WHAT A DOLL! 50-FOOT WOMAN TEACHES KIDS.

Byline: Phil Davis Staff Writer

Tess is a million-dollar woman with brains. A pulsating brain.

Tess, a 50-foot-long human-body simulator, is the centerpiece of the California Science Center's World of Life exhibit. She is anatomically correct in an androgynous way - a massive version of the old ``visible woman'' models. But Tess is a dazzler with strobes, chaser lights and pulsating organs to drive her point home.

Her mission: teach homeostasis, the body's remarkable, but often taken-for-granted ability to maintain a stable internal environment despite the wildly fluctuating conditions we expose it to, from soccer games to mountain climbing.

``The reality is very few science centers even talk about it,'' said David Combs, physiologist and curator of the museum's World of Life. ``What's amazing about it is probably the central tenet of physiology. People tend to think it's very complicated.''

It's not that complicated when Tess and her animated sidekick Walt explain it in a 15-minute show. Tess is stretched out in a colorful lab of gadgets. Walt provides comic relief on a screen behind her head. After laying out some body basics, Tess shows firsthand how the internal organs work together to keep a body in balance under pressure - in this case, a girl's soccer game.

Her heart thumps loudly, lungs pulsate (and almost seem real) as strobes and chaser lights illuminate the movement of blood and nerve impulses through her body. As she runs through the virtual soccer game, gauges show fuel, temperature and oxygen levels dropping. For a moment, with alarms sounding and lights flashing, it seems Tess may crash and burn. But she's only making a point.

Her body - as a human body does - makes up for the shortfall. As the heart and lungs pick up the pace, Tess moves oxygen, fuel and other essentials to the crucial systems.

``It's not like we're sitting there on a shelf percolating along; we're keeping more than 20 things constant at all times,'' Combs said. ``We go through unbelievable, extreme scenarios, and yet the whole time, basically, all these things stay constant. It's staggering.''

Children, Tess' primary audience, think she's cool, although one boy walked out when it became clear no one was going to perform surgery on her pulsating brain.

``People learn in there,'' Combs said. ``Are they physiologists when they come out? No, but they understand the basic idea, their vocabulary is increased, and their likelihood of talking about homeostasis goes way up.''

True. Dottie Krause, an English teacher from Los Angeles, admitted she had forgotten the concept of homeostasis until watching the Tess show recently. But she wondered if spending $1.7 million in grant money to teach such a basic concept was prudent.

``It's an awful lot of effort to get a point across,'' Krause said. ``This must have cost plenty. I'm wondering if it's worth it, frankly.''

Combs said Tess' hefty price tag is worth it - especially considering how may people aren't aware of such a basic biological concept.

Homeostasis is what separates higher animals from pond scum.

Pity the poor paramecium. Like a human brain cell, it needs oxygen, nutrients and a way to get rid of waste. But the paramecium lives in an environment that is subject to sudden changes in temperature, affecting the supply of food and oxygen. Meanwhile, human brain cells bask in a warm, food- and oxygen-rich environment, courtesy of the hard work of the rest of the organs.

``Essentially, they have this great environment,'' Combs said. ``That's why we evolved.''

Tess' show runs every 30 minutes. Other World of Life exhibits offer interactive activities ranging from the life of a single cell to the interaction of the human body's 100 trillion cells. It's education - buffet style.

``This is learning by free choice,'' Combs said. ``You can pick and choose what you spend time with. I hope people walk away from here with a sense of respect for the human body.''

The facts

--What: California Science Center.

--Attractions: Interactive science exhibits (including a 50-foot woman and spacewalk simulator) for all ages and a 3-D IMAX movie theater.

--Where: 700 State Drive, Los Angeles, in Exposition Park. Parking entrance is on West 39th street (39th and Figueroa streets).

--When: 10 a.m. to 5 p.m.

--Cost: Admission is free, parking costs $5, and IMAX movie prices range from $3.75 for children to $7.50 for adults.

CAPTION(S):

2 photos

Photo:

(1 -- color -- cover) Body beautiful

This 50-foot woman spills her guts in the name of science

Charlotte Schmid-Maybach/Staff Photographer

(2) Tess, the giant robot, teaches visitors about homeostasis - complete with flowing blood and pounding heart - at the California Science Center.

Charlotte Schmid-Maybach/Staff Photographer