BIOL 129 Study Guide - Midterm Guide: Ductus Venosus, Renal Fascia, Peritoneum
BIOL 129 // EXAM 3
1. heart → the “pump of cardiovascular system,” ⅔ of it lies left of the median line.
a. located in the thoracic cavity in an area called the mediastinum
i. posterior to ribcage, sternum
ii. superior to diaphragm
iii. anterior to trachea
iv. between the lungs
b. great veins + arteries sit at the base, the pointed tip is the apex
c. parietal pericardium → outermost covering.
i. consists of fibrous + serous layers
d. visceral pericardium/epicardium → serous layer folds back over the heart to form
this
e. pericardial cavity → between the epicardium and the parietal pericardium, filled
with pericardial fluid that lubricates and cushions the heart
f. heart wall → thick, consists of 3 layers
i. 3 layers
1. epicardium → visceral pericardium
2. myocardium → muscle tissue
3. endocardium → covers all inner surfaces of the heart, including
heart valves
g. atria → superior chambers of the heart
i. receive blood from organs
ii. pump with low pressure → no inlet valves, thin walls
h. ventricles → left is way thicker due to pumping oxygenated blood + pumps blood
to entire body
i. hypertrophy v. hyperplasia → both increase tissue mass
1. hyperplasia → normal cell division
2. hypertrophy → preexisting cells swell
a. athletic v. pathological → good in athletes, bad
pathologically (genetic, valve diseases, heart disease,
hypertension)
i. valves → 2 types of valve activity
i. systole → ventricular contraction, ventricles empty
1. chordae tendinae → keeps valve shut due to papillary muscle
pulling on it. papillary muscle injury causes heart murmurs
ii. diastole → ventricular relaxation, ventricles fill with blood
iii. valve prolapse → very common on the left side
1. results in mitral regurgitation → pooling back of blood into atrium,
heart murmur
2. symptoms → heart palpitations, atrial fibrillation, syncope
a. syncope → fainting spells
j. circuits + blood flow
i. pulmonary circuit → blood to lungs only, sole purpose of oxygenation
ii. systemic circuit → blood to rest of body, sole purpose of deoxygenation
