1. A phosphate group: This is a molecule containing phosphorus and oxygen.
2. A deoxyribose sugar: This is a five-carbon sugar.
3. A nitrogenous base: This is a molecule containing nitrogen. There are four different nitrogenous bases in DNA:
* Adenine (A)
* Thymine (T)
* Guanine (G)
* Cytosine (C)
These nucleotides are linked together in a long chain to form a DNA strand. The phosphate group of one nucleotide binds to the sugar of the next nucleotide, forming a sugar-phosphate backbone. The nitrogenous bases stick out from the backbone like rungs on a ladder.
The structure of DNA:
* Double helix: Two DNA strands twist around each other to form a double helix.
* Base pairing: The nitrogenous bases from the two strands pair up through hydrogen bonds:
* Adenine (A) always pairs with Thymine (T)
* Guanine (G) always pairs with Cytosine (C)
* Complementary strands: The two strands of DNA are complementary because the sequence of bases on one strand determines the sequence of bases on the other strand.
This unique structure of DNA allows it to store and transmit genetic information.
