Genetics revision PART 2 TEST Flashcards
What is the subunit called that makes up DNA
Nucleotide
Name the four base pairs and state the base paring rule
Adenine pairs with Thymine
Cytosine pairs with Guanine
What is mitosis
division of diploid somatic cells into 2 identical cells, for growth and repair
what is meiosis
Is the process by which the gonads produce haploid gametes. (Sex cells)
Contrast mitosis and meiosis
Mitosis only involves one cell division and produces two daughter cells.
Where as Meiosis involves two cell divisions but produces 4 duaghter cells.
Are the daughter cells identical or different to the parent cells.
In mitosis the duaghter cells are identical to the parent cells.
In meosis the daughter cells are different to the parent cells.
What is an allele?
Allelles are versions of a gene that code for a same trait
how many chromsomes in a human body cell
46
is a body cell haploid or diploid
diploid
Contrast between genotype and phenotype
Genotype refers to the genetic characteristics of an organism . Examples of genotype are eye colour and height
Phenotype refers to physical characteristics or traits like appearances
define genotype
the combination of alleles inherited for a particular characteristic.
define phenotype
outward expression, appearance, description of a characteristic
Homozygous
a genotype in which the two alleles are identical, (BB bb)
Heterozygous
a genotype in which the two alleles are different (Bb)
how many pairs of homologous chromsomes do human females have
23 homologous
