Seiberlich is a physical therapist at Children's Clinics for Rehabilitative Services in Tucson , Ariz. She and her partner, Kimberly Becerril, an occupational therapist, are discussing how to choose and properly fit a wheelchair.

"For instance," Becerril says, "one of most fundamental issues in choosing a chair is transportation. How will chair be moved from home to school? If answer is in back of a station wagon, then a power chair is out. Even with a van, a power chair is going to need a ramp, because it's too heavy to lift in. A lot of our kids would benefit from a power chair, but unless transportation issue can be solved, it won't be right choice."

Becerril knows a number of children who have power chairs who leave them at school, and use a manual chair at home.

"During process of choosing a chair, we do a lot of transfer analysis," Seiberlich says. "We want to know who's going to be doing them (transfers), and we want parents to demonstrate how they're doing them. We can suggest ways to make it easier, such as use of a transfer board, or a Hoyer lift in appropriate situations.

"Most parents who've never seen a board are surprised by what a difference they can make," she adds. "Still, if they are lifting child and chair several times a day, they are at a big risk for developing back problems. We had one mother with bruises all over her legs from constantly lifting chair. Choosing a lighter chair, and one with some removable hardware, can make a big difference."

Seiberlich and Becerril note that they can't make all decisions regarding choice of a chair, either.

"We want involvement of those people who see child on a regular basis," Becerril says.

"That means parents, of course, because they know child best. But we also want school involved, especially teacher or therapist who sees child daily functioning outside home. The issues at school can be quite different from those at home."

Becerril says that they also want chair supplier involved, to tell them what's available. "We'll describe need, and supplier can describe what they have to meet it. We can make mistakes if we do it ourselves, but if we have whole team, we can cover all bases."

Lifestyle and Environment What's right style of chair? While this will depend on individual needs and preferences, Becerril offers some important guidelines.

"Lots of kids want sports frame look: It's got a low profile and looks great. However, these frames are rigid: they can't be folded, and they can't grow with child. So we wouldn't recommend one of these at least until they are finished growing. Even then, transportation issue remains a problem."

Seiberlich adds, "We also would never recommend a chair without removable armrests or footrests. One of our clients who got a chair with rigid footrests went from independent transfers to requiring two people to move him. Luckily, we were able to recycle chair to someone for whom it made more sense."

When it's time to choose individual components, Seiberlich and Becerril want to hear about lifestyle, terrain and environment.

"We can choose wheels based on how rough ground is around home," Seiberlich says. "Here in desert, we recommend airless inserts. One good cactus spine and you've got a flat! Back East, we've got to consider mud, snow and rain."

"We also want to know about inside of home: Will an otherwise ideal chair have trouble getting through narrow doorways? If so, and there's no money to redo home, we've got to change our thinking," Becerril says.

Social and educational factors come into play here as well. "Is chair appropriate for school setting?" Seiberlich says. "For instance, does height of chair put child above or below classmates? Can we make small changes to get it looking more streamlined, if that's what child wants? If we can think of these things up front, it can save a lot of time and expense later on."

Growing With Child Both X-shaped cross brace (black) and front frame sections (blue) can be replaced as a child grows.

And expense is a huge issue: A manual wheelchair with custom seating can cost $5,000, while a power chair might be four times that. A really good cushion alone might be $300 or $400. Becerril notes that most of this is covered by insurance for many families. "And if you buy right kind of chair, one that can grow with child, that investment can last 10 or 12 years. This is child's mobility, and his independence. It's important to get it right."

What does it mean for a chair to grow with child? The idea may be new to those who think of clunky "one-size-fits-all" sling back chairs as only type there is. Most chairs today can be widened by changing cross brace supports underneath, and lengthened by replacing front frame sections that hold leg supports.

First, we need to have an understanding of just exactly what enzymes are and what they do for us.

Enzymes are proteins made by cells in our bodies and by all living organisms. They are specialized proteins that do work, such as synthesizing chemicals, rearranging molecules, adding elements to compounds, and breaking down compounds. Enzymes are protein catalysts. They cause biological reactions to occur under conditions that sustain life. Many types of enzymes exist and each type does one specific function. For an enzyme to work, material it works upon must be present. If no such material is available to enzyme, enzyme performs no function. There are also metabolic enzymes in our body, but this discussion is limited to digestive enzymes that help break down food.

We see in this description of enzymes that they break down compounds. In our gut – stomach and intestines – they help to break down food into basic nutritional bits our bodies can use for nourishment. Without this enzymic activity our bodies could not extract nutrition from food and we would wither and die. Let’s see exactly how enzymes work.