Term
| How large is the human heart? |
|
Definition
|
|
Term
| How much does the heart weigh? |
|
Definition
| 250-350 grams, less than a pound |
|
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Term
| Where is the heart located? |
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Definition
|
|
Term
| What is the fibrous pericardium? |
|
Definition
| The superficial, outer covering of the heart |
|
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Term
| What is the fibrous pericardium composed of (tissue type)? |
|
Definition
|
|
Term
| What are the functions of the fibrous pericardium? |
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Definition
| To protect the heart, anchoring to surrounding structures including the diaphragm and great vessels, also to prevent overfilling with blood. |
|
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Term
| What is the serous pericardium? |
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Definition
| The inner, thin, slippery serous membrane, made up of two layers. |
|
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Term
| What are the two layers of the serous pericardium? |
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Definition
| The parietal layer (outer), and visceral layer (also known as the epicardium) which is tightly attached to the wall of the heart. |
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Term
| What is the pericardial cavity?` |
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Definition
| The space between the two layers of the serous pericardium, contains serous fluid so that the membranes glide easily during heart activity. |
|
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Term
| What are the three layers of the heart wall? |
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Definition
| The epicardium, myocardium, and endocardium. |
|
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Term
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Definition
| The superficial layer surrounding the heart muscle (epicardium is the visceral layer of the serous pericardium). Often infiltrated with fat. |
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Term
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Definition
| Sheets of endothelium that cover the entire inside of the heart changes and insides of vessels. |
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Term
| What type of tissue is endocardium composed of? |
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Definition
| Endothelium; i.e. squamous epithelium. |
|
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Term
| How are arteries and veins differentiated? |
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Definition
| Arteries carry blood away from the heart, veins carry blood towards the heart. |
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Term
| What is another name for the atrioventricular groove? |
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Definition
|
|
Term
| What is the atrioventricular groove? |
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Definition
| Encircles the junction of atria and ventricles. |
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Term
| What is the anterior interventricular sulcus? |
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Definition
| Cradles the anterior interventricular artery, marks anterior position of the septum between the left and right ventricles. |
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Term
| What is the posterior interventricular sulcus? |
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Definition
| Continuation of the anterior interventricular sulcus, a landmark on the posterior surface of the heart. |
|
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Term
| What type of muscle is found in the atria? |
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Definition
|
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Term
| What are the function of the heart's auricles? |
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Definition
| Increase volume of the heart. |
|
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Term
| What is the intraatrial septum? |
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Definition
| A shallow depression in the atria (fossa ovalis). |
|
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Term
| What is the fossa ovalis? |
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Definition
| Where the foramen ovale was present in the fetal heart. |
|
|
Term
| What is the foramen ovale? |
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Definition
| An opening in the fetal heart that directly connects two atria thus allowing blood to bypass the pulmonary circuit to the fetal lungs. |
|
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Term
