R:FR ratio and seed germination,

large-seeded species, with ample food reserves to sustain prolonged seedling growth in darkness (e.g., underground), do not require light for germination.

TLS Online TPP Program

#Id: 418

#Unit 2. Cellular Organization

H2AZ variant has 60% sequence identity with canonical H2A and involved in gene activation, heterochromatin–euchromatin boundary formation, cell-cycle progression.

TLS Online TPP Program

#Id: 419

#Unit 2. Cellular Organization

Mammalian macroH2A is enriched in the inactive X chromosome in females, which is assembled into a silent, heterochromatic state

TLS Online TPP Program

#Id: 420

#Unit 2. Cellular Organization

Mammalian H2ABbd variant is excluded from the inactive X and forms a less stable nucleosome than canonical H2A

TLS Online TPP Program

#Id: 421

#Unit 2. Cellular Organization

The nucleosome is 200 bp of DNA, organized by an octamer of small, basic histone proteins into a beadlike structure. 

TLS Online TPP Program

#Id: 422

#Unit 2. Cellular Organization

The nucleosome is of 10nm/100A diameter, compacting the DNA about 6-fold over the length of naked DNA. Its first level of organization. 200X3.4A=680A

TLS Online TPP Program

#Id: 423

#Unit 2. Cellular Organization

The second level of organization is the coiling of the 10-nm fiber of nucleosomes into a helical array to constitute the fiber of diameter 30 nm.