inheritance Flashcards
what is a chromosome
a tightly packed DNA around histone proteins
what is a gene
a section of DNA that codes for a protein
the structure of DNA
- it is a polymer made of many nucleotide monomers
- it is made of 2 strands in the shape of a double helix
what are the four bases
adenine, thymine, cytosine, and guanine
describe the process of transcription
- DNA unzipped
- complementary mRNA nucleotides bind and join together
-mRNA detaches and leaves the nucleus
what is a codon
a group of three bases on the mRNA molecule that code for a single amino acid
what is an anticodon
three bases on a tRNA molecule that match the codon on the mRNA molecule
describe the process of translation
- mRNA travels to a ribosome
- tRNA molecules with an anticodon that matches the codon on the mRNA molecule carry amino acids to the ribosome
- the amino acids are joined together
what is a dominant allele
a version of a gene where only one copy is needed for it to be expressed
what is a recessive allele
a version of a gene where two copies are needed for it to be expressed
what is a homozygous organism
it has two copies of the same allele eg. two recessive
what is a heterozygous organism
it has two different versions of the same gene (one of each)
what is co-dominance
when two alleles affect the phenotype
which three processes require mitosis
- growth
- repair
- asexual reproduction
what does mitosis produce
one parent cell produces two daughter cells
what does meiosis produce
one parent cell produces four daughter cells
what the differences between mitosis and meiosis
mitosis produces 2 genetically identical cells but meiosis produces 4 genetically different cells
mitosis produces diploid cells but meiosis produces haploid cells
how do mutations alter the phenotype
- mutations alter the genetic material (DNA)
- this can cause it to code for a different sequence of amino acids
- a different sequence of amino acids means that the protein will be different
