Internet:  DNA, Genes, and Heredity


Click on the “Tour of the Basics” and watch the following:  “What is DNA?”, What is a Gene?”, and “ What is a Chromosome?”   Define the following terms.


A)        DNA


DNA stands for DeoxyriboNucleic Acid and is found in the nucleus of almost every cell in your body.  The DNA molecule is in the form of a double helix.  The DNA alphabet consists of four letters: guanine, adenine, thymine, and cytosine.  Adenine always pairs with thymine and cytosine always pairs with guanine.  Your 46 chromosomes contain about 35,000 genes which are made of DNA strands. 


B)        Genes


DNA strands are composed to make genes.  They are the instructions manuals for our bodies.  Genes are the directions for building all the proteins that make our bodies function.


C)        Chromosome


Chromosomes contain genes which are made of DNA.  Each human cell has 46 chromosomes.  Half the chromosomes come from the mother while the other half come from the father.


How many Chromosomes?


1)         Carp

  104 chromosomes 

2)         Mosquito

  6 chromosomes

3)         Onion

 16 chromosomes          

Finish the “Tour of the Basics” by watching:  “What is a Protein”, “What is Heredity”, and “What is a Trait.”  (Use the back of the page if necessary.)


Notes on “What is a Protein”


Notes will vary



Notes on “What is Heredity”


Notes will vary



Notes on “What is a Trait”


Notes will vary



 Click here F to return to Genetics Activity.