Physiology Lab Final Exam 2008

Part 2

 

1. Explain what a Q10 value of 1.0 means in terms of reaction rate or metabolism.

 

Reaction is not temperature dependent

 

 

2. You are designing an experiment to measure metabolic rate. Based on the equation for cellular respiration, what are two different components that could be measured? (Hint: you measured one in lab!)

 

Oxygen consumption or carbon dioxide production

 

 

3.      How does temperature relate to biological activity?

 

An increase in temperature will cause reactions to increase until a point where enzymes are denatured.

 

4.     Explain why the term poikilothermic does not relate only to organisms

Could also pertain to cells in cell culture.

 

5.     What is a thigmiotherm?
An organism that gets energy from substratum or medium

 

6.     Why were crayfish chosen as the organism for the Q10 experiment? What is another organism that could have been used to generate similar data?

Crayfish were used because they are ectothermic, could also use snails and /or zebrafish

 

7.     An ECG consists of a series of waves, at what interval in the ECG does ventricular contraction occurs?

QT

 

8.     What is diastole?

Heart relaxation

 

9.     The leads used for ECG recording is determined by?

The placement of the recording and reference electrodes.

 

10.  What is the name of the diagram that describes the axes of the leads used for ECG recordings?

Einthovenπs triangle

 

 

11.  Draw a typical ECG wave. Label the appropriate parts.

 

 

12.  In the last lab exercise, ECG was recorded from Lead I and Lead II how was activity from the other leads determined?

using the iworx, and this is based on calculations from the lead I and II

 

13.  What is bradycardia? How is bradycardia stimulated in humans? (2 points)

a condition where by blood vessels supply non-essential organs are constricted, redirecting blood to oxygen-requiring brain and heart

 

bradycardia is stimulated by holding breath and immersing face in cold water

14.  What is the name of nerve that mediates diving response in mammals?

trigeminal

 

15.  What diving response occurs due to the stimulation of cold receptors in the nasal and pharyngeal passages?

apnea

16.  What happens to heart rate (increase or decrease) when a subjectπs face is submerged in:

(a)    cold water? (1 point) decrease

 

(b) room temperature water? (1 point) decrease

 

17.  A subject first dives into cold water, then wears a mask and snorkel and dives in cold water. Is heart rate in the absence of the mask and snorkel lower or higher than heart rate in the presence of the diving apparel?

lower

 

18.  Which two systems are working in concert in the diving reflex that normally work
in opposition?
parasympathetic and sympathetic

 

19.  What does apnea mean?
cessation of breathing

20.  Which artery is typically used to find blood pressure?
brachial

21.  There are actually 12 cardiographic leads: six limb and six chest. What is the term used to describe the six limb leads?

Coronal leads

22.  What cells (or area of the heart) is responsible for discharging electrical signals to the heart muscle in order to initiate a heart beat?

Pacemaker cells, SA node cells or SA node

23.  What does a defibrillator do?

Creates an electrical current that jump-starts a heart or re-establishes rhythm

24.  The parasympathetic nervous system influences the resting heart rate via signals from what cranial nerve?

Vagus, or tenth cranial nerve

25.  The change is heart rate that results from breathing is known as_________________________?

Respiratory sinus arrhythmia, or RSA

 

26. 
Let's say that we found the height of the QRS complex in a Lead I ECG to be 5 mm and the height of the QRS complex as 10 mm. Use the following chart to identify the value that relates to the electrical axis of the heart. (3 points).