Human Anatomy OC 1 Flashcards
Which two genes are important in bronchial development?
FGF10 controls tip branching and elongation while TGF(beta)1 controls tip termination.
What is the structure of the Trachea?
It is composed, starting from the innermost layer, mucosa and lamina propria ( Loose CT) with the seromucous glands, Hyline cartilage and then a layer of dense CT called Adventitia. The Lamina Propria contains lymphocytes and the submucosa contains glands that are seromucous. Posteriorly we have a cartilaginous ring and the Trachealis muscle.
Where do bronchial arteries originate from and what are their variants?
Right bronchial arteries originate normally form the 5th or 6th posterior intercostal artery but in 36% of the cases they can originate elsewhere such as the 3th posterior intercostal artery or the subclavian artery. The left bronchial arteries originate from the aorta at the level T5 or T6. Type 1 is 1R and 2L. Type 2 is 1 per side. Type 3 is 2R and 2L. Type 4 is 2R and 1L. This information is fundamental for surgery.
What veins drain the blood from the bronchi and where?
Right bronchial vein drains into the Azygos vein and the Left bronchial vein drains in the Accessory Hemiazygos vein.
What are pulmonary lobule?
Primary pulmonary Lobule, which is not a used term, is the lung unit distal to a respiratory bronchiole. The secondary pulmonary tubule is the functional unit of the lung distal to a small bronchiole. It is surrounded by the Septa which contains pulmonary venules and some lymphatic vessels. The SPL contains up to a dozen acini and 30-50 PPL.
How are the pulmonary veins and arteries in structure?
Pulmonary veins: muscular structure
Pulmonary arteries: elastic structure
What is important about alveolic surface tension?
Alveoli are spherical so they are subject to surface tension. The surface tension would cause alveoli to collapse. Type II numocytes secrete surfactant against surface tension. Surfactant is made of a complex mixture of phospholipids.
What is the structure of the Sternum?
It is an unpaired bone. Lies on the midline an is composed of 3 parts. Superiorly there is the Manubrium which a pentagonal/hexagonal shape. The superior margine is characterized by a notch called Jugular notch. The superior surfaces of the manubrium make a joint with the clavicle and the lateral surface makes a joint with the first rib. The body is a flat bone which carries the chondrosternal joints of the 2 through 7 rib. The sternum ends with a protrusion called Xiphoid Process.
How many ribs do we have and what are the different kinds?
We have 12 pairs of ribs. 1-7 are called true ribs. 8-12 are false ribs and are divided in simple false ribs 8-10 and false floating ribs 11-12.
What is the structure of a true rib?
The rib undergoes a tight curvature while moving posteriorly called the Costal Angle. Moving more posteriorly the rib shows a protrusion covered in hyaline cartilage called Tubercle. There is a neck and a head of a rib. The head is characterized by two flat surfaces which form and angle. With the vertebra the rib forms an anterior costotransverse joint and 2 one superior and one inferior costovertebral joints.
Which are important ligaments for the ribs?
The superior and inferior costotransverse ligaments connects the neck of the rib with the superior and inferior transverse process.
What is the intervertebral disk?
It is a disk found in between of the vertebrae. At the center of it there is a Nucleus Pulposus which is made of loose connective tissue. The cortical part is made of several concentric layers of dense connective tissue and this part is called Annulus Fibrosus. The disk tissue is highly hypoxic so injury and arthosis caused degeneration of the tissue.
What are the different intercostal muscles and what do they do?
The external and internal intercostal muscles of the upper 4/5 ribs are elevating the ribs while the rest are probably depressing them. The innermost intercostal muscles are elevating the ribs.
What is the location of the intercostal vessels and nerves?
The intercostal vessels are inside the inferior groove that is posterior to the inferior margin of the ribs. The vein is superior, the artery is in the middle and inferior is the nerve.
What is the Pleurae, what are its different parts and why is it important?
The pleurae is like a bag that is sealed with two walls that cover the lungs. It develops separately from the lung and then it is expanded at birth. The two parts of the pleurae are the Visceral pleurae which is attached to the lung and the Parietal pleurae which is tightly attached to the inner side of the thoracic wall. The two layers of pleurae are separated by 1-3 ml of pleural liquid which avoids abrasion between them.
