A family trait is a genetic likeness that is passed through the parents” genes to their children or offspring. The traits that are being inherited are present in form of genes. Genes are the hereditary unit.
The characters or traits that can be passed from the parents to the offspring include the following;
I- Skin colour( dark or fair)
ii-Height (tallness or shortness)
iii- Colour of the skin, hair, eye iris colour
Iv-Shape of the face, eye ball, mouth, eyelashes, lips, forehead, head, ears etc
v- Method or style of walking.
Vi-Quantity of hairs on the head, body, eyebrow and eye lashes.
Vii-Voice
Viii-Abnormalities such as albinism, sickle cell anemia, colour blindness, hemophilia.
Dominant Trait is trait that keeps on appearing among the family in each successive generation. For instance, if a dominant tall man with dominant gene (TT) Maries a tall woman who has a recessive trait for shortness (Tt). If they produce four children all of them will be tall. This shows that the gene for tallness is dominant over the gene for shortness.
Recessive Traits are those traits that are still present in an organism but do not appear physically because of dominant gen e may suddenly appear in successive generation. For example, if a tall man Maries a short woman may not produce any short child. But their children the recessive traits or genes may produce short children in the second generation.
All the offspring are tall with recessive gene.
3 children are tall, 1 child is short.
Differences Between
| Dominant Gene
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Recessive Gene
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| 1.It is able to express itself even the presence of recessive gene
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It is unable to express its effects in the presence of dominant gene
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| 2.It does not require another to produce its effect on phenotype
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It produces its phenotypic effects only in the presence of similar gene |
| 3.Domnant gene can form complete polypeptide or enzyme for expressing its effects
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Recessive gene forms an incomplete or defective polypeptide or enzyme so that the expression consists of absence of dominant gene. |
Importance of Family Trait
-It helps us to understand some genetic disease.
-It can be used to trace family genealogy.
-It can used to trace the manifestation of physical character such as colour of the eye, skin, hair, body size and height
-The knowledge of family trait can be used to detect crime by finger print or DNA test.
-Good trait such as intelligent and other good traits are continuously being transferred in a family.
ASSIGNMENT
- Which of the following is not a trait that is transferred genetically from parents to offspring? A. skin colour B. height C. colour blindness . D. Smoking
2.Variation like height and skin colour among members of the same family that change from one end of the scale to the other are A. recessive B. Continuous C. discontinuous. D. Genotype
- The genetic make-up of an individual can be altered by A. the environment B. enzymes C. exercise D. food
- Which of these is a genetic disease? A. sickle cell anemia Malaria C. headache Kwashiorkor
5.Which of the following is not a physical characteristics in family trait? A. skin . B. hair. C. Dentition D. height
6.A trait that appears in successive generation is called A. recessive Dominant trait Physical trait D. genotype
7.Family traits are important to all of the following except in A. intelligence. B. Disease control C.resenblance D. hunger control
8a. Define family trait
state two significance of family traits to intending couples
- State two differences between dominant and recessive genes
state five examples of traits that can be transferred from parents to offspring.
See also