Search for notes by fellow students, in your own course and all over the country.
Browse our notes for titles which look like what you need, you can preview any of the notes via a sample of the contents. After you're happy these are the notes you're after simply pop them into your shopping cart.
Document Preview
Extracts from the notes are below, to see the PDF you'll receive please use the links above
CHAPTER
3
Genetics
deals with inheritance and variation of characters
from parents to offsprings
...
Variation
is the degree by which progeny differ from their
parents and is caused due to sexual reproduction
...
Mendel selected 14-true breeding pea plant varieties as pairs
which were similar except for one character with contrasting
traits
...
Law
of dominance explains the expression of only one
parental character in F1 of monohybrid cross
...
Monohybrid
cross is a cross between two organisms which
is made to study the in heritance of a single pair of alleles of
character
...
Dihybrid
cross is a cross between two organisms which is
made to study the inheritance of two pairs of alleles belonging
to two different genes
...
Law of segregation explains, the factors or alleles of a pair
segregate from each other such that gametes receive only one
of the two factors
...
If F1 did not resemble either of the parents and was in between
the two this type of interaction is called as incomplete
dominance, e
...
, dog flower (Snapdragon or Antirrhinum
sp
...
Genes are units of inheritance
...
British geneticist R
...
The alleles which do not show dominance-recessive
relationship and are able to express themselves independently
and equally when present together
...
ABO blood group in human being is controlled by Gene-I,
having three alleles IA, IB and i
...
IA and IB are completely dominant over i, but when IA and IB
are present together, they express their own sugars, because
of co-dominance hence RBC have both sugars
...
ABO blood grouping is a very good example of multiple
allelism in which more than two alleles govern the same
character
...
It is the effect of a gene
on metabolic pathways which contribute towards different
phenotypes, e
...
, Phenylketonuria
...
Sutton
united the knowledge of chromosomal segregation
with Mendelian principles and proposed chromosomal theory
of inheritance
...
Morgan proved and defined linkage on the basis of his
breeding experiments in Drosophila melanogaster
...
Morgan's
If traits are controlled by three or more genes then the traits are
called as polygenic traits
...
The phenotype reflects the contribution of each allele,
i
...
, the effect of each allele is additive, e
...
Human Skin
Colour
Types
of sex-determination
...
g
...
g
...
g
...
In honey bees, sex-determination is haplo-diploid type in
which unfertilised egg develops as male (drone) i
...
haploid
and Queen and worker bees (females) are diploid
...
Chromosomal
aberrations are commonly observed in cancer cells
...
g
...
Pedigree analysis is a study of family history about inheritance
of a particular trait or disease
...
A few disorders are Downs's syndrome, klinefelter's
syndrome, Turner's syndrome
5