This week in lab, students begin looking at reproductive physiology before turning to the anatomy of the brain. In order to prepare for the full reproduction lab, the teaching assistants castrate a male rat in order to study the effects of testosterone deprivation after two weeks. Students observe this procedure before proceeding on to neuroanatomy.
The focus of this week's lab is how humans digest carbohydrates, proteins and lipids (fats). In lab, each group places a small amount of each macronutrient into different test tubes, simulating different situations in the body.
This week in lab, students measure their metabolic rate using indirect calorimetry. This method is used in lab because it is simpler to measure oxygen consumption versus heat production in the lab setting. Using a respirometer, the teaching assistant fills the tank with 100% oxygen, which the students breathe over a period of 4 to 5 minutes. The decrease in tank volume represents that student's oxygen consumption. From there, students can calculate their resting metabolic rate.
This week's lab turns to a study of muscle anatomy and physiology by using a frog's gastrocnemius muscle and sciatic nerve. Once dissected out, the teaching assistants help students correctly set up the experiment.
Using the same equipment set-up from the previous week, this lab's focus is on the anatomy and physiology of the heart. Again using a frog, students carefully hook up the apex of the frog's heart to the force transducer to obtain a recording of the frog's normal heartbeat. One of the objectives of this lab is to identify differences between skeletal muscle students saw last week and cardiac muscle. To observe these differences, students observe the refractory period, effect of stretch on contraction strength and attempt to obtain tetanus.
During this lab, students look at the entire cardiovascular system while they learn about heart sounds, how to measure blood pressure and record and explain the physiology of a peripheral pulse wave and electrocardiogram (ECG). Students also learn about Einthoven's Triangle and how to determine the heart's physical location from electrical potential differences across the heart.
In the last lab we turn our attention to physical fitness. Each group member performs various physical activities to determine how physically fit they are and perform pulmonary functions tests to determine respiratory fitness.
In this week's lab students examine respiratory function as well as all of the components of blood. A member from each group will wear a respiratory belt that records normal breathing and then perform various tasks so everyone can observe the effects on the respiratory rate and depth. Students will also obtain graphs that allow them to measure different lung volumes as well as the elasticity of their lungs.