Variability

marks.

factors of the external environment without genotype change
these signs are

not inherited
to the organism's adaptation to the living environment.

Phenotypic variability (modification).

the laws of phenotypic behavior is crucial for medical practice,

which allows to determine the role of factors in the formation of phenotype of the environment or their aggregates.
Knowledge of the phenocopies to the doctor:
a) make a correct diagnosis;
b) to give a more accurate forecast of the condition of the disease and to determine the possibility of future illness in the same family.

Importance of modification changes.

of environmental factors, adapt to the environment, but they will

come back when the effect of the reversible enviromental factor is eliminated. For example: Reduction of erythrocytes in the blood when oxygen content is reduced.

varies within a range of reaction rates from a minimum

to a maximum. The explicit threshold of the modification variability with the genotype is called the reaction rate. The reaction rate is controlled by genetic factors and is inherited.

For example: the size of wooden leaves
Changes in human digital symbols. Digital Signs:
Intensity of skin color
Blood pressure, erythrocytes in the blood
Weight e.t.c.

material), the variability is inherited and independent of the factors

in the external environment .

Genotypic variability

Combinative variability

Mutation variability

genes. In combinative variability, the combination of parent gametes results

in new combinations of genes, but these genes and chromosomes do not change. A random addition of gametes during fertilization

Mechanisms of combinative variability

Provides diversity of biological species, diversity of species and their viability.
For example: diversity of people, diversity of children in one family

of external and internal factors.
The mutation is accompanied by the

change in the genotype of the phenotype and is transmitted from generation to generation.
Mutations develop suddenly and leap.
This term was introduced in science. De Frise (1901)

Mutation variability

are called mutagenic factors.
Mutation variability
Mutagenic factors
Physical Factors
Chemical Factors
Biological Factors

organic and inorganic substances (nitrates, alkaloids, hormones, enzymes, etc.);
     b) Production

products of natural compounds (oil);
     c) synthetic substances (medicines, pesticides, food preservatives, insecticides, paints) and so on.
Biological: a) viruses (measles, rubella, influenza) b) parasitic agents (bacteria, rickettsia, simple, gelments).

Mutagenic factors

under the influence of natural mutagenic factors without the presence

of human beings;

Induction or artificial mutations - develop under the influence of known mutagenic factors (with human participation).

Classification of mutations

leading to hereditary diseases.
lethal mutations (deadly)
subletal mutations (reduces vitality)
Neutral mutations

do not affect their survival, such as eye color, blood group.
Useful mutations increase the vitality, for example, the formation of resistance of cockroaches to toxic chemicals.

Classification of mutations