Question

NAME SID__ 31. Which of the following is a correct statement when comparing Open Circulatory Systems and Closed Circulatory Systems? a. Open Circulatory Systems generally require MORE energy to operate, since it is less efficient to circulate the entire amount of interstitial fluid in the body cavity. 8. Arthropods and Insects generally use a Closed Circulatory System, while vertebrates generally use an Open Circulatory System Both systems utilize some form of the following three components: (1) circulatory fluid, (2) vessels (.e. tubes), (3) muscle pump i.e. heart) d. Blood is circulated in Open Circulatory Systems, while Hemolymph is utilized within the Closed Circulatory Systems e. None of the above. 32. Listed below are different steps that occur during the contraction of the mammalian heart. Please select the correct sequence in which these steps for cardiac contraction occur. 1) Atria undergo contraction (systole), pumping blood through atrioventricular valves into the Ventricles that are currently relaxed (diastole). 21 Specialized cardiac muscle cells at the Sinoatrial (SA) Node, i.e. the "Pacemaker" depolarize sending Action Potentials to neighboring cells through gap junctions at electrical synapses. 31 in response to Action Potentials now originating from the heart apex, the Ventricles forcefully contract systole) in a "bottom-up" direction, while Atria relax (diastole) The Action Potentials pause in a region called the Atrioventricular (AV) node, before the electrical impulse is relayed down to the bottom of the heart via special fibers 5) Blood is pumped out of the heart through the semilunar valves. her Possible Sequence Options: 1,2,3,4,5 b. 2, 1, 4, 3,5 c. 2,1,3,4,5 @ 2,3,4, 1,5 e. 5,3,1,2,4 24315

Answer 1

Answer 31:

Circulatory system functions to transport nutrients within the body of an organism. In lower animals, such as arthropods, body interstitial fluid (hemolymph) is circulated directly within the body and such a system is called open circulatory system. It is called open because it doesn't involve any vessels. It requires more energy to function.

On the other hand, closed circulatory system involves blood vessels in which materials are transported and is found in vertebrates such as fishes, birds, human. Closed circulatory system is slightly more effective than open circulatory system.

Hence, the correct statement regarding closed and open circulatory system should be:

(a) Open circulatory system generally require MORE energy to operate since it is less efficient to circulate the entire amount of interstitial fluid in the body cavity.

Answer 32:

The general pathway of electrical conduction takes the following route in heart :

SA node > atrium > AV node > ventricles > blood pumped out of heart

(SA node stands for sino-atrial node and AV for atrio-ventricular node).

Thus, the correct choice should be:

(b) 2-1-4-3-5