BIO 1150 Exam 2 - Questions with Verified Answers

BIO 1150 Exam 2 - Questions with Verified Answers Is the pulmonary vein oxygenated or deoxygenated? Oxygenated Do atria have thick or thin walls? Thin Do ventricles have thick or thin walls? Thick Cardiac cycle A complete heartbeat consisting of contraction and relaxation of both atria and both ventricles Systole Contraction of the heart Diastole Relaxation of the heart Stroke volume The volume of blood pumped from a ventricle of the heart in one beat Cardiac output The volume of blood pumped into the systemic circuit per minute. Depends on heart rate and stroke volume Atrioventricular (AV) valves Separate each atrium and ventricle Semilunar valves Control blood flow to the aorta and the pulmonary artery Heart murmur Caused by back flow of blood through a defective valve What is the rate of blood flow in capillaries? Slow Do capillaries have thick or thin walls? Thin Do veins have thick or thin walls? Thin Do arteries have thick or thin walls? Thick Gas exchange supplies O2 for cellular respiration and disposes of CO2 Respiratory surfaces Need large, moist surfaces for the exchange of gases Ventilation moves the respiratory medium over the respiratory surface Countercurrent exchange blood flows in the opposite direction to water passing over the gills Tracheal system In insects, a system of branched, air-filled tubes that extends throughout the body and carries oxygen directly to cells. Lungs Unfolding in body, moist. Size and complexity correlate with an animals metabolic rate Mammalian respiratory system -branching ducts covey air to lungs -Air inhaled is filtered, warmed, humidified, and sampled for odors -Pharynx directs air to the lungs and food to the stomach Epiglottis A flap of tissue that seals off the windpipe and prevents food from entering. Alveoli -Air sacs at tips of bronchioles, surrounded by a capillary bed -lack cilia and are susceptible to contamination -surfactants cost the surface of the alveoli Negative pressure breathing A breathing system in which air is pulled into the lungs when the lung volume is expanded. Tidal volume Amount of air that moves in and out of the lungs during a normal breath Vital capacity The total volume of air that can be exhaled after maximal inhalation. Residual volume Air that remains in the lungs after exhalation