Search found 37 matches

by Edher
Sat May 13, 2006 3:37 pm
Forum: General Discussion
Topic: Gene Knockout
Replies: 0
Views: 1082

Gene Knockout

Saludos, Would someone be so kind to please enlighten me in the realm of "gene knockout"? As of today, I only have a vague notion of the purpose of this method and only a general hint of how the process is executed. If you could redirect me to a page with diagrams and much more helpful inf...
by Edher
Mon Feb 20, 2006 12:24 am
Forum: General Discussion
Topic: Herman Hesse and biology
Replies: 0
Views: 1678

Herman Hesse and biology

Saludos, I hope you don't consider this to be offtopic but as I was reading "Demian" by Hermann Hesse, he presents an analogy using the characteristics of a certain butterfly. In my opinion, I think his example is invalid, but I would like to read your comments. "You see, we don't hav...
by Edher
Tue Dec 27, 2005 8:31 pm
Forum: Physiology
Topic: Hair and DNA
Replies: 31
Views: 82157

Hair and DNA

Saludos, Is it really possible to use hair for things such as paternity tests, identification of the culprit a crime scence, etc? As far as I'm concerned hair is composed of proteins not cells, how can they extract DNA from it? Is it perhaps from the part that was connected to the hair follicle? Tha...
by Edher
Mon Nov 14, 2005 3:52 am
Forum: Human Biology
Topic: Blood Pressure
Replies: 7
Views: 9065

Blood Pressure

Saludos,

I'm trying to understand how blood pressure is measured. Why is there two readings? The first one I get, but what does the second one tells us?

Thank You,
Edher
by Edher
Sun Nov 13, 2005 10:59 pm
Forum: Physiology
Topic: Veins and Arteries Vs. Capillaries
Replies: 11
Views: 19829

Veins and Arteries Vs. Capillaries

Saludos,

I have a small curious doubt. How porous are veins and arteries?

In other words, do veins and arteries exchange a lot of chemicals before their arrival to capillary beds, or does the exchange all take place in the capillaries?

Thank You,
Edher
by Edher
Thu Sep 01, 2005 1:59 am
Forum: Botany Discussion
Topic: Tissue and Tissue System
Replies: 1
Views: 3233

Tissue and Tissue System

Saludos,

I'm currently reading about the anatomy of plants and they talk about tissues and tissue systems. What exactly is the difference between the two. And why is a tissue system not an organ?

Thousand Thanks,
Edher
by Edher
Thu Sep 01, 2005 1:51 am
Forum: Botany Discussion
Topic: Branch or Leave
Replies: 1
Views: 4340

Branch or Leave

Saludos,

As I was reading about simple leaves, compound leafs, and doubly compound leafs, I became puzzled as to how to determine what's a leaf and what's a lateral shoot (branch.)

More in detail, how can you tell the difference between a petiole and branch?

Thousand Thanks,
Edher
by Edher
Sun Aug 28, 2005 6:41 pm
Forum: Botany Discussion
Topic: Cell Nuclei in Ovule
Replies: 1
Views: 3910

Cell Nuclei in Ovule

Saludos, I'm currently studying about the reproductive cycle of angiosperms. I have a question about the female gametophyte. There is a point where it's made up of: - Antipodal Cells - Pollar Cells - Synergids - Egg The polar nuclei, are they actually nuclei floating around the ovule? And if they ar...
by Edher
Sun Aug 28, 2005 6:34 pm
Forum: Botany Discussion
Topic: Pollen Grain, Tube Cells, Style Girth
Replies: 4
Views: 6691

Pollen Grain, Tube Cells, Style Girth

Saludos, At this moment, I'm studying the reproductive cycle of angiosperms. My question is, when pollen grains are transferred from anthers of stamen to the stigma of carpel, how many pollen grains actually enter the carpel? What happens when one pollen grain has already developed its respective tu...
by Edher
Wed Mar 30, 2005 5:34 am
Forum: Human Biology
Topic: Largest Organ
Replies: 1
Views: 3739

Largest Organ

Saludos,

Does anyone know the average size of human skin in meters square?

Thank You,
Edher
by Edher
Mon Mar 28, 2005 2:53 am
Forum: Genetics
Topic: Crossing Over
Replies: 12
Views: 32469

You're right, I forgot about Meiosis I. Let me correct it.

Edher
by Edher
Sun Mar 27, 2005 10:18 pm
Forum: Genetics
Topic: Crossing Over
Replies: 12
Views: 32469

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