Bio 150- Cardiovascular System Flashcards
Blood vessels:
arteries, arterioles, capillaries, venules, veins
Basic circuits:
Pulmonary, Systemic, Coronary, Hepatic Portal System
Components of the Cardiovascular System
- Heart=Pump blood around the body!
- Arteries & Arterioles=Carry blood AWAY from the heart (oxygenated or deoxygenated blood)
- Capillaries=Smallest blood vessels (very thin walled – why?) Connect arterioles and venules
- Venules & Veins=Carry blood back to the heart (deoxygenated or oxygenated blood)
- Blood!=Delivers nutrients and picks up wastes to/from the body’s tissues
Overall functions of the CVS
- Transport=Of gases (O2 and CO2), nutrients, waste products, processed molecules (eg., lactic acid), regulatory molecules (eg., hormones)
- Protection=Against foreign substances such as toxins or microorganisms (blood as part of the immune system)
- Maintenance/ Regulation =Of body temperature, normal pH, and osmotic composition (to maintain normal fluid and ion balance), plus restricting blood loss
Where is your heart?
-In the thoracic cavity, between the lungs, posterior to sternum
-Part of the mediastinum
Together with the trachea, esophagus, etc
(see Fig. 20-2b)
-Base: Deep to sternum + 2nd intercostal space
-Apex: Deep to the 5th intercostal space (~7-9cm to the left of the sternum)
Pericardium
A double-layered sac that surrounds the heart
Pericardial sac:
- Fibrous. Anchors heart to diaphragm, sternum, and in mediastinum
- Parietal pericardium has:
- Outer fibrous layer: Dense irregular CT
- Inner serous layer: Simple squamous epithelium plus areolar CT (thin)
Visceral pericardium
=epicardium
-Covering surface of heart
Cavity between parietal + visceral pericardium: filled with
pericardial fluid
Wall of the heart
- Epicardium (=visceral pericardium!) : Mesothelium + areolar CT
- Myocardium: thick middle layer. Cardiac muscle! *Arrangement of fibers
- Endocardium: inner layer. Thin. Simple squamous epithelium (“endothelium”) plus areolar CT
Superficial Anatomy of the Heart
-4 chambers of the heart are visible: Right and left ventricles Right and left atria (note the auricle of each!) -Grooves/ depressions: Coronary sulcus Anterior interventricular sulcus Posterior interventricular sulcus -Fat, blood vessels…
Right atrium:
Receives blood from superior and inferior venae cavae, and from the coronary sinus
Left atrium:
Receives blood from the pulmonary veins (4)
Right and left atria are separated by the
interatrial septum
Ventricles
Very thick, muscular walls!!
Blood flow:
atrium to ventricle
Right ventricle:
blood flows out via pulmonary trunk
Left ventricle:
blood flows out via aorta
R+L ventricles are separated by the
interventricular septum