Congenital Deafness in Humans Is Due to the Homozygous Condition

question 83

Short Answer

Congenital deafness in humans is due to the homozygous condition of either or both of the recessive genes d or e . Both dominant D and E are necessary for normal hearing. Gene D/d affects the middle ear, while gene E/e affects the inner ear. It does not matter how good the normal inner ear (as indicated by E _) is; if there is something wrong in the middle ear, the individual is unable to hear. The same applies for the other gene. Give the phenotypic results of the following crosses:
(a) Dd EE x Dd EE
(b) Dd Ee x Dd Ee
(c) dd EE x DD ee
(d) Dd EE x Dd ee
(e) Dd EE x DD Ee

---

Definitions:

Protoplasts

Cells that have had their cell wall removed, exposing the plasma membrane and allowing for study or manipulation of cellular processes.

Runners

A type of plant stem that grows horizontally over the ground and can produce new plants at its nodes, a method of asexual reproduction.

Virtualization

Using specialized software to make individual physical servers behave as though they are more than one physical device.

Specialized Software

Programs designed to meet the specific needs of particular user groups or fields, unlike general-purpose software.