Tag: human body

Shampoo Science: “Dirty” Hair and What Those Ingredients Actually Do

For the average person, washing their hair every day or every few days is a matter of hygienic preference rather than necessity. Unless their work or pastime brings them in contact with dirt or involves physical exertion, it is unlikely that their hair would go from being clean to truly dirty in the span of twenty-four hours.

So, what is the true science behind our “dirty” hair and the ingredients in our shampoo?

Circulatory System: Heart Structures and Functions

Circulatory System: Heart Structures and Functions; Blood flows through the heart in the following order: body –>inferior/superior vena cava –> right atrium –> tricuspid valve –> right ventricle –> pulmonary arteries –> lungs –> pulmonary veins –> left atrium –> mitral valve –> left ventricle –> aortic valve –> aorta –> body…

Seven General Functions of the Respiratory System

What is the respiratory system? In general, the respiratory system is a biological system that contains organs and structures that assist in gas exchange. Gas exchange involves the movement of carbon dioxide and oxygen between our circulating blood and air. In this educational lesson, we explore seven general functions of our respiratory system.