The receptor (Pacinian corpuscle) converts mechanical energy into an electrical response, the magnitude is proportional to the intensity of the stimulus. Thus, the responses are described as graded potentials rather than all-or-none

TLS Online TPP Program

#Id: 2082

#Unit 8. Inheritance Biology

A reciprocal translocation between the long arm of chromosome 22 and the tip of the long arm of chromosome 9 . This translocation produces a shortened chromosome 22, called the Philadelphia chromosome

TLS Online TPP Program

#Id: 6421

#Unit 8. Inheritance Biology

Pedigree

Pictorial representation of a family history outlining the inheritance of one or more traits or diseases.

TLS Online TPP Program

#Id: 6422

#Unit 8. Inheritance Biology

Autosomal Recessive Traits

Autosomal recessive traits normally appear with equal frequency in both sexes.

The trait seems to skip generations.

When both parents are heterozygous, approximately one-fourth of the offspring are expected to express the trait.

Recessive traits appear more frequently among the offspring of consanguineous matings.

Example - Tay–Sachs disease, sickle cell anemia, cystic fibrosis, PKU

TLS Online TPP Program

#Id: 6423

#Unit 8. Inheritance Biology

Autosomal dominant 

Traits appear in both sexes with equal frequency.

Both sexes are capable of transmitting these traits to their offspring.

An affected person has an affected parent (unless the person carries new mutations). 

The trait does not skip generations.

Unaffected people do not transmit the trait. 

Example- familial hypercholesterolemia, Huntington disease, Neurofibromatosis

TLS Online TPP Program

#Id: 6424

#Unit 8. Inheritance Biology

X-Linked Recessive Traits 

X-linked recessive traits appear more often in males than in females and are not passed from father to son.

Example – Hypophosphatemia , Rett syndrome

TLS Online TPP Program

#Id: 6425

#Unit 8. Inheritance Biology

X-Linked Dominant Traits

X-linked dominant traits affect both males and females. 

Although they often appear more frequently in females than in males.

Affected males must have affected mothers (unless the males possess a new mutation), and they pass the trait to all their daughters.

Affected daughters must have either an affected mother or an affected father.

X-linked dominant traits do not skip generations.