In resting cells

Phospholipid scramblase XKR8 and TMEM16F would equilibrate phosphatidylserine in both plasma membrane leaflets, is inactive.

TLS Online TPP Program

#Id: 3501

#Unit 2. Cellular Organization

Interrupted genes are longer than its mature RNA product because of the presence of the introns hence Length of precursor RNA (not mRNA) defines region of gene

TLS Online TPP Program

#Id: 3502

#Unit 2. Cellular Organization

Interrupted gene: Mutations in exons can affect polypeptide sequence; mutations in introns can affect RNA processing and hence may influence the sequence and/or production of a polypeptide.

TLS Online TPP Program

#Id: 3503

#Unit 2. Cellular Organization

Single-base substitutions at the junctions between introns and exons causes an exon to be left out of the product or an intron to be included, or make splicing occur at a different site.

TLS Online TPP Program

#Id: 3504

#Unit 2. Cellular Organization

In multicellular eukaryotes most genes are interrupted, and the introns are usually much longer than exons, so genes are considerably larger than their coding regions.

TLS Online TPP Program

#Id: 3505

#Unit 2. Cellular Organization

Parity rules by Erwin Chargaff

Rule of complementarity (First parity rule)

Rule of Equal amount applies more closely to introns than to exons (Second parity rule)

Cluster rule – Purines in nontemplate strand applies more closely to Exons (Third parity rule)

GC Rule- GC content tends to be greater in exons than in introns (Fourth parity rule

TLS Online TPP Program

#Id: 3506

#Unit 2. Cellular Organization

Potential for secondary (hairpin) structure is found to be greater in introns than exons