DNA and the production of proteins Flashcards
What does the nucleus carry?
The nucleus of the cell carries genetic information in structures called chromosomes.
What do chromosomes contain?
Chromosomes contain DNA (DeoxyriboNucleic Acid) which consists of extremely long, extremely thin double strands.
What is a gene?
A gene is a section of DNA(100s to 100s of bases long) which codes for making a protein to give you a characteristic e.g. eye colour
Describe what a nucleotide is.
Each strand of DNA molecule is made up of repeating units/building blocks called nucleotides. nucleotides have three parts: a deoxyribose sugar molecule; a phosphate molecule and a base molecule.
What is different about each DNA nucleotide?
Every DNA nucleotide has the same type of sugar and phosphate but the bases can be of different.
What are the four different DNA bases?
A) adenine
T) Thymine
G) Guanine
C) Cytosine
What function do the bases have?
The base sequence determines the amino acid sequence in proteins
What are the sugar of one nucleotide and the phosphate of another nucleotide, above it or below it, held by?
The sugar of one nucleotide and phosphate of another nucleotide, above it or below it, are held together by strong bonds (sugar-phosphate) and form the backbone of the DNA molecule.
How does the base of one single strand of nucleotide pair with another?
The bases of the single strand of nucleotide form weak bonds with bases of an opposite strand, holding two strands together. A base will only pair with its complementary partner so adenine always pairs with thymine (A=T) and guanine with cytosine(G=C).
What is a sequence of bases unique to?
The sequence of bases along the DNA strand is unique to an organism.
What are proteins made up of?
Proteins are made up of many subunits called amino acids linked together in long chains by peptide bonds. Each protein has its own sequence of amino acids.
What does the sequence of amino acids determine for the protein?
The sequence of amino acids determines the structure and function of the protein.
How many bases are needed to code for one amino acid?
A group of three bases is the code for one amino acid.
How does the sequence of bases code for making a protein?
Each group of three DNA bases on a strand is the code for one amino acid. So the order of DNA bases determines the sequence of amino acids in the chain which determines the structure of the protein. The structure of the protein determines its function.
What is the role or function of the molecule names messenger RNA (mRNA)?
The genes(for making the protein) are in the nucleus but ribosomes (where proteins are made) are in the cytoplasm. This means the information to make a protein must be carried from the DNA in the nucleus to the ribosomes in the cytoplasm. This is done by a molecule called messenger RNA (mRNA).
