C10.1: Heredity Flashcards
what is genotype
-your DNA resulting in your genetic makeup
what is phenotype
-what genes are expressed
what is an allele
what are the 2 basic characteristics of an allele?
variant of a gene due to changes in sequencing
- Dominant - affects the phenotype when present in 1 copy
- Recessive- must be present in 2 copies to be expressed
what is a pungent square
-maps of statistical chance of inheriting a condition
how many pairs of chromo for humans
23 pairs, 46 individual (44 autosomes and 2 sex chromo)
what is meiosis
- involved 2 divisions of genetic material and produces 4 haploid cells
- the 4 cells will each have a new assortment of genes and chromo
list the 4 modes of inheritance
- autosomal dominant
- autosomal recessive
- sex linked dominant
- sex linked recessive
describe homogenous and heterogenous in terms of alleles
homo: individual w/ 2 identical alleles for a gene
hetero: individual w/ 2 different alleles for a gene
are recessive or dominant disorders typically more severe
-recessive are more severe and usually produce symptoms at a much earlier age
are dominant disorders w/ early presentation more or less commonly seen?
less commonly because these people tend to be too sick to reproduce
why are dominant disorders w/ late presentation more common?
these individuals can reproduced so the gene is passed on
what is uniparental disomy
-2 copies of an allele from one parent
what are X linked recessive traits
give an example
- always passed from mother from son (son will have the disease)
+ hemophilia A is an example
-daughters are carriers since hemophilia is recessive
when can hemophilia be expressed in girls
-if mom is a carrier and the father had a disease
what is Klinefelters syndrome (XXY)
how does it effect a male?
-affects males who have an extra X chromo passed on from their mother
- will be underdeveloped sexually (no pubic hair or facial hair, may develop breast tissue)
- long arms, legs, large hands and feet
