Cytoplasmic Inheritance

a. Present in males and females.

b. Usually inherited from one parent, typically the maternal parent.

c. Reciprocal crosses give different results.

d. Exhibit extensive phenotypic variation, even within a single family.

TLS Online TPP Program

#Id: 1522

#Unit 2. Cellular Organization

Hard keratins make up hair and nails. These keratins are rich in cysteine residues that become oxidized to form disulfide bridges, thereby strengthening the proteins.

TLS Online TPP Program

#Id: 1523

#Unit 2. Cellular Organization

Primary building block of intermediate filaments is a dimer held together through the rod domains, which associate as a coiled coil.

TLS Online TPP Program

#Id: 1524

#Unit 2. Cellular Organization

Two dimers 

Tetramers

Protofilaments (Tetramers are assembled end to end)

Protofibril (Four protofilaments)

10-nm filament (Four protofibrils associate side

TLS Online TPP Program

#Id: 1525

#Unit 2. Cellular Organization

TLS Online TPP Program

#Id: 1526

#Unit 2. Cellular Organization

Microtubules can be stabilized by side-binding microtubule associated proteins (MAPs).

TLS Online TPP Program

#Id: 1527

#Unit 2. Cellular Organization

The short (∼20 amino acid) C-terminal tails of both α- and β-tubulin that protrude from the microtubule are enriched in glutamic and aspartic acids, the surface of the microtubule possesses a net negative charge.