d3.2 inheritance Flashcards
monohybrid influence
only one trait
in the same pair of chromosomes (alleles)
diff version of the alleles
2 alleles
determine what the characteristic should be
single-nucleotide polymorphism
can cause different alleles in the gene pool
single nucleotide polymorphism eg
blood type
genotype
alleles responsible for the characteristics
eg. BB
phenotype
characteristic expressed due to the alleles in the dna and the environment
discrete variations
either this or that
discrete variations eg
male or female
dominant
- usually the dominant allele codes for a protein that is active and carries out a function
- always expressed in the offspring
co-dominant
pair of alleles are both expressed
homozygous
alleles for the characteristics are the same
eg. BB
heterozygous
alleles for the characteristic are different
eg. Bb
how to figure out genotype
cross with homozygous recessive organism
1:1 = heterozygous dominant
1:3 = 2 heterozygous
recessive
- usually the recessive allele code for a non-functional protein
- may not be expressed in the offspring
allele
different versions of genes that contain information for the same characteristics
eg. eye colour
chromosome
made of dna and protein (histone) and contains genes
genes
heritable factors that control specific characteristics
gene locus
specific position of a gene on a chromosome
homologous
same loci same gene
how to say location of gene locus
chromosome number
p- short arm
q- long arm
number- bands away from the centromere
autosomal recessive disorder
not on the chromosome that determines gender
autosomal dominant disorder
achondroplastic dwarfism
sex linked recessive eg
haemophilia
- x linked