Difference Between Heredity And Inheritance

Fundamental biological concepts like heredity and inheritance help us to understand how genetic information is passed from generation to generation and explain how transmission of genetic elements, traits and characteristics within families and populations are interpreted.

Table of Contents:

What is Heredity?
What is Inheritance?
Types of Inheritance
Key Differences Between Heredity and Inheritance
Problems Linked with Heredity and Inheritance
Future of Heredity and Inheritance
Practice Problems
Frequently Asked Questions

What is Heredity?

As per the scientific definition of heredity, genetic makeup influences specific traits and features more than the environment. For example, tanning is not genetic but has an environmental influence on the body, while the eyes' colour indicates the offspring's hereditary character.

Heredity and biological inheritance are commonly used together but have major differences. The word inheritance came from the Latin word ‘Heridat’. The ribonucleic acid (RNA) molecules carry the genetic information, which codes for a wide range of distinct proteins. The life patterns you observe are the interaction between proteins and the surroundings or environment.

The sophisticated process of DNA replication and reproduction leads to the emergence of a wide range of life forms, resulting in undergoing mutation and recombination of cells in an organism. DNA is the key component for heredity in all eukaryotes, even in bacteria. The theory of evolution by two scientists, Charles Darwin and Alfred Wallace, has best explained the concept that covers how and why each distinct trait is influenced.

What is Inheritance?

Inheritance is the phenomenon that involves the transmission of genetic information from one generation to another. Modern knowledge of inheritance relies on the work attributed to the scientist Gregor Mendel, who worked on inheritance laws while residing in the monastery. He is well-known as the father of genetics.

Sex cells involve DNA which transfers information as molecular instructions, which further is helpful in the reproduction of an organism. During the reproduction phase of human beings, genetic material from both maternal and paternal sides is joined and passed on to a single individual. Even upon inheriting genetic information from both parents, the offspring holds some traits and characteristics which are predominant from each parent.

Types of Inheritance

There are four types of inheritance. They are as follows.

Complete Dominance

In complete dominance, the dominant allele ensures that the expression of the recessive cell is concealed in the inheritance pattern. Allele is one or two distinct variants of the same gene. For example, suppose orange and yellow flowers are crossed. In that case, the dominant one will be expressed with the phenotypic ratio 3:1 and the genotypic ratio 1:2:1, where 1 represents one homozygous dominant, 2 represents heterozygous alleles, and again 1 represents the homozygous recessive allele.

Incomplete Dominance

In the case of heterozygous offspring, incomplete dominance involves equality in genotypic and phenotypic characteristics. It is because they exhibit intermediate features. Thus, each genotype in incomplete dominance has its phenotype. It is called partial or semi-dominance.

Genotype is the genes that occur in the organism, whereas phenotypic characteristics involve the physical appearance of an organism. Heterozygous offerings involve the presence of two distinct alleles for a characteristic in the offspring. On the other hand, homozygous offspring involve two similar alleles representing a trait in the offspring. For example, if a red and white flower cross together, they will form a pink flower. The phenotypic and genotypic ratio in incomplete dominance will be 1:2:1.

Incomplete Dominance

Image: Incomplete Dominance

Codominance

In codominance, both a and b alleles are expressed, which does not represent or mask their dominance. For example, if red and white flowers are crossed, the result will be a combination of red and white flowers. The phenotypic and genotypic ratio in codominance will be 1:2:1.

Incomplete Dominance and Codominance

Image: Incomplete Dominance and Codominance

Sex-Linked

Sex-linked is a type of inheritance which involves the presence of genes in the sex chromosome. Thus, the X chromosome tends to have more genes than the Y chromosome. The ratio will be 1:1.

Key Differences Between Heredity and Inheritance

Heredity	Inheritance
Sexual and asexual characteristics are passed on to offerings.	Genetic information is passed on from parents to offerings.
Genetic information is acquired from parents by offerings.	Genetic information passes by DNA in the form of chemical codes.
Zygote is formed by the fusion of the mother’s egg and the father’s sperm, consisting of genetic information from both the maternal and paternal sides.	Chromosomes pass on genetic materials.
Traits are passed on to offerings and then transferred to their generations.	Each gamete plays a role in sexual reproduction involving their contribution to the production of genetic material.
Traits like eye colour, complexion, height, and intelligence are expressed.	Diseases like haemophilia can be passed on in inheritance.

Problems Linked with Heredity and Inheritance

Numerous disabilities and disorders are caused due to alterations or mutations in the genes or chromosomes during reproduction. Certain genetic abnormalities are directly inherited, while others are a bit complex.

Single Gene Abnormalities

The abnormalities occur due to the mutation in a single gene. The diseases caused due to single gene alteration are sickle cell anaemia, cystic fibrosis and Huntington’s disease. The abnormalities can either be dominant or recessive.

Chromosome Abnormalities

Chromosomal abnormalities occur due to the chromosome's change in structure or number. For example, trisomy 21, also called Down syndrome, is caused due to a copy of chromosome 21. The abnormalities occur during the fault in the distribution of chromosomes while the division of cells.

Multifactorial Abnormalities

The anomalies caused due to genetics along with environmental factors influence multifactorial abnormalities. The interactions between multiple genes and environmental factors trigger deadly diseases like cancer, diabetes and cardiac disorders. These anomalies possess complex inheritance patterns that frequently combine hereditary genetic traits with environmental factors.

Future of Heredity and Inheritance

Advancements in genetics, epigenetics, stem cells, and molecular biology have influenced a positive approach to finding a deeper understanding of heredity and inheritance. Projects like The Human Genome Project and CRISPR-Cas9 enabled scientists and researchers a remarkable approach to finding the genes and their functions better and correcting or modifying the abnormal genes with updated technologies. It helped individuals a lot in treating their genetic abnormalities.

Furthermore, ongoing research on stem cells and epigenetics favour heredity, and interference has positively impacted an individual’s health by understanding the interlinks between nature and gene expression.

Practice Problems

Q1. Who is the father of genetics?

A. Gregor Mendel
B. Carl Linnaeus
C. Rachel Carson
D. Francis Crick

Ans. A. Gregor Mendel

Gregor Mendel was a scientist popularly known as the father of Genetics.

Q2. Who introduced the word Genetics?

A. Rachel Carson
B. William Bateson
C. Gregor Mendel
D. Francis Crick

Ans. B. William Bateson

Willian Bateson introduced the term Genetics in 1905.

Q3. Genetics is the study that deals with

A. Heredity
B. Variation
C. Genes
D. All of the above

Ans. D. All of the above

Genetics involves the study of heredity, inheritance, genes, chromosomes and gene variations and external factors affecting organisms.

Frequently Asked Questions

Q1. Who is the father of Biology?
Answer: Aristotle is popularly known as the father of Biology. And also the father of Zoology, a branch of biology dealing with animals and humans.

Q2. What is a double helix in DNA?
Answer: Double helix shapes the deoxyribonucleic acid (DNA). It is the arrangement of nucleotides in two long strands forming a spiral-like structure.

Q3. State the function of the protein.
Answer: Proteins are needed to properly structure, regulate and function the body's cells, tissues and organs.