genetics- DNA Flashcards
DNA is an abbreviation for:
deoxyribonucleic acid
DNA stores what?
genetic information
differences in DNA result in:
variations in characteristics and allow organisms to evolve
nucleotides are:
basic building blocks of nucleic acids
the three main types of nucleus acid are:
DNA
RNA
ATP
nucleotides consist of three components, they are:
a phosphate group
a sugar
a nitrogenous base
the four nitrogen bases in DNA are
adenine (A)
cytosine (C)
guanine (G)
thymine (T)
What are the characteristics of the DNA molecule
two strands of nucleotides
twisted ladder(double helix) structure
sides of ladder are made up of sugar and phosphate groups covalently bonded
rung of ladder is made of two complementary nitrogenous bases held together by hydrogen bonds
what type of bond do sugar and phosphate groups have
covalent bond
what type of bond holds together complementary nitrogenous bonds
hydrogen bond
what is the name for nitrogenous bases that pair together
complimentary bases
parents pass DNA to their?
offspring
what does DNA code for
specific proteins
a complete sequence of DNA is called a ____
genome
during interphase, DNA exists as:
condensed fibres called chromatin
during mitosis, DNA is:
in a very condensed form called chromosomes
how many chromosomes are in human somatic cells
46
what cells are the chromosomes located in?
somatic(body) cells
chromosome pairs:
how many?
function?
23 pairs
one pair is the sex chromosomes
other 22 are called autosomes
Define: Homologous Chromosomes
a chromosome that contains the same sequence of genes as another chromosome
they are not identical to each other
Define: Gene
a specific section of a chromosome that governs the expression of a trait and is passed on to offspring
Define: Allele
a different form of the same gene
Define: Karyotype
a photograph of pairs of homologous chromosomes in a cell
the chromosome pairs are arranged and numbered in order of their length from longest to shortest
the sex chromosomes are placed last
a cell does what with its DNA once in the cell cycle?
replicates or copies
Define: DNA Replication
a process that makes identical copies of a DNA molecule
Each new DNA molecule consists of:
an original parent strand and a new daughter strand
What DNA is used to produce?
RNA from specific genes using transcription
RNA is translated to produce what?
a protein
The sequence of bases in the DNA molecule determines what?
the specific sequence of amino acids in the protein molecules