What are the characteristics of the Visceral pleurae?
It is characterized by two layers. One squamous mesothelioma mono layer and one of loose connective tissue/ dense connective tissue in older patients.
What is the Endothoracic fascia?
It is a layer of elastic fibers with some type I collagen. It has two layers a mesothelioma layer and a dense connective tissue layer. It is found in between the innermost intercostal muscle and the parietal pleurae.
What is a lungs peduncle or hilum?
It is the only site of exit and entrance of structures of the lungs. It is visible looking medically from the mediastinum.
What is the structure of teeth?
A tooth after eruption is composed of a part on which enamel is layered. This part is called the Crown. The clinical crown is what is above the gengiva while the anatomical crown is any part that is covered by enamel. The Root refers to anything that is not covered by enamel. The root is covered by a specialized bony structure called Cement. The internal part is formed by a layer of compact bony tissue but it is less compact than enamel and cement and it is called Dentin. Dentin is lined by a mono stratified epithelium of cuboidal to cylindrical cells called Odontoblast layer.
What is the structure of enamel?
Ameloblast cells secrete a prism of enamel shaped like a keyhole, diameter of 20 nm. Fluoride added to the enamel will make it very resistant to demineralization. The composition of enamel is 96/98% Hydroxyapatite, 2 % proteins called enamelins and some crystallization water.
What is the structure of dentin?
It is composed of odontoblast which by means of their apical surfaces send protrusions called Fibers of Tomes. Inside these protrusions there are spaces called Peridontoblast spaces into which nerve fibers extend. They also extend laterally by a number of Canaliculi. Dentin is calcified but not as much as enamel. Mainly type I collagen.
What is the Pulp chamber?
It is internal to the dentin, it contains the pulp, Mesenchymal tissue. It is highly vascularized and innervated. There is peduncle at the inferior tip of each root called Dental/Neurovascular peduncle.
What is the Periodontium?
The periodontium is anything surrounding the teeth and is fundamental for the functioning of the organ. It is composed of gengiva, periosteum, alveolar process and periodontal ligament.
What is the gengiva?
It is characterized by a multi stratified cuboidal epithelium and a lightly keratinized epithelium. The part of the gengiva that is not tightly attached to the root is called Free gengiva. Below the free gengiva there is the Attached gengiva which is connected dot the periosteum of the alveolar process. Further below we find the oral mucosa which is not keratinized anymore.
How is the surface topography of the stomach?
The Midclavicular lines split each clavicle in two parts and pass through the nipples. They are intersected by two horizontal lines. One is the Intertubercular line which is the inferior one that passes through the iliac spine L5. The superior horizontal line is the Subcostal line and it passes underneath the 10th rib, L1/L2.
How is the stomach segmented?
The stomach can be divided into three regions by means of two planes. On is horizontal and corresponds to the Cardiac notch where the esophagus makes and acute angle to enter the stomach. Above this plane everything is called the fundic region and anything below is the body of the stomach. The left margin of the stomach is called Greater curvature while the right is called Lesser curvature. The second plane is an oblique plane, the plane is located at the level of the Intermediate sulcus. This plane separates the body from the Pyloric region which ends with a constriction called Pyloric office.
What is the relationship between the stomach and the liver?
The relationship is represented by a large peritoneal fold called Lesser Omentum. it is composed on the left by a translucent ligament called Hepatogastric ligament and on the right a thicker and not translucent ligament called Hepatoduodenal ligament which contains the portal vein, biliary duct and the hepatic artery. This fold is important bc it give access to the Lesser Sac now days called the Greater Foramen. The greater curvature connects with another peritoneal fold called the Greater Omentum.
What are the different shapes of the stomach?
After a meal the stomach is quite high, reaching the 3th intercostal space called Hypertonic. Before lunch it is a bit more relaxed but still high called Orthotonic. Early morning the stomach is relaxed and low called Hypotonic. During fistic the stomach is very low bc it is empty called Atonic.
