Franklin Lew - Profile
The skeleton
The skeletal system has many important functions. The skeleton supports the body, protects internal organs, provides for movement, stores mineral reserves.... 
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Drugs and the nervous system
By definition, a drug is any substance, other than food, that changes the structure or function of the body.. Read
Nervous system
Play any team sport—basketball, softball, soccer—and you will discover that communication is one of the keys to success.. Read
Somatic nervous system
The somatic nervous system regulates activities that are under conscious control, such as the movement of the skeletal muscles.. Read
Divisions of the nervous system
Neurons do not act alone. Instead, they are joined together to form a complex network—the nervous system.. Read
Nerve impulse
The production of a nerve impulse can be compared to the flow of electricity through a wire.. Read
Skeletal system
To retain their shape, all organisms need some type of support. Thickened cell membranes provide the support for single- celled organisms.. Read
Central nervous system
The central nervous system consists of the brain, and the spinal cord.. Read
Peripheral nervous system
The peripheral nervous system lies outside of the central nervous system. It consists of all of the nerves and associated cells that are not part of the brain and the spinal cord.. Read
The autonomic nervous system
The autonomic nervous system regulates activities that are automatic, or involuntary.. Read
Senses of the body
The body contains millions of neurons that react directly to stimuli from the environment, including light, sound, motion, chemicals, pressure, or changes in temperature.. Read
Sense of vision in humans
The world around us is bathed in light. The sense organs that we use to sense light are the eyes.. Read
Hearing and balance
The human ear has two sensory functions. One of these functions is hearing. The other function is maintaining balance.. Read
Smell and taste senses
You may never have thought of it this way, but your sense of smell is actually an ability to detect chemicals.. Read
Structure of bones
It is easy to think of bones as nonliving. After all, most of the mass of bone is mineral salts— mainly calcium and phosphorus.. Read
Development of bones
The skeleton of a newborn baby is composed almost entirely of a type of connective tissue called cartilage.. Read
Types of joints
A place where one bone attaches to another bone is called a joint. Joints permit bones to move without damaging each other. Some joints.... Read
Structure of joints
In freely movable joints, the ends of the bones are covered with a smooth surface layer of cartilage that protects the bones as they move against each other.. Read
Circulation in chordates
Like modern tunicates and lancelets, the first chordates probably had simple circulatory systems. Tunicates, for example, have short, tubelike hearts with a simple pump.. Read
Using remote sensing to study animal behavior
Studying any animal in the wild is difficult. But following elephants as they travel through a jungle or blue whales as they swim through the open ocean is almost impossible.. Read
