inferior, middle and superior. They increase surface area and inspired air. They are curved nasal bones. There are four meatuses: Inferior meatus, Middle meatus, Superior meatus, Spheno-ethmoidal recess. Drainage of three of the paranasal sinuses; the maxillary, frontal, and front (anterior) ethmoid sinuses. Airflow through the paranasal sinuses which creates the tones of our voices.
How exactly do pacemaker cells trigger action potentials throughout the heart?
They depolarize spontaneously which triggers the depolarization of all other cardiac cells.
What is the function of the heart auricles.
They help their atriums hold more blood volume.
How do 1). Thickness and 2). Surface Area of the respiratory membrane affect breathing?
This large surface area is necessary to process the huge amounts of air involved in breathing and getting oxygen to your lungs. Overall thickness of the respiratory membrane in some areas is as little as 0.2 -0.6 micrometer. The total quantity of blood in the capillaries of the lungs at any instant is 60 - 140 ml •The average diameter of the pulmonary capillaries is only about 5 μ, which means that red blood cells must squeeze through them.
What is the primary function of the upper respiratory system?
To move air toward the lungs while warming, moistening, and filtering it.
What are vocal cords and how do they work? Describe them anatomically.
either of two folds of mucous membrane that extend across the interior cavity of the larynx and are primarily responsible for voice production. Sound is produced by the vibration of the folds in response to the passage between them of air exhaled from the lungs.
Describe the movement of the diaphragm during inspiration and expiration.
Upon inhalation, the diaphragm contracts and flattens and the chest cavity enlarges. This contraction creates a vacuum, which pulls air into the lungs. Upon exhalation, the diaphragm relaxes and returns to its domelike shape, and air is forced out of the lungs.
What is the difference between vasoconstriction and vasodilation?
Vasoconstriction is a process which causes the blood vessel to become more narrow, while vasodilation causes the vessel to become wider
What is meant by ventilation-perfusion coupling (see Figure 22.23).
Ventilation perfusion coupling means that more blood flows past functional alveoli than past nonfunctional alveoli.
What is the role of the intercostal muscles during ventilation?
When you inhale: the internal intercostal muscles relax and the external intercostal muscles contract, pulling the ribcage upwards and outwards. the diaphragm contracts, pulling downwards. lung volume increases and the air pressure inside decreases.
Describe the sliding filament theory.
Within a sarcomere actin and myosin slide along each other to facilitate contraction, this process requires ATP.
What is a sphincter and why are they so important for the digestive system?
a ring-like muscle at the bottom of your esophagus, called the lower esophageal sphincter, has to relax to let the food in. The sphincter then contracts and prevents the contents of the stomach from flowing back into the esophagus.
Explain the following statements to your parents over dinner:
a. Digestive activity is provoked by a range of mechanical and chemical stimuli b. Effectors of digestive activity are smooth muscles and glands c. Neurons and hormones control digestive activity These three statements are the concepts that regulate the GI activity
In relation to the alimentary canal, describe each of the following and their major components: See Figure 23.5
a. Intrinsic nerve plexuses: The inner plexus is the main control for GI secretion and local blood flow. The myenteric plexus extends throughout the entire length of the gut as a linear chain of interconnected neurons. Lying within the intestinal smooth muscle, the myenteric plexus focuses on muscle control. b. Mucosa: The mucosa is the innermost layer of the GI tract. It is made up of three layers: the epithelium, lamina propria, and muscularis mucosae. The mucosa surrounds the lumen, or open space within the digestive tube. This layer comes in direct contact with digested food (chyme). c. Submucosa: The submucosa is of dense irregular connective tissue and may contain some esophageal mucous glands, vessels and nerve fibers, and the ganglion cells and nerve fibers of Meissner's plexus. The muscularis externa is a smooth muscle in most regions of the alimentary canal but the esophagus is unique. d. Muscularis externa: The muscularis externa is responsible for segmental contractions and peristaltic movement in the GI tract. These muscles cause food to move and churn together with digestive enzymes down the GI tract. The muscularis externa consists of an inner circular layer and a longitudinal outer muscular layer. e. Serosa: The serosa is the portion of the alimentary canal superficial to the muscularis. Present only in the region of the alimentary canal within the abdominal cavity, it consists of a layer of visceral peritoneum overlying a layer of loose connective tissue.
What is the main function of each of these structures of the oral cavity?
a. Mouth- Eating and speaking b. Tongue- taste, mastication, swallowing, and speech c. Lips and cheek- holding food, speech, temperature and texture in foods d. Palate- The hard palate holds the root of the teeth. The soft palate pressed down for swallowing. e. Salivary glands- produce saliva, breaks down carbohydrates, lubricates the passage of food f. Teeth- breaking down (masticating) food, enabling us to pronounce words, and shaping the face
What is the function (and general structure) of the:
a. Rectum: penetrates the levator ani muscle of the pelvic floor and opens to the body exterior at the anus b. Anus- the end of the gastrointestinal tract; the opening and closing of the anal canal
10. What is the conducting zone, and what structures are part of this zone?
conducting zone consists of the nose, pharynx, larynx, trachea, bronchi, and bronchioles. These structures form a continuous passageway for air to move in and out of the lungs.
What is the structure and function of the soft palate?
The soft palate is moveable, consisting of muscle fibers sheathed in mucous membrane and is at the back of the roof. The main functions of the soft palate are to aid speech, swallowing, and breathing.
Explain the circular and spiral arrangement of the cardiac muscle bundles. Explain why this arrangement is important.
The spiral shape of the muscle fibers allow for a wringing affect during contraction of the heart.
Explain the major function of the stomach.
The stomach is a temporary storage tank. It serves as the holding area for infected food, the stomach continues the demolition job by degrading food both physically and chemically
What is the gross anatomy of the stomach? Make a sketch and label the major structures (See Figure 23.15)
The stomach lies in the upper left quadrant of the peritoneal cavity, nearly hidden by the liver and diaphragm. The adult stomach varies from 15 to 25 cm long and an empty stomach has a volume of 50 ml. A full stomach can hold about 4 L of food.
Making connections: What branch of the autonomic nervous system innervates blood vessels?
The sympathetic nervous system is responsible for innervating blood vessels.
How is the heart regulated by the autonomic nervous system?
The sympathetic nervous system releases chemical signals that accelerate heart rate in states on emergency.
Explain bronchial circulation of the lungs to your kid sister who is in the 8th grade.
the bronchial circulation supplies oxygenated blood to the tissue of the larger airways of the lung.
What specific part of the pharynx is associated with digestion and how?
the oropharynx and the laryngopharynx, are used for both breathing and digestion.
Describe the gross anatomy of the liver, including the four lobs, falciform ligament gallbladder, ligaments, major veins, and major arteries.
• Weighs about 3 pounds, shaped like a wedge, on the right side of the body midline than to the left, located under the diaphragm, and lies within the rib cage • There are 4 lobes: the right lobe, left lobe, caudate lobe, and quadrate lobe • Falciform ligament- separates the right and left lobes anteriorly and suspends the liver from the diaphragm • Round ligament- a fibrous remnant of the fetal umbilical vein • Hepatic artery proper and hepatic portal vein: enters the liver at the porta hepatitis
What are some homeostatic imbalances of the liver?
• hepatitis : inflammation of the liver, can be caused by alcohol, drugs, and wild mushrooms; constant liver infections • Non-alcoholic fatty liver disease: obesity and an increase insulin resistance are associated with abnormal lipid metabolism • Cirrhosis: results from severe chronic hepatitis due to chronic alcoholism