Chapter 2: Structure, Function, and Inheritance of the Human Genome Flashcards
Within a haploid nuclear genome, how many base pairs are there?
3200 Mbp
In a diploid cell, how many copies of the haploid genome are there?
2
How many chromosomes are there per diploid cell?
46
A diploid, somatic cell consists of:
- nucleus
- cytoplasm
- mitochondrion
How many mitochondrion are there in a diploid cell?
100s to 1000s
Mitochondrial DNA (mtDNA) is how many base pairs long?
16 569 bp
How many copies of mtDNA are there per mitochondrion?
2 - 10 copies
How many copies of mtDNA are there in a diploid cell?
1000s of copies per cell
What is the shape of mtDNA?
circular molecule
Which bases are purines?
adenine and guanine
Which bases are pyramidines?
cytosine and thymine
Each base is joined to:
a sugar molecule, deoxyribose
Each deoxyribose has:
a phosphate group attached to it; the sugar and phosphate only play a structural role in DNA and carry no information
What is methylation?
Modification of a cytosine base in DNA by the addition of a methyl group, to yield 5-methylcytosine; methylation of other bases occur in other organisms.
Methylation plays a role in:
gene regulation
The phosphate of one nucleotide is joined to the sugar of another, and so on, and this forms the:
sugar-phosphate backbone of DNA
Because the deoxyribose group itself is asymmetrical, it provides __ to the backbone.
polarity
The end of a DNA or RNA molecule bearing a free hydroxyl (-OH) group (unattached to another nucleotide) on the 3’ carbon
3’ end
The end of a DNA or RNA molecule bearing a free hydroxyl (-OH) group (unattached to another nucleotide) on the 5’ carbon
5’ end
What is replication?
The copying of a double-stranded DNA molecule to yield two double-stranded daughter molecules
What is translation?
The production of a protein from an mRNA molecule within the ribosome
What is transcription?
The production of an RNA molecule from a gene (DNA)
Strong chemical bonds between atoms in a molecule requiring considerable energy to be broken
covalent bonds
Weak inter-atomic bond either within a molecule or between molecules; these are the bonds between bases in a base pair of DNA
hydrogen bond
What is denaturation?
The separation of the strands of DNA, often by heating or treatment with alkali; in PCR, the first stage of a cycle, in which the temperature is typically 94 C
How many hydrogen bonds are there between a G and a C?
3
How many hydrogen bonds are there between an A and a T?
2
The higher the number of hydrogen bonds between bases:
the more energy is needed to denature
