Final answer:
Proteins have directional ends known as the N-terminus and C-terminus, making the statement about protein directionality true. The N-terminus and C-terminus are key to protein function and structure.
Step-by-step explanation:
Proteins are indeed directional, featuring a chemically distinct beginning and end. The answer to the question is a) True. The distinct ends are referred to as the N-terminus and C-terminus. The N-terminus has an amino group (-NH2) while the C-terminus has a carboxyl group (-COOH), and this directionality is crucial to protein function and structure.
Regarding the information provided:
- Cells do not produce proteins from every gene they possess at all times, which makes statement 29 False.
- Statement 30 about the lagging strand requiring more primers than the leading strand during DNA replication is True.
- As for statement 31, the genetic code has redundancy, meaning some amino acids are encoded by more than one codon; it is False that each codon encodes a different amino acid.
Proteins can be recycled when they are no longer needed or when they need to be repurposed, which involves breaking down the protein into its constituent amino acids.
The unique sequence of amino acids in proteins leads to their distinct three-dimensional structures, which are crucial for their specific functions in the body.