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I
was trying to do my science homework but I could not find what I was looking
for. So I am wondering if you can put it on your site. What I
was looking for was: what are the holes called in a leaf?
Kim
Hi Kim,
From one of my botany books, here is the definition of 'stoma'.
Stoma (plural, stomata) (Gr. stoma, mouth), a minute opening, bordered
by guard cells in the epidermis of leaves and stems, through which gases
pass.
[epidermis would be the outside layer]
Hope this helps.
Dr. Pat
Dear
Dr. Pat,
I really need some help and it will be greatly appreciated. This is
for animals and plants: How many cells are there in each? What do they
each do?
Thank you very much !
Garfield
Dear Garfield,
That is a hard question to answer -- it is kind of broad.
I would
say that many cells combine to make a plant or animal. An analogy would
be if you tried to make a life-size model of the Statue of Liberty out of
meatballs. The meatballs would be the cells.
There are
trillions of cells in one human body. There are different functions for
the various kinds of cells. (All cells are pretty much the same, with
small variations between them -- but the variations are what allow the
cells to perform different tasks.) For instance you have muscle cells and
brain cells and red blood cells.
And,
plants are also composed of multi-millions or trillions of cells (depends
on the size) and they have specialized jobs -- like root cells and leaf
cells.
Thanks for
asking,
Dr. Pat
Dr.
Pat,
Are cells of the same kind, such as bone cells, different in different
animals? Why?
Your visitor, Cecilia
They
would be the same. There might be the tiniest of differences -- like
different people are basically the same, only some have blue eyes and others
brown.
Dr. Pat
Thank you
very much !
Dr.
Pat,
What does
"ER" stand for in a living cell?
Thanks, Mimi
Hi
Mimi,
Endoplasmic Reticulum
Dr. Pat
Dr.
Pat,
Your response
time is incredible. Thank you very much. But, what is
Endoplasmic Reticulum? Please explain.
Thanks, Mimi
Hi
Mimi,
The Endoplasmic Reticulum is the ruffles of membrane that extend out from
the nucleus. In places it has ribosomes attached, and there it is called
the Rough Endoplasmic Reticulum (from the days when scientists first saw
what it looked like under a microscope but did not know what it did -- so
the name is descriptive of look not function). The ER is where a lot of
changes to RNA take place and, with the ribosomes attached, where protein
synthesis takes place.
Hope this helps,
Dr. Pat
Thank
you very much. This is a great website!
Aloha (Bye in Hawaiian)
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