| What three vessels enter the right atria? |
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Definition
| The superior and inferior vena cava, and the coronary sinus. |
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Term
| Where does blood come from that flows from the two vena cava into the right atrium? |
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Definition
| Superior vena cava blood comes from an area superior to the diaphragm, inferior vena cava blood comes from areas below the diaphragm. |
|
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Term
| What blood comes through the coronary sinus? |
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Definition
| Blood from the myocardium. |
|
|
Term
| What divides the right and left ventricles of the heart? |
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Definition
| The interventricular septum. |
|
|
Term
| Where is the right ventricle located? |
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Definition
| The anterior part of heart. |
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Term
| Where is the left ventricle located? |
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Definition
| The posterior, more inferior portion of heart. |
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Term
| What type of muscle is found in the ventricles? |
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Definition
| Papillary muscle and trabeculae carneae. |
|
|
Term
| What are papillary muscles? |
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Definition
| Muscular bundles that project into the ventricular cavity, connect to the chordae tendonae. |
|
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Term
| Where does the right ventricle pump into? |
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Definition
|
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Term
| Where does blood in the pulmonary trunk travel to, and what is its composition? |
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Definition
| The blood travels to the lungs, it was deoxygenated until this point. |
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|
Term
| Where does blood from the left ventricle flow? |
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Definition
| Into the aorta to be transported to the rest of the body. |
|
|
Term
| What is the path of the pulmonary circuit? |
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Definition
| Right atrium -> right ventricle -> pulmonary trunk -> pulmonary arteries -> lungs -> pulmonary veins -> left atrium |
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Term
| Where are the general oxygen quantities of veins and arteries opposite? |
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Definition
| In the pulmonary circuit. |
|
|
Term
| What is the general flow of the systemic circuit? |
|
Definition
| Left atrium -> left ventricle -> aorta -> vessels throughout body -> superior or inferior vena cava -> right atrium |
|
|
Term
| What is the general path of the coronary circuit? |
|
Definition
| Ascending aorta -> left or right coronary artery -> capillaries in myocardium -> cardiac veins -> coronary sinus -> right atrium |
|
|
Term
|
Definition
| Connections between 2 or more branches of arteries that supply the same region with blood. This provides alternate routes for blood to reach a particular region. There are many of these around the heart. |
|
|
Term
| Where do the right and left coronary arteries arise from? |
|
Definition
|
|
Term
| Where do the right and left coronary arteries run? |
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Definition
| Along the atrioventricular groove of the heart. |
|
|
Term
| Where does the left coronary artery run and how does it divide? |
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Definition
| Runs toward the left side of the heart and divides into the anterior interventricular artery and the circumflex artery. |
|
|
Term
| What is the anterior interventricular artery? |
|
Definition
| Supplies the interventricular septum and anterior side of the ventricles with blood. |
|
|
Term
| Where does the anterior interventricular artery arise from? |
|
Definition
| From the left coronary artery, which arises from the base of the aorta. |
|
|
Term
| Where does the right coronary artery run and how does it divide? |
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Definition
| Courses to the right side of the heart and divides into the marginal arter and posterior interventricular artery. |
|
|
Term
| What is the circumflex artery? |
|
Definition
| Supplies the left atrium and posterior wall of the left ventricle. |
|
|
Term
| What is the posterior interventricular artery and where does it arise from? |
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Definition
| Supplies the posterior ventricular walls, arises from the right coronary artery. |
