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SWITCH FROM RNA TO DNA. "According to the RNA World Hypothesis, life later evolved to use DNA and proteins due to RNA's relative instability and poorer catalytic properties, and gradually, ribozymes became increasingly phased out." https://lnkd.in/eeUzYdR View in LinkedIn

RIBOZYME-LIKE FIRST CELLS. "Something like these capabilities of ribozymes had to have been components of the first cells. The metabolism of the first cells functioned without feeding. Photoautotrophic and chemoautotrophic organisms do not need to feed: they obtain their energy from sunlight or from hydrogen-rich compounds." https://lnkd.in/eDswHmC View in LinkedIn

INFORMATION PROCESSING. "RNAs play complementary roles in information processing and regulation. In most cases they have an inheritable status, being integrated in the genome of organisms, and are termed endogenous. In other cases they are ancient individuals living in the cytoplasm of cells as persistent nonlytic parasites similar to DNA settlers, with important endosymbiotic roles." https://lnkd.in/euyhznh View in LinkedIn

SO ENDS this two week venture into the subject of flower opening and closing. Flowers arose in order to achieve fresh genetic recombination through sharing genes, by sexual reproduction. Perhaps the biggest driver in the natural world is the generation of ever better adapted genes, niche exploitation, and success of that species. Flowering plants have excelled at all three. View in LinkedIn

OSCILLATING GENES. "Circadian factors affect hormone concentrations. For example, cytokinin, auxin, and ABA concentrations show diurnal patterns. TANDEMZINC KNUCKLE/PLU3 (TZP) affects diurnal growth patterns. Its gene expression oscillates, with a peak in the morning. TZP regulates the expression of auxin-related genes." https://lnkd.in/eTEzGE9 View in LinkedIn

CLOCK GENES. "In Arabidopsis and other plants, several genes with a circadian expression pattern have been identified, for example, a catalase, cysteine protease, a putative β‐amylase, nitrate reductase, sucrose phosphate synthase, and chlorophyll a/b binding proteins (Cab) of photosystems I and II." https://lnkd.in/eTEzGE9 View in LinkedIn

RHYTHM SLIPS. "When plants of Cereus grandifolius (a night‐bloomer) were kept in darkness during the day and exposed to light at night, the normal periodicity was retained for some days but gradually became weaker, and then assumed a new phase in which opening occurred at the end of the light period." https://lnkd.in/eTEzGE9 View in LinkedIn

RHYTHM FLIPS. "In light/dark (LD) cycles of 6 h or 9 h, flower opening followed the imposed cycle (i.e. they were 6 h open and 6 h closed, etc). Interestingly, if the light and dark periods were made as short as 2 h, the flowers again showed a 24 h rhythm. Within limits, therefore, the endogenous rhythm can become entrained by shorter light/dark cycling. Entrainment is defined as the process whereby the plant, exposed to repeated periods of light and darkness with a period P, changes its rhythm to the same period." https://lnkd.in/eTEzGE9 View in LinkedIn

REPLICATION ERRORS. "If information is really only physics and chemistry, then replication can only form identical copies. If changes occur that vary the master copy, the correct designation is error. Therefore, mutation as error replication is the appropriate term, because it is a statistical event, randomly derived." https://lnkd.in/bpZMBAH View in LinkedIn

IMMUNITY TO RETROVIRAL INFECTIONS. "As intron-rich linear chromosomes are the preferred habitat for persistent retroviral infections, and because of their important role in host-genetic content (re) arrangements, the invention of bacterial circular genomes must have had an effective immune function against retroviral infections. The result was the evolution of organisms that successfully escaped the high selective pressures of the early RNA world." https://lnkd.in/ekWBG2q View in LinkedIn