There are lot of words used in genetics but I'll only be talking about the most important ones. Let me get going:
1.Genes: The genes are known to be the basic unit of inheritance. You can also call them the carrier as they carry the transmittable characters of a person. They are responsible for the transmission of characters from parent to offspring and their site is the chromosome.
2.Homozygous Gene: This is a pair of similar genes or identical alleles. For example, a person can possess homozygous genes for tallness(TT) or shortness (tt).
3.Heterozygous Gene: This is a pair of contrasting genes or non-identical alleles. For example, a man that is not too tall or short possesses an heterozygous gene for tallness which is Tt.
4.Dominant Gene: This is a gene that always find expression wherever it appears even in the presence of a contrasting gene. These are responsible for the noticeable traits found in a person formed out of two contrasting genes. For example if a tall man marries a short woman and they gave birth to a short son, the genes of shortness (tt) is said to be dominant.
5.Recessive Gene: These genes do not express themselves although they are not lost. Allow me to define this as the gene that will only express itself in the absence of a contrasting gene. For example if a tall man marries a short woman and they gave birth to a short son, the genes of tallness (TT) is said to be recessive.
6.Chromosomes: These are the houses of the genes, they are thread-like bodies found in the nucleus of a cell. There are 23 pairs of chromosomes in a man and 46 unpaired. Of the 23 chromosomes, 22 are autosomes and the 23rd is the sex chromosomes.
7.Traits: These are the characters or feature of a person that is transmittable to its offspring. Example of this include: Height, Skin Colour e.t.c
8.Gamete: These are the haploid matured sex cell that take part in sexual reproduction. The male gametes are spermatozoon and pollen grains in animals and plants respectively while the female gametes are ovum and ovules in animals and plants respectively.
9.Zygote: This is rather defined as a diploid cell resulting from the fusion of two haploid gametes(a single male and a single female). It can also be said to be the single cell that results from the union of 2 gametes usually male and female.
10.Alleles or Allelomorphs: This is a pair of genes that control a contrasting pair of genes or character. They are called allelic pair and a single one is called an allele.
11.Phenotype: This is the physical composition of an individual. It refers to the physical expression of an organism. E.g Eye, Body Shape...These are morphological variations.
12.Genotype: This refers to the traits obtained by an organism from the parent and it is meant when they say genetic make up or constitution. It is known as the internal composition of an individual as the traits here can only be known as conduction of a test or series of tests.
13.Fillial Generation: These are the offsprings given birth to by a parent from generation to generation. where a couple give birth to 3 or 4 children known as the 1st fillial generation, F1.
The first Fillial generation gives rise to the Second and the second gives rise to the 3rd. This means we have 3 fillial generations, the first, the second,l and the third.
14.Hybridization: This is the crossing of two contrasting or unrelated organisms to produce a sterile offspring. This is majorly done to produce a better organism than the two organisms that produced it. For example:
Credit
A liger is gotten from a male lion and female tiger(tigeress). They enjoy swimming, a characteristic of tiger and they are very sociable just like lions. They grow bigger than both lions and tigers.
Monohybridization is the crossing of a pair of genes with an opposite pair of genes. For example:
TT X tt
While Dihybridization is the crossing of 2pairs of genes with an opposite 2 pairs of genes. For example:
TTBB X ttbb
15.Hybrid: This is the product of hybridization. The organism produced after the cross of two unrelated organisms is called a Hybrid.
16.Locus: This is the point where a gene is located in the chromosome.
17.Haploid: This is when an organism has only one set of chromosomes in the gamete. The matured gamete is usually haploid. The haploid is usually represented by a small alphabet (n).
18.Diploid: This is when an organism has two set of chromosomes in the body cell. All plants and animals are diploid. The diploid is usually represented by 2n because it is double the haploid number.
19.Mutation: This is the permanent alteration done to the genetic make up of an organism. It leads to formation of new characters, body shape, skin colour, height and so on. And note that the new characteristics generated from mutation are transmittable and can be inherited.
Thank you for your time!!