|
|
Term
| What is the marginal artery and where does it arise from? |
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Definition
| Supplies blood to the lateral right side of the heart, arises from the right coronary artery. |
|
|
Term
| Cardiac veins join together to form what? |
|
Definition
| The coronary sinus, which flows into the right atrium. |
|
|
Term
| What are the branches of the coronary sinus? |
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Definition
| Great, middle, and small cardiac veins. |
|
|
Term
| What is the great cardiac vein? |
|
Definition
| Found in anterior interventricular sulcus. |
|
|
Term
| What is the middle cardiac vein? |
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Definition
| Lies in the posterior interventricular sulcus. |
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|
Term
| What is the small cardiac vein? |
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Definition
| Runs along the heart's right inferior margin. |
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|
Term
| When the heart is relaxed, what do the atrioventricular valves do? |
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Definition
| Hang limply open into the ventricles. |
|
|
Term
| What is the right AV valve? |
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Definition
| The tricuspid valve, with 3 flexible cusps. |
|
|
Term
| What is the left AV valve? |
|
Definition
| The biscuspid valve, also known as the mitral valve. |
|
|
Term
| What are the chordae tendineae? |
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Definition
| "Tendonous cords", aka "heart strings", tiny white collagen cords attached to each of the AV valve cusps. Anchor the cusps to paillary muscle protruding from ventricle walls. |
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Term
| What are the two semilunar valves of the heart and what are their structure? |
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Definition
| The pulmonary and aortic semilunar valves, each has 3 pocket like cusps, resemble a "half moon". |
|
|
Term
| Why is cardiac muscle striated? |
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Definition
| Allows contraction by sliding filament mechanism. |
|
|
Term
| What is the connective tissue between cardiac cells? |
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Definition
| The endomysium, dense with many capillaries to provide blood flow. |
|
|
Term
| What are the functions of desmosomes in cardiac cells? |
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Definition
| Interlock adjacent cardiac cells. |
|
|
Term
| What is the function of gap junctions in cardiac cells? |
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Definition
| Allow ions to pass freely cell to cell to allow depolarization. |
|
|
Term
| The fact that the heart cells can beat in unison is known as what? |
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Definition
|
|
Term
| What is the lack of oxygen known as? |
|
Definition
|
|
Term
| How are heart cells stimulated? |
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Definition
| The are self-stimulating, initiating their own depolarization. |
|
|
Term
| How long is the absolute refractory period of a cardiac cell? |
|
Definition
| 250 ms, as opposed to 1-2 ms in skeletal muscle. |
|
|
Term
| Why do cardiac cells have such a long absolute refractory period? |
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Definition
| Prevents tetanic (high frequency) contractions that would stop pumping action. |
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|
Term
| In the cardiac action potential, influx of Na+ ion causes what? |
|
Definition
| Positive feedback, enabling more contractions. |
|
|
Term
| What part of the cardiac cell releases Ca++? |
|
Definition
| The sarcoplasmic reticulum. |
|
|
Term
| What does Ca++ provide signaling for? |
|
Definition
| Provides signaling for sliding filaments. |
|
|
Term
| When Ca++ channels close, what happens in the cell? |
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Definition
| The K+ channels open, and allow the RMP to be restored. |
|
|
Term
| The coordinated system of the heart is a function of what two things? |
|
Definition
| Gap junctions and the intrinsic conduction system. |
|
|
Term
| What is the chief characteristic of autorhythmic cells of the heart? |
|
Definition
| They have an unstable resting potential, enabling easy depolarization. In fact they are constantly depolarizing, drifting towards threshold. |
|
|
Term
| How often is the sinoatrial node depolarized? |
|
Definition
| Approximately 75 times each minute. |
|
|
Term
| Where is the fastest depolarization rate in the heart? |
|
Definition
|
|
Term
| What is another name for the characteristic pace maker rhythm? |
|
Definition
|
|
Term
| Where is the atrioventricular valve located? |
