The skeletal system
By: Jeannette Payne
The normal human skeleton has 206 bones. Each of them are classified according to their shape and size, and each having their own purpose. The skeletal system as a whole has several of its own responsibilities. Probably the most obvious of these, is its...
Reasons why oxygen is so important to the blood and cells
By: Allen Teal
Oxygen enters our body as a gas with two oxygen atoms attached to each other to make one molecule of oxygen. It exits the body as either two oxygen attached to a carbon atom as carbon dioxide or as one oxygen atom bonded to...
Structure and function of the ovaries
By: Lisa Stephens
The ovaries are a pair of ovum-producing glands that are part of the female reproductive system. Each ovary is oval shaped and roughly the size of an almond. They sit just above the fallopian tubes in the lateral wall of the pelvis in an area...
Why do humans need pain?
By: Matt Bird
Scenario one: You get up in the morning. You crawl out of bed, stub your foot on the door on your way out, bang your elbow on a wall, fall down the stairs and, as you're getting up, accidentally nick your finger on a sharp...
Hormone production in the human body
By: Tarek Musslimani
Hormones are chemical compounds inside our body that regulate the function of the various organs in our body. Most Hormone secretions from the endocrine glands are regulated by negative feedback loops except most Hormones that are secreted by the pituitary gland. These hormones are...
A look at how varicose veins develop
By: Lokemun Magar
Have you ever wondered how varicose veins develop? What causes those veins to bulge into those ugly and swollen pipes which snake above the surface of the skin? Why are they pipes of ugly worms usually found on the calves and thighs where everyone else...
Basic terminology of the human heart
By: Alicia M Prater PhD
The human heart is a specialized organ in the chest cavity that pumps blood to the tissues. It also receives blood from the tissues to recycle carbon dioxide and oxygen via the lungs. Here is some basic terminology that is used when discussing the human...
Explaining blood formation in the human body
By: Wendy R.
Blood formation in the human body is truly a remarkable process. Blood cells do not form in the bloodstream itself, but in certain areas of the body where bone marrow is present. Where bone marrow is and blood formation takes place depends on whether you...
Structure and function of the thyroid
By: Tarek Musslimani
The thyroid gland is an endocrine gland that is located on the top of the respiratory tract, anterior to the trachea. The thyroid is composed of follicles that secrete three types of hormones. Two main types of cells exist in each follicle. These are first...
Structure and function of the human brain
By: Tarek Musslimani
The human brain is composed of the two hemispheres and the brain stem and the cerebellum. Each hemisphere is connected to the other hemisphere by a membrane that is called the corpus callosum. The functional cells of the brain are called neurons. These are...

 

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