Unit 7 - Unit 7: Internal Transport and Regulation of Body...

Info iconThis preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon
Unit 7: Internal Transport and Regulation of Body Fluids 1. Bacteria and Paramecium lack specialized systems for transporting nutrients and gases because they are unicellular and diffusion is sufficient. Hydra and other cnidarians have a gastrovascular cavity and because they are only two cells thick at most. Planaria and other flatworms have a flat body so a high surface area to volume ratio and also do not need specialized transport systems. 2. General features of a transport system are circulatory fluid, tubes, and a muscular pump. In an open circulatory system the blood and the hemolymph mix. An advantage of a closed circulatory system is that it is more efficient in getting blood to the body. Although insects have a high metabolic rate they are small and thus a open circulatory system is sufficient. 3. The main advantage of a double circulatory system blood is repumped after leaving the capillary beds of the lungs or skin ensuring oxygen rich blood flow to the brain and rest of the body. The heart of amphibians and reptiles is different from that of mammals because mammals have a fully divided ventricle. 4. Flow of blood in heart Right ventricle pulmonary arteries capillary beds of lungs pulmonary veins left atrium left ventricle aorta Or Coronary arties capillary beds of head/arms anterior vena cava Or capillary beds of organs/legs posterior vena cava a. During contraction of the atria the semilunar values close and the AV open. During contraction of the ventricle the semilunar open and the AV close. b. The contraction is systole and the relaxation phase is diastole c. Cardiac output is the volume of blood/min that the left ventricle pumps into the systemic circuit. Cardiac output = Heart Rate x Stroke volume d. Blood in the veins in the lower extremities are returned to the heart by contraction of smooth muscles in the walls of the veins as well as contraction of the skeletal muscle. Negative pressure breathing has an effect of venous return because the pressure change draws flood into large veins in the thoracic cavity 5. Know the following on the rat: Right and left atria: Right and left ventricles: Tricuspid valve: Bicuspid valve: Aortic and pulmonary semilunar valves: Coronary arteries: Pulmonary trunk: Coronary arteries: Subclavians: Aortic Arch: Aorta: Coeliac: Anterior mesenteric:
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Renal: Pulmonary Veins Jugulars: Right and left anterior venae cavae Posterior vena cava: 6. a. The SA node is located in the wall of the right atrium. The AV node is located between the right atrium and ventricle. The bundle branches __. And the Purkinje fibers are __ b. An electric impulse initiates at the SA node a spread via intercalated disks of the cardiac muscle cells, causing the atria to contract The AV node relays the impulse through fibers to the apex of the heart and then through the ventricular walls, causing contraction. c. Heart rate is accelerated…and slowed down…
Background image of page 2
Image of page 3
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 04/28/2008 for the course AS&RC 100 taught by Professor Blacksher,beverly during the Spring '08 term at Cornell University (Engineering School).

Page1 / 5

Unit 7 - Unit 7: Internal Transport and Regulation of Body...

This preview shows document pages 1 - 3. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online