DNA basics Flashcards
1
Q
Parts/ structure of the nucleus
A
- Nuclear envelope (double membrane) with pores
- Nucleolus
- Chromatin network (DNA and proteins)
2
Q
The general structure of DNA
A
- A very long molecule
- Double strand resembling a ladder
- Twisted into a helix (I.e. a double helix)
3
Q
what is a polymer?
A
A molecule that contains monomers which are similar units or building blocks
4
Q
The monomer of DNA?
A
nucleotides
5
Q
Nucleotides are made up of?
A
- A phosphate
- A deoxyribose sugar
- A nitrogenous base
6
Q
The different nitrogenous bases of DNA.
A
- A adenine
- T thymine
- C cytosine
- G guanine
7
Q
Purine bases
A
- Larger
- A and G
8
Q
Pyramidines
A
- smaller
- C and T
9
Q
The pairing of nitrogenous bases of DNA and how many bonds for each?
A
- A with T (2 H-bonds)
- G with C (3 H-bonds)
10
Q
The name of the bonds between nitrogenous bases in DNA?
A
Hydrogen bonds
11
Q
Mutation
A
Change in the sequence of nucleotides in DNA
12
Q
True or false: mutations are always harmful
A
False
13
Q
Types of mutations
A
- Point: single nucleotide change
- Substitution: replacing one (or more) nucleotide(s) with another
- Deletion: deleting one (or more) nucleotide(s) from the DNA
- Insertion: adding one (or more) nucleotide(s) into the DNA
14
Q
Frame shift
A
A change in the way codons are read because nucleotide triplets shift as a result of a deletion or insertion
15
Q
Causes of mutations
A
- exposure to radiation,
- viruses,
- faulty copying during transcription
