- Created by: lisa.millerx
- Created on: 09-11-16 16:11
DNA, Genes and Chromosome
- Nucleus- Controls the activitie of the cell and has genetic information.
- Chromosome- Contains the genetic information - 23 pairs of these in humans. 46 in total.
- Genes- carries the code to make one proteien - sections of a chromosome.
- DNA- Contains coded information
Structure and function of DNA
- Chromosomes are made of DNA.
- DNA is found in the nucleus and carries the genetic instructions to amke proteins.
- DNA is described as a double helix - made of two strands which are twisted.
- The strands are joined by bases - four types of bases- A + T G + C
The sequence of bases determines the sequence of amino acids which determines the structure and function of the protein.!!!!!!!!!!!!!!!!!!!!
- A section of DNA is called a gene.
- Each gene codes for a specific protein.
- Proteins are very important becasue they determine the characteristics of the organism.
- Proteins are made by a chain of amino acids (joined by peptide bonds).
- mRNA carries a copy of the gentic code from DNA in the nucleus to a ribosome in the cytoplasm. (Ribosomes are where protein is made)
Stages of protein synthesis
1. DNA unwinds and a single-stranded complementary copy of it is produced, called mRNA.
2. mRNA carries the copy of the code from the nucleus to a ribosome in the cytoplasm.
3. At a ribosome, amino acids are placed in order, according to eacjh triplet of bases on mRNA.
4. Amino acids join together by peptide bonds to make a protein!