response 75 of 100:

Feb 8 19:33 UTC 1998

I'm assuming there's more to it than just the heart wearing out sooner the
more it does.  Or is it just the regular excersize, which makes the heart work
harder some of the time, does enough to ease the workload on the heart at
other times?

response 77 of 100:

Feb 8 23:34 UTC 1998

There is some guy out there right now selling a book that
reports every heart is programmed, from birth, for just so many
beats.  So if you use them all up carrying around 100 extra
pounds, hey, your choice. ;-)

Experts tend to see obesity and heart disease from different
perspectives.  Obese people have a higher rate of heart 
disease and death from sudden heart attack than the general
population, but why is disputed.  Some say it is the extra
work expected of the heart to perfuse all that extra tissue.
Others say it is mostly due to the inactive lifestyle of
most obese people.  Some say it is the same genetics that
make you prone to obesity that bundles with it cardiomyopathy
and high cholesterol levels.  About the only thing everyone
agrees with is that you have better odds of living longer
if you're not morbidly obese.

response 79 of 100:

Feb 9 04:04 UTC 1998

The problem, really, is that there's some correlation between exercise and
skinniness, so the two are hard to separate as to their benefits.

response 81 of 100:

Feb 12 00:27 UTC 1998

Color vision is sex-linked.  The gene for seeing red is on the X chromosome,
so men have only one copy.  If it is bad, they can't see any difference
between red and green.  But even more interesting, there are two slightly
different variants of the gene for red vision, so that some women have red
receptors for two slightly different wavelengths.  That lets some women see
more colors than men or other women.  I have heard that women tend to
distinguish between a lot more colors than men, and to use much more explicit
color names, and care more about the colors they wear.  One theory is that
it was more important for women to be able to spot colored fruit, while the
men were out hunting for brown or grey animals.  Fruit is often red, because
that is the color best seen by birds.  (If you don't want the birds to eat
your cherries, grow yellow ones.)
Insects, on the other hand, see yellow, violet, or ultraviolet, and can see
patterns in white flowers that humans cannot.  There is often a pattern
directing them to the center.  

response 83 of 100:

Feb 12 19:30 UTC 1998

But picking green ones (except for gooseberries) means they are unripe.  For
some reason, birds can tolerate berries that people cannot.  These berries
all exist to be eaten by something and therefore distribute the seeds.
        Regarding the X and Y chromosomes, there are other sex-linked diseases,
such as hemophilia, due to one bad copy of the X chromosome (women have two
X's so are less likely not to have at least one good one). 
Glucose-6-phosphate dehydrogenase (G6PD) is an X-linked gene, and if you have
no good copies of it you can develop anemia due to enzyme deficiency after
eating fava beans, or coming in contact with mothballs or sulfa antibiotics.
The colorblind problem can be due to the loss of either the red or the green
gene, and in W. Europea about 5 percent of males cannot see green properly
and 1 percent cannot see red.  There is a possible Y-linked trait, passed from
father to son, called hairy pinna (hair all over the ear, but not enough to
make you look like a werewolf.)  The advantage of having a Y chromosome, even
though it is lacking a lot of useful genes, is that it makes the sperm
fractionally lighter so that it can win more races.  Therefore more males are
conceived, to make up for more dying before birth or shortly after.  At birth
there are about 6% more males.  A selfish gene?

response 85 of 100:

Feb 14 01:13 UTC 1998

I have never heard about anyone seeing less yellow, how interesting.  Are
there any particular circumstances, such as different kinds of artificial
light, under which you see yellow more poorly.  Maybe you have just a small
amount of the color receptor for yellow because you only have one functional
gene for it?  I wonder if there are any men who don't see yellow at all.

response 87 of 100:

Feb 14 13:47 UTC 1998

I guess that I have pretty good color vision.  Once, though, I got tested for
colorblindness because I was having trouble connecting names to colors
accurately.  I have a poor connection between language and sense sections of
my brain...

response 89 of 100:

Feb 15 13:35 UTC 1998

No, it's not really a common pattern among any one type of person (although
you could argue that it creates certain types...).  I have a very good grasp
of language, and a great set of ears (hearing plus mental processing), but
often the connection is poor.  I might remember a conversation I have with
somebody, but not their name, or even temporarily forget the name of somebody
I already know.  I can pick up sounds in a language, and also understand the
ltructure, but as for connecting the two... :(

response 91 of 100:

Feb 15 19:34 UTC 1998

re 89, there are people with no connection between their brain hemispheres
who can see or feel an object, describe what to do with it, draw it, etc.,
but not name it if the sensory input is going into the left hand or eye, which
feeds it to the right brain hemisphere, because the left hemisphere (at leasst
in most people, maybe not dyslexics) is responsible for language.  Usually
htere is crossover.  Maybe you have weaker crossover?
        Re 90, sounds like you are lacking some or all of the cones, or sensory
cells, for yellow-green, meaning you are one of those rare colorblind XXs!
There are supposed to be only 0.4% of women and about 8% of men who are
colorblind in any way.  Do you have male relatives who can't see yellow, or
tell aqua from blue?  In particular your father or a brother?  My theory is
that the light which is usually absorved by the cones for green, is not
absorbed and there is therefore too much of it for the other color cones. 
No I have not heard of light making anyone sleepy.  I have heard of Seasonal
Affective Disorder, where the lack of light in the winter makes some people
sleepy because they need light to stimulate hormone production.  I have not
read up on night vision, maybe you need to eat more carrots?  Or maybe you
also have a deficit of rods (that see in low light but only in grey).  Once
you get accustomed to the dark, do you know if you can see better in it that
other people?  It would be an interesting test.

response 93 of 100:

Feb 16 04:47 UTC 1998

A housemate of mine who I am sure had SAD was always complaining that there
was not enough light at work, and even got a note from the doctor that told
his employers they had to given him a desk near a window.  He thought it had
something to do with his extreme shortsightedness, that he needed to rest his
eyes on distant objects frequently.  His symptoms were wanting to die and
refusing to get out of bed from about November until the sun started shining
againg in Jan or Feb, then hardly sleeping at all until about June.  ANother
symptom was needing the shades up and two hours of sunlight to wake up.  He
tried medication, and finally moved to sunny California.  Supposedly light
treatments with a very bright specially constructed light, for about half hour
in the morning, will fix the light-related hormone problem.  Theere was a good
book in the library that I got out for the roommate, who always felt better
when he could manage to drag himself out to the sunporch to read about the
problem (the light helped).
        I have found that as I get older the glare at night bothers me.

response 95 of 100:

Feb 16 19:46 UTC 1998

That article on colorblindness that I mentioned said some people cannot see
certain wavelengths (shades) of some colors.  Have you ever tried looking at
all the computer-available colors to see which ones matched?

response 97 of 100:

Feb 17 00:01 UTC 1998

If someone eats a well-balanced diet, and is not a couch potato, I expect they
will end up at the proper weight for them, which is not necessarily the same
for all of us.  Exceptions would be people with metabolic disorders.
        Re colorblindness, please see coop item #34, proposing a new genetics
conference.  We could talk about genetics and diet, for instance some people
need more of a certain vitamin, or come from an ancestry where periodic
famines were more common, and it was therefore highly advantageous to be able
to store fat.
        Dieting in itself is extremely stressful, making the body think there
is a famine.  If you want to modify your weight, modify the type of food you
eat, and the balance of different nutrients, not just the calorie or fat
count.  You will end up a lot healthier at any weight.  (This has gotten
pretty far afield from the topic, sorry).