Anatomy Fall 2009--Rozema
Unit 3: Circulatory System
Structure & Function
*Notes were given orally in conjunction with Respiratory System Diagram & Cardiovascular System Diagram.
Function:
-Circulate nutrients to muscle tissue (cells in need).
-Nutrients = Oxygen, Sugars, Salts/Electrolytes
-Circulate wastes away from muscle tissue (cells expelling).
-Wastes = Carbon Dioxide, Acids/Bases, Cell Parts/Foreign Substances
Big Structures:
-Respiratory System = nose/mouth, pharynx, larynx, trachea, bronchi, lungs, alveoli
-Cardiovascular System = blood, blood cells, heart, veins + arteries
-Lymphatic System = lymph vessels + nodes, white blood cells
Respiratory System:
-Nasal Passage & Nose: Take in oxygen and expel carbon dioxide. Respiratory system’s connection to the outside environment. While both provide means for taking in air from the outside, air is most properly meant to enter through the nasal cavity. The nasal cavity contains a mucus lining and tiny cilia, both which help to catch foreign substances and cells trapped in the inhaled air. Air taken in through the mouth is unfiltered, and often contains non-useful/harmful agents.
-Pharynx: Passageway directly connected to the nasal and oral passageways. Often called the “throat”.
-Larynx: (Also called the “voice box”) Sits beneath the pharynx. The larynx is protected by a flap of elastic cartilage called the epiglottis, meant to prevent food from entering into the respiratory system. When non-air products enter the larynx (and move past the epiglottis) it triggers a cough-reflex as means to expel the foreign product out of the larynx. Folds of tissue in the larynx form the vocal cords/folds, which vibrate when air is expelled through them. Changes in the frequency of the vibrations results in different tonation.
-Trachea: (Also called the “windpipe”). The trachea is lined with mucus and cilia which beat against the flow of incoming air. The goal is to trap any foreign particles, and force them back into the throat. This tactic is also used to propel excess lung-fluid out into the throat (smoking kills cilia). The trachea is made of harder, hyaline cartilage, which maintains the open shape of the trachea, regardless of respiratory pressures. Trachea directly connects air to the lungs.
-Bronchial Tube: Seen as the branches coming off of the trachea, and directly dives into the lungs.
-Lungs: Main organs of the thoracic cavity.
-Bronchioles: tiny subdivisions of the bronchial tubes, filling lung tissue, and directly connected to the alveoli.
-Alveoli: tiny air sacs which are covered in capillaries from the lung tissue, and directly exchange gases between the lungs and blood.
-Pleura: The type of membrane which covers the lungs, and secretes a pleural fluid, which allows the lungs to easily move along the inside of the thoracic cavity during breathing. Though the entire lung set can move against the thoracic cavity, the pleural membrane keeps the lungs together and within the cavity.
-*Pleurisy: Condition in which the pleura either decrease fluid secretion, or overproduce fluid secretion. If pleural fluid is decreased, the lungs literally rub against the insides of the ribs causing great pain. If pleural fluid is increased, pressure in the lungs increases, and can hinder the ability to
-Diaphragm: muscle directly underneath the lungs, which changes internal pressure of the thoracic cavity by contracting and relaxing.
Cardiovascular System:
-Superior Vena Cava: Giant Pulmonary trunk/artery going into the right side of the heart (at the top). Carries oxygen-depleted blood into the heart.
-Inferior Vena Cava: Giant Pulmonary trunk/artery going into the right side of the heart (at the bottom). Carries oxygen-depleted blood into the heart.
-Right Atrium: Top, Right side of the heart. Fills with oxygen-depleted blood.
-Tricuspid Valve: The valve which separates the right atrium and ventricle. The valve remains open during ventricular filling, and closes during ventricular contraction and expelling.
-Right Ventricle: Bottom, right side of the heart. Fills with oxygen-depleted blood from the right atrium. Contracts to expel oxygen-depleted blood out of the Left Pulmonary Artery.
-Pulmonary Semilunar Valve: The valve which separates the right ventricle from the left pulmonary artery. The valve remains closed during ventricular filling, and opens during ventricular contraction.
-Septum: the cardiac muscle which separates the right from the left side of the heart.
-Left Pulmonary Artery: The large artery by which oxygen depleted blood is pumped out of (from the right ventricle), and sent to the lungs.
-Left Pulmonary Veins: The veins by which oxygen-rich blood enters the left atrium (from the lungs).
-Left Atrium: Top, Left side of the heart. Fills with oxygen-rich blood.
-Bicuspid Valve: The valve which separates the left atrium from the the left ventricle. The valve remains open during ventricular filling, and closes during ventricular contraction.
-Left Ventricle: Bottom, left side of the heart. Fills with oxygen-rich blood from the left atrium.
-Aortic Semilunar Valve: The valve which separates the left ventricle from the aorta/aortic arch. The valve remains closed during ventricular filling, and opens during ventricular contraction.
-Aorta: The large arch of arteries at the top of the heart. Used to expel oxygen-rich blood to tissues in need (the rest of the body).
-Arteries = Oxygen=rich blood to tissues, Veins = Oxygen-poor blood to lungs.