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SubjectFree lesson

Family Traits I

ClassNotes Team 2 MIN READUPDATED 27 JUN 2026

 

Basic Science JSS3 First term

Sub-theme: learning about our environment

WEEK 1

Family traits I

Performance objectives

Students should be able to:

  1. Mention some traits that run in the family
  2. Distinguish between dominant and recessive traits.

Content

Family traits (genetics)      

Genetics is the study of hereditary and variation in living things. The study of hereditary or how the characters of living things are transmitted from one generation to the next. Every living thing contains the genetic material that makes up the DNA molecules. This material is passed on when organisms produce. The basic unit of hereditary is the gene.

Genetics is the process of a parent passing a certain gene to the children. A person’s height, hair color, skin color, eye color, is determined by genes. Other characteristics affected by hereditary include:

Mental abilities

Natural talents

Likelihood of getting certain diseases

Hereditary

This is the transfer of characters from parent to offspring via gene. It is responsible for the similarities between parents and offsprings it is also defined as the transmission of traits from ancestors to descendants through molecular mechanisms lying primarily in the DNA or RNA of the genes.

Variation

This is defined as the difference which exists between parents and offspring. Variation is any difference between cells, individual organisms, or groups of organisms of any species caused either by genetic difference or by the effect of environmental factors on the expression of the genetic potentials. Therefore, family traits are those inherited traits that show variation among members of the family. Some characters that are genetically transferred from parents to offspring include skin, color, height, size of the nose, som genetic disease such as albinism, sickle cell anemia, color blindness, etc.

Dominant and recessive traits

Dominant traits: these are traits that keep appearing in successive generations.

Recessive traits: these are traits that are present in a living organism yet they do not appear physically. Because of the dominant trait in the offspring, but may suddenly appear in successive generations.

Difference between dominant and recessive traits

  1. Dominant traits are controlled by a dominant gene while recessive traits are controlled by a recessive gene
  2. Dominant traits are manifested outwardly while recessive traits are not manifested outwardly