|
Definition
| The inferior portion of the interatrial septum just above the tricuspid valve. |
|
|
Term
| Why is the AP (impulse) delayed slightly at the AV node? |
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Definition
| In order to allow the atria to finish completely contracting before the ventricles contract. |
|
|
Term
| Where does the impulse in the heart travel to after the atrioventricular node? |
|
Definition
| The Bundle of His (AV bundle). |
|
|
Term
| Where does the bundle of His run? |
|
Definition
| Through the superior part of the interventricular septum. |
|
|
Term
| What is unique about the Bundle of His? |
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Definition
| It is the only connection between the atria and ventricles. |
|
|
Term
| What are the Purkinje fibers? |
|
Definition
| Long strands of barrel shaped cells, complete the pathway through the interventricular septum, penetrate into the heart apex, and turn superiorly into ventricular walls. |
|
|
Term
| What do the Purkinje fibers initiate? |
|
Definition
| Directly supplies papillary muscles to start the closure of AV valves. |
|
|
Term
|
Definition
| Uncoordinated AV contractions, fibrillation. |
|
|
Term
|
Definition
| No conduction through the AV node, need an artificial pacemaker to carry impulses to ventricles. |
|
|
Term
| What are the three distinguishing waves of an EKG? |
|
Definition
|
|
Term
| What is the P wave of an EKG? |
|
Definition
| First wave, small, lasting approximately 0.08 seconds. It is the atrial depolarization wave from the SA node through the atria. |
|
|
Term
| What is the QRS complex wave? |
|
Definition
| Average duration of 0.08 seconds, results from ventricular depolarization and precedes ventricular contraction. Shape reveals the different shape of the two ventricles and the time required for each to depolarize. |
|
|
Term
| What is the T wave in an EKG? |
|
Definition
| Final wave, lasts about 0.16 seconds. Caused by ventricular repolarization, slower than depolarization. |
|
|
Term
| Why is atrial repolarization not shown in an EKG? |
|
Definition
| Because it is obscured by the QRS complex because it takes place during ventricular excitation. |
|
|
Term
| What occurs during the P-Q interval? |
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Definition
| Atria repolarize, beginning of ventricular excitation. |
|
|
Term
| What occurs during the Q-T interval? |
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Definition
| The ventricles finish depolarizing, and begin repolarizing. |
|
|
Term
| What does it mean if there is no P wave? |
|
Definition
|
|
Term
| What does it mean if there are more P waves than QRS waves? |
|
Definition
| Heart block, ventricles no longer paced by AV node. |
|
|
Term
| What does it mean if there is an enlarged R wave? |
|
Definition
|
|
Term
| What does it mean if there is a flattened T wave? |
|
Definition
|
|
Term
| What does a prolonged Q-T interval mean? |
|
Definition
| A repolarization abnormality, presents a risk of ventricular arrhythmia. |
|
|
Term
| What occurs during mid-late diastole? |
|
Definition
| Ventricles fill, blood flows through the AV valve, atrial pressure rises, maximum pressure. |
|
|
Term
| What occurs during ventricular systole? |
|
Definition
| Atria relax, AV valves closed, ventricles contract |
|
|
Term
| What occurs during early diastole? |
|
Definition
| Isovolumetric relaxation (brief, following T wave), ventricles relax, atria filling, AV valves reopen and blood begins to flow into ventricles |
|
|
Term
| What occurs during the lub sound of the heart? |
|
Definition
| The the AV valves snap shut, indicating the onset of ventricular systole. |
|
|
Term
| What occurs during the dub sound of the heart? |
|
Definition
| Immediately after the ventricles contract and ventricular diastole begin, the semilunar valves snap shut. |
|
|
Term
|
Definition
| Cardiac output, defined as the stroke volume times the heart rate. |
|
|
Term
| What is the typical stroke volume? |
|
Definition
|
|
Term
| What is the typical adult volume? |
|
Definition
| 5 liters throughout the body |
|
|
Term
| When does the sympathetic nervous system govern the heart? |
|
Definition
| During times of flight or fight. |
|
|
Term
| What does the sympathetic nervous system release in times of flight or fright? |
|
Definition
| Norepinephrine at the cardiac synapses. |
|
|
Term
| What does the norepinephrine bind to and how does it function? |
|
Definition
| Binds to adergenic receptors in the heart, causing the threshold to be reached more quickly and enhances Ca++ entry to stimulate contractile cells. |
|
|
Term
| How does the parasympathetic nervous system govern the heart? |
|
Definition
| Activated in times of rest, grief, severe depression, etc. |
|
|
Term
| What does the parasympathetic nervous system release when governing the heart? |
