Accessing and Manipulating Biological Databases Exercises (Part 2)

In the exercises below we cover how we can Access and Manipulate Biological Data bases through rentrez & Seqinr packages

Install Packages
rentrez
seqinr

Answers to the exercises are available here.

If you obtained a different (correct) answer than those listed on the solutions page, please feel free to post your answer as a comment on that page.

Exercise 1
Read a Fasta File in your current directory and print the sequence

Exercise 2

Read a Fasta File in your current directory and print the length of the sequences

Exercise 3

Read a Fasta File in your current directory and count each nucleotide in the file.

Exercise 4

Read a Fasta File in your current directory and print the details of the sequences
Exercise 5

Read a Fasta File in your current directory and count all dinucleotides in the file.

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Exercise 6

Read a Fasta File in your current directory and print the GC contents

Exercise 7

Read a Fasta File in your current directory and print sequences as characters.

Exercise 8

Open the Nucleotide Fasta file and translate the sequences to Amino acids in Forward Translation

Exercise 9

Open the Nucleotide Fasta file and translate the sequences to Amino acids in Reverse Translation

Exercise 10

Open the Nucleotide Fasta file and translate the sequences to Amino acids and print the three letter codons of the translated amino acids