Seven genes have been identified in which mutations give rise to XP, these genes specify proteins (such as XPA, XPC, XPD, XPF, and XPG;)

TLS Online TPP Program

#Id: 9816

#Unit 6. System Physiology – Plant

PRD domain of phyA cannot act as an NLS, so to transport it into the nucleus requires FARRED ELONGATED HYPOCOTYL1 (FHY1) and its homolog FHY1-LIKE (FHL),

TLS Online TPP Program

#Id: 9817

#Unit 6. System Physiology – Plant

Phytochrome responses fall into three major categories based on the amount of light they require: very low fluence responses (VLFRs), low-fluence responses (LFRs), and high-irradiance responses (HIRs).

TLS Online TPP Program

#Id: 9818

#Unit 6. System Physiology – Plant

VLFRs are non-photoreversible.

TLS Online TPP Program

#Id: 9819

#Unit 6. System Physiology – Plant

Arabidopsis seeds can be induced to germinate with red light in the range of 0.001 to 0.1 μmol m–2 at very-low-fluence responses (VLFRs).

TLS Online TPP Program

#Id: 9820

#Unit 6. System Physiology – Plant

LFRs is found at red region (660 nm) and (720 nm) includes processes such as the promotion of lettuce seed germination, inhibition of hypocotyl elongation, and regulation of leaf movements.

TLS Online TPP Program

#Id: 9821

#Unit 6. System Physiology – Plant

A brief pulse of red light will induce a response, provided that the light is sufficiently bright, and conversely, very dim light will work if the irradiation time is long enough. 

This reciprocal relationship between fluence rate and time is known as the law of reciprocity