Chapter 4 Flashcards
The monomer unit of DNA and RNA is the
Nucleotide which contains: nitrogenous base, 5-carbon sugar, phosphate group
DNA and RNA are polymers called
Polynucleotides
How is a sugar-phosphate backbone formed?
Covalent bonds between the phosphate of one nucleotide and the sugar of the next nucleotide
What is the structural difference between a DNA nucleotide and RNA nucleotide
RNA has a OH on carbon-2. DNA only has H to prevent bonding and create double helix shape
Pyrimidines
Thymine and cytosine
Purines
Adenine and guanine
Which bases create a less stable bond
Adenine and thymine because they have 2 hydrogen bonds
What kind of model does DNA replication follow
Semiconservative
Where does DNA replication begin?
Origins of replication
In which direction does continuous DNA replication occur
5’ →3’
In which direction does non-continuous DNA replication occur
3’ → 5’
How can the information for specifying an organism be carried in chemical form, and how is it accurately copied?
Replication
What contains the instructions for producing proteins?
Genes
- the sequence of nucleotides spell out the sequence of amino acids in a protein
What is gene expression?
A cell converts the nucleotide sequence of a gene first into the nucleotide sequence of an RNA molecule, and then into the amino acid sequence of a protein
What is the most important function of DNA
To carry genes
Packaging DNA by specialized proteins that bind to and fold the DNA generates
Coils and loops
What makes DNA negatively charged
Phosphate group
DNA being compacted keeps it available to
The many enzymes that replicate it, repair it, and use its genes to produce RNA and proteins
The human genome has how many nucleotides?
3.2 x 10^9
The complex of DNA and protein is called
Chromatin
What are basic dyes?
Stain the nucleic acids and proteins in the cell nucleus
- catatonic (+ charge)
Condensed form of chromatin
Chromosome
Maternal and paternal chromosomes are called
Homologous chromosomes
How to distinguish one chromosome from another
Stain with dyes
The display of the 46 human chromosomes at mitosis is called
The human karyotype