Unit 1: DNA and the Production of Proteins Booklet Key Points Flashcards
What is the function of the nucleus?
Controls the activities of the cell
What does a chromosome contain?
The genetic information
How many pairs of chromosomes are in humans?
23 pairs
What does a gene carry?
The code to make one protein
What is a genes other form called?
Alleles
What does DNA contain?
Coded information
What is the structure and function of DNA?
Chromosomes are made of DNA. DNA is found in the nucleus and carries the genetic instructions to make proteins. DNA is known as the double stranded helix. It is made of two strands which are twisted into a helix. The strands are joined by bases. DNA is made of four types if base: adenine(A), thymine(T), guanine(G), and cytosine(C)
How are DNA bases paired.
C(Cytosine) pairs with G(Guanine)
A(Adenine) pairs with T(Thymine)
What is a gene and what does it do?
A section of DNA is known as a gene. A gene codes for a protein which determines the characteristics of the organism.
What are proteins?
Proteins are complex molecules made of a chain of amino acids
What does the order of amino acids in DNA determine?
The order of amino acids coded in the DNA sequence of the gene which determines the order of the amino acids in the protein and therefore it’s structure and function.
Why is mRNA needed?
Chromosomes are very large and can contain more than a thousand genes. It is difficult to change genes into proteins without having some sort of go-between. This is provided by mRNA.
What is mRNA and what does it do?
Each mRNA is a copy of a single gene. mRNA carries a complementary copy of the genetic code from chromosomal DNA in the nucleus to a ribosome in the cytoplasm so the amino acids can be assembled into proteins.
What are the steps involved in synthesising a protein?
Instructions in nucleus
mRNA takes a copy of one gene
Messenger RNA carries a complementary copy of the genetic code from the DNA in the nucleus to the ribosomes.
Assembly of amino acids into protein ribosomes.
