THE DNA
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THE DNA
DNA, a molecule found in the cell’s nucleus containing information about protein synthesis. It also transmits information related to genetic inheritance. The research of George Mendel. Structure and localisation. Functions of DNA. RNA. Human genetics. Mutation and evolution. Summary.
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INTRODUCTION
- The DNA or the Deoxyribonucleic Acid is responsible for the tremendous variety of living-beings. It contains information about protein synthesis and is the transmitter of all the genetic inheritance.
HISTORY
- Gregor Mendel was the first man to examine the way in which biological characteristics are inherited.
- The physical features are transmitted separately in minute, physical units called genes.
- Nowadays, we know that chromosomes are made up of almost two metres of rolled-up DNA molecules.
STRUCTURE AND LOCALIZATION
- Chromosomes are made up of chains of DNA
- Composition and structure of the DNA.
FUNCTION OF DNA
- All living-beings function using the same basic mechanisms.
- The cells
- DNA information
- RNA. Ribosomes.
- Proteins. Enzymes.
HUMAN GENETICS
- In human reproduction, each individual cell receives a complete group of 46 chromosomes. 23 from the female ovum and 23 from the male spermatozoon.
- These chromosomes are XX in women and XY in men
MUTATION AND EVOLUTION
- Occasionally, individuals belonging to the same species present different characteristics due to their having suffered an alteration in their genetic. The organism itself takes care of repairing any genetic alteration.
- If the change is maintained a mutation is produced.
- The positive mutations constitute the mechanism of natural selection which explains the evolution of living-beings.
SUMMARY |
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