Control Of Gene Expression Flashcards
Describe proteins
- Made up of amino acids
- There are 20 amino acids in the human body.
- They are absorbed from the products of digestion.
How is the phenotype (physical appearance) of an organism determined?
By the protons produced as a result of gene expression.
What does gene expression involve?
The process of :
Transcription and
Translation
How can gene expression be influenced?
By intra- and extra- cellular factors (environmental factors from both inside and outside the cell)
What is the genetic code used in transcription and translation found in?
All forms of life
How many of the genes are expressed?
Only a fraction of the genes in a cell are expressed depending on the proteins required by that cell.
Describe the structure and function of proteins
- amino acids are linked together by peptide bonds to form polypeptide chains.
- Polypeptide chains fold to form the 3-dimensional shape of a protein
- These folds are held in place by weak hydrogen bonds and other interactions between amino acids.
- The shape of a protein is linked to its function.
- Proteins have a large variety of structures and shapes resulting in a wide range of functions.
What is DNA a type of?
Nucleic acid
What is another type of nucleic acid?
RNA
What is RNA
Ribonucleic acid
Describe the structure of RNA
RNA is a single stranded molecule that consist of a sugar-phosphate backbone and the 4 bases: cytosine (C), Guanine (G), Adenine (A) and Uracil (U). The sugar found in an RNA nucleotide is called Ribose.
What are the types of RNA?
There are 3 types of RNA:
- mRNA (messenger RNA)- carries a complementary copy of the genetic code from the DNA in the nucleus to the ribosomes of the cytoplasm.
- tRNA (transfer RNA)- carries specific amino acids to ribosomes.
- rRNA (ribosomal RNA)- combines with proteins to make up the structure of ribosomes.
