Genetics Flashcards
Father of genetics
Gregor Johann Mendel
The branch of science which deals with hereditary
Genetics
The chromosomes responsible for sex determination
sex chromosomes
A hereditary disease in which blood does not clot
Haemophilia
The unit of hereditary
Gene
Number of pairs of autosomes in humans
22 pairs
The condition in which both alleles are identical
Homozygous
Monohybrid phenotypic ratio
3:1
The chemical substance which constitute genes
DNA
The allele which express itself on the other
dominant allele
One genetic disease
Haemophilia
The genetic make up of an organism
Genotype
The cross between one pair of contrasting characters
Monohybrid cross
Two sex linked inherited disease
Haemophilia, colour blindness
The plant on which Mendel had worked
Garden Pea plant (Pisum Sativum)
The type of allele which expresses itself only in homozygous state
recessive
A sudden heritable change in the gene
Mutation
The part of gene responsible for a particular characteristics in an individual
Allele
Genetics is the study of transmission of
characters
The small differences among individuals
Variations
Dihybrid Phenotypic ratio
9:3:3:1
Upon ______________ diploid condition is restored
fertilisation
Phenotype is the observable character ____________ controlled
genetically
A quality or characteristic that can belong to only one person
trait
What is gene?
Basin unit of hereditary, located on the chromosome
Which one of the following is the phenotypic monohybrid ratio in F2 generation
3:1
If a pure tall plant is crossed with a pure dwarf plant, then offspring will be
all tall
The 9 : 3 : 3 : 1 dihybrid ratio is due to
independent assortment
A plant with green pods and smooth seeds with genotype Ggss will give rise to the following gametes
Gs and gs
The disease colour blindness is a
Recessive X-linked disease
The physical expression of a character is called
Phenotype
Purity of gametes is linked to
Law of segregation
The phenotypic dihybrid ratio of F2 generation is
9:3:3:1
If the mother is normal and the father is haemophilic, then their two daughters will be
carrier
Study of laws of inheritance of characters
Genetics
Autosomes
Chromosomes other than the pair of sex chromosomes
A gene that can express only when in a similar pair
Recessive gene
The alternative forms of a gene
Allele
Homologous chromosomes
Chromosomes similar in size and shape
Which one of the following genotypes is homozygous dominant and which one homozygous recessive in regard to tongue rolling:
Rr, rr, RR
Homozygous recessive – rr
Homozygous dominant - RR
Duplicated chromosomes remain attached at a point termed as
centromere
The full complement of DNA of an organism is termed as
Genome
The inheritable feature of an organism is termed as
character
__________ flower position is a dominant trait of pea flower.
Axillary
Law of Dominance
Out of a pair of contrasting characters present together, only one is able to express itself while the other remains suppressed. The one that expresses is the dominant character and the one that is unexpressed is the recessive one.
Law of Segregation
aka the law of purity of gametes.The two members of a pair of factors separate during the formation of gametes. They do not blend but segregate or separate into different gametes. The gametes combine together by random fusion at the time of zygote formation
Law of Independent Assortment
When there are two pairs of contrasting characters, the distribution of the members of one pair into the gametes is independent of the distribution of the other pair.
