Question

1. We talk about how surface area plays an important role in diffusion of materials in an out of cells. Can you think of any other examples in nature or in your everyday life that increasing surface area helps the diffusion or spread of molecules?

2. What are the sensors, controllers, and effector that maintain homeostasis of your heart rate?

3. What does it mean to be healthy? Are there any health myths out there that you once thought were true?

4. Why is it important that we eat a variety of foods?

Answer 1

1. Increased surface area increases the rate of diffusion. One example is the tea.Powdering of tea increases the surface area and when hot water is poured into powdered tea leaves there is faster diffusion of chemicals that a non powdered sample.

Another example from the body systems is faster diffusion of the atmospheric gases is only possible due the presence of alveoli which greatly increases the surface area of the lungs.

2.Homeostasis of heart rate:

Change in heart rate ocuurs by stimulus where the blood pressure which are detected by the baroreceptors which act as sensors this signal is then sent ot he control center the brain where the information and is maintained by various hormones and nervous signals , these signals are sent ot the heart which is effector organ and thus the regulation or homoeostasis of the heart rate happens.

3.Health is a state complete state of the physical , emotional, mental and spiritual well being of an individual.

Some myths about health include that knuckling will give arthiritis.

4.It is crucial to include all the varieties in the diet like carbohydrates,proteins, greens etcc.. because they all constitute the key nutrients and elemnts which the body requires for proper functioning and fight diseases.