|
Definition
|
|
Term
| What does acetylcholine bind to in the heart? |
|
Definition
| Muscarinic receptors, results in the hyperpolarization of the cardiac cells by opening K+ channels. |
|
|
Term
| What hormones regulate the heart? |
|
Definition
| Epinephrine and thyroxine. |
|
|
Term
| What does epinephrine do to the heart? |
|
Definition
| Released by the adrenal gland, enhances heart rate & contractility. |
|
|
Term
| What does thyroxine do to the heart? |
|
Definition
| Released by the thyroid gland, increases heart rate, metabolic rate, and body heat. |
|
|
Term
| What does increased Na+ do to the heart action potential? |
|
Definition
| Inhibits Ca++ transport, blocks heart contraction. |
|
|
Term
| What does increased K+ do to the heart? |
|
Definition
| Disrupts depolarization, may cause heart block and cardiac arrest. |
|
|
Term
| What is the ductus arteriosus? |
|
Definition
| An additional lung bipass between the pulmonary trunk and aorta in the fetus, is the ligamentum arteriosum in adults. |
|
|
Term
| What are the most abundant type of papillae? |
|
Definition
|
|
Term
| Where are the circumvallate papillae located? |
|
Definition
| Largest, fewest, back of tongue, taste buds on side. |
|
|
Term
| What are the basal cells of the taste buds? |
|
Definition
| Stem cells, give rise to new gustatory cells. |
|
|
Term
| What is the primary characteristic of gustatory receptor cells? |
|
Definition
| Microvilli/hairs that contact chemicals in food. |
|
|
Term
| What are the nerves that govern the gustatory pathway? |
|
Definition
| The facial nerve (VII), glossopharyngeal (IX), and vagus nerve (X). |
|
|
Term
| What portion of the tongue does the facial nerve govern? |
|
Definition
| The anterior 2/3 of the tongue, chorda tympani. |
|
|
Term
| What is the taste pathway? |
|
Definition
| Sensory nerve fibers synapse in the solitary nucleus of the medulla, to the thalamus, to the gustatory cortex of the parietal lobe. |
|
|
Term
| What type of cells line the roof of the nasal cavity? |
|
Definition
| Pseudostratified epithelium. |
|
|
Term
| Olfactory epithelium cover what areas of the nose? |
|
Definition
| The roof of the nasal cavity, the superior nasal concha in the nasal septum of the ethmoid bone. |
|
|
Term
| What type of neurons are olfactory receptors? |
|
Definition
| Bipolar neurons (60 day lifespan!). |
|
|
Term
| What is an apical dendrite? |
|
Definition
| Part of the olfactory receptor neuron, has olfactory cilia, which extend to increase surface area. |
|
|
Term
| What is the olfactory pathway? |
|
Definition
| Receptor, CN 1 (axons of receptors), olfactory bulbs, these synapse with mitral cells in glomeruli and axons specific for neurons with receptors specific for smell type send message, then passes through the olfactory tracts to the olfactory cortex, and into the subcortical structures. |
|
|
Term
|
Definition
| Refine, amplify, and relay signal. |
|
|
Term
| What occurs in the olfactory cortex? |
|
Definition
| Smells are interpreted and identified. |
|
|
Term
| What is a scientific name for eyelids? |
|
Definition
|
|
Term
|
Definition
| The medial and lateral angles of the eye |
|
|
Term
| What is the lacrimal caruncle? |
|
Definition
|
|
Term
| What is the palpebral conjunctiva? |
|
Definition
|
|
Term
| What is the bulbar conjunctiva? |
|
Definition
| Anterior surface of the eyeball. |
|
|
Term
| Where do the lacrimal glands lie? |
|
Definition
|
|
Term
| How do tears flow out of the eye? |
|
Definition
| Through the lacrimal canal, sacs, ducts, out through the inferior nasal meatus into and out of the nose. |
|
|
Term
|
Definition
| Lateral rectus controlled by CN VI (abducens), superior oblique controlled by IV (trochlear), and the rest are controlled by III, the occularmotor nerve. |
|
|
Term
| What is the anterior surface of the lens epithelium composed of? |
|
Definition
|
|
Term
| What are ciliary muscles? |
|
Definition
|
|
Term
| What are the three layers of the retina? |
|
Definition
| The pigmented layer, the neural layer, and the optic disc. |
|
|
Term
| What are the ciliary processes? |
|
Definition
| Contain capillaries that secrete fluid anteriorly. |
|
|
Term
| What are the interior chambers of the eye? |
|
Definition
| The vitreous humor of the posterior segment filled with glassy clear gel, and the anterior segment filled with aqueous humor. |
|
|
Term
| What does the posterior segment of the eye do? |
|
Definition
| Transmits light, supports posterior lens, and contributes to intraocular pressure. |
|
|
Term
| What is the vision pathway? |
|
Definition
| The optic nerve, optic chiasm, optic tracks, genigulate of thalamus, optic radiations in white matter, visual center in occipital lobe. |
|
|
Term
| What is the tensor tympani? |
|
Definition
| Arises from auditory tube to attach to malleus, a muscle. |
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