The Effects Of Temperature On Heart Rate And Strength Of Contraction

2152 Words9 Pages
Question: What are the effects of temperature on heart rate and strength of contraction? The effects of temperature can either increase the heart rate or decrease the heart rate. The temperature can also effect the strength of contraction either by making the contraction stronger or weaker. Background: Explain on the cellular level how dropping warm Ringers solution on the frog’s heart would affect the cells of the SA node. Dropping warm Ringers solution on the frog’s heart would increase the heart rate because the calcium channels open faster. Explain on the cellular level how dropping warm Ringers solution on the frog’s heart would affect the cells of the contractile muscle of the ventricles. Dropping warm Ringers solution on the frog’s heart would increase the heart rate because the actin binds to the myosin more quickly due to the calcium channels opening faster leading to faster contraction of the heart. Hypotheses: Do you expect heat to be a chronotropic factor? Yes Do you expect heat to be an inotropic factor? Yes Procedure and Results: Control Heart Rate (After rinsing) beats/min Experimental procedure Heart Rate after treatment beats/min Change in Heart Rate beats/min Strength of Contraction after treatment compared to normal (stronger or weaker) Baseline rate: 72 Continuously drop warm Frog Ringer’s onto the heart 48 -24 Weaker Rate after rinsing: 72 Continuously drop cold Frog Ringer’s onto the heart 60 -12 Weaker Increasing temperature decreases heart rate.

More about The Effects Of Temperature On Heart Rate And Strength Of Contraction

Open Document