Plant & Soil Sciences eLibraryPRO
control panel control panel

DNA and DNA Extraction

Rate Me


Nucleotides make up DNA. DNA makes up genes, and genes are small segments of chromosomes.

Picture by Metin Tuna
Chromosomes from brome grass (Bromus inermis). Photograph taken through a light microscope at 1000X magnification.
DNA is packaged in the cell into structures called chromosomes.

Chromosomes are the form by which genetic information is passed from old cells to new cells, one generation to the next, resulting in the successful and reliable inheritance of traits.

Every cell in an organism contains two copies of every chromosome present in that organism. For example, humans have 46 chromosomes in their body, 23 were inherited from the father and 23 from the mother. Gametes, the reproductive cells of an organism, (egg or sperm), have only one set of chromosomes. When the two gametes unite, they form a living embryo with two sets of genetic information. Therefore, we actually have two copies of the genetic information for each trait. Sometimes one copy controls trait expression, and other times both copies influence a trait. As a result, the offspring will have characteristics of both the mother and the father.


Be the first to write a comment...

Control Panel cancel

Create activities for your moodle courses. Moodle Go to moodle
Select and group e-Library Lessons to create your own package... My Communities
Community Blogs Community Media

My Joined Communities

My Blogs - a journal of my thoughts... My Blogs
My Comments - my thoughts expressed as a feedback... My Comments
Classes that I am taking Registered Classes
Class Blogs Class Media
Check the scores of assesments that you have taken Taken Assessments
Please confirm your selection.