BASIC TERMINOLOGIES OF GENETICS
Genetics
Genetics
is the study of genes and heredity it include the study of basic units of
heredity, genes, and other transmission of genetic information from one
generation to the next.
Heredity
Heredity
is the passing of characteristics, traits; genetic information from one generation
to next by genetic material is called heredity. Parent’s information and
children information can be collected from the heredity material. Children’s
have those characteristics that have in theirs parents. Heredity is to blame
for the similarities between parents and their children since offspring inherit
genetic instructions from their parents, altering characteristics of their
physical appearance, behavior, and susceptibility to specific diseases.
Variation
in genetics
Variation
describes the distinctions or diversity found between individuals within a
group or among members of a species. These variations may be in terms of
appearance, conduct, or genetic make-up.
Gene
An
essential component of heredity, a gene is a section of DNA (deoxyribonucleic
acid) that carries the genetic code of living things.
Cells
Cells
are the fundamental structural and functional units of life. They are the basic
building blocks of all living organisms.
.png "Gene and chromosome")
Cell division
The
process through which a single cell splits into two or more daughter cells is
known as cell division. It is necessary for the development, maintenance, and
procreation of living things.
Cell
division primarily takes place in two ways:
1.
Mitosis: Multicellular organisms that have somatic (body (not gametes (sperm or egg)) cells go through a process of cell
division called mitosis. Two identical daughter cells are created as a result,
each with the same number of chromosomes as the parent cell.
2. Meiosis: Meiosis is a specific kind of cell division that takes place in
sperm and egg cells, which are reproductive cells. It produces four different
daughter cells by half the number of chromosomes.
.png "Mitosis and Meiosis")
MENDELIAN GENETICS
Gregor
Mendel created Mendelian genetics the theory of genetic inheritance in the
1800s.
Law
of segregation: “During
gamete formation - alleles for each gene segregate (Isolate) from each other,
so that each gamete carries only one (1) allele for each gene.”
Male
gametes (sperm), and female gametes (eggs), are two gametes in animals. Male (pollen)
and female (ovules) are the two gametes in plants.
Allele:
Allele is an alternative form of a gene present on a specific location of
chromosome.
Law
of independent assortment: “When gametes
are formed, different characteristics genes can segregate independently.”
CHROMOSOME THEORY OF HEREDITY
The
Sutton-Boveri theory, commonly referred to as the chromosomal theory of
heredity, is an essential idea in genetics that shows a clear connection
between chromosome behaviour and the laws of Mendelian inheritance. In the
early 20th century, Walter Sutton and Theodor Boveri separately proposed this
theory, which served as a vital link between Mendel's research on the
inheritance of traits and the developing field of cellular biology.
The main principles of the
chromosome theory of heredity are as follows:
Chromosomes
Carry Genetic Information: T According to the concept, chromosomes—thread-like structures
discovered in the nucleus of eukaryotic cells—carry the genetic material
required for the transmission of traits. Genes, which are particular sections
of DNA on chromosomes, are where this genetic data is stored.
Mendel's
Laws and Chromosomes: The idea
correlates the activity of chromosomes during cell division, particularly
during meiosis (the process of gamete production), with Mendel's concepts of
inheritance (such as the segregation of alleles during gamete formation and the
independent assortment of genes).
Homologous
Chromosomes: One chromosome
from each parent is inherited in each pair of homologous chromosomes, which are
the only chromosomes that exist in pairs. The same features are encoded by various
alleles on these homologous chromosomes.
Alleles
Segregate during Meiosis: Allele
segregation is ensured during meiosis when homologous chromosomes divide into
different gametes. In line with Mendel's Law of Segregation, this occurs.
Independent
Assortment: Mendel's Law
of Independent Assortment is in agreement with the independent assortment of
genes on various chromosomes during meiosis. Offspring are produced as a
result, and they are genetically diverse.
Chromosome
theory of inheritance brought together the knowledge of how traits are passed
down through the genetic and cellular levels. It included a thorough
explanation of where genes are found on chromosomes, how they are passed down
through the generations, and how genetic variety develops. This theory served
as the foundation for contemporary genetics and our knowledge of the molecular
causes of heredity, including ideas like chromosome mapping and genetic
linkage.