Position effect variegation (PEV) 

TLS Online TPP Program

#Id: 3802

#Unit 5. Developmental Biology

During growth, unicellular D. discoideum monitor their cell density relative to that of their bacterial food source by secreting a glycoprotein called prestarvation factor at a constant rate.

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#Id: 450

#Unit 2. Cellular Organization

All four core histones show a similar type of structure in which three a-helices are connected by two loops. This highly conserved structure is called the histone fold.

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#Id: 4820

#Unit 13. Methods in Biology

The confidence level represents the proportion (frequency) of acceptable confidence intervals that contain the true value of the unknown parameter.

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#Id: 2633

#Unit 13. Methods in Biology

The probe must span the sequence where the transcript starts or ends. After hybridizing the probe to the transcript, one applies S1 nuclease, which degrades only single-stranded DNA and RNA. 

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#Id: 9785

#Unit 6. System Physiology – Plant

R gene Mi-1 confers resistance to aphids and whiteflies

Rice R gene Bph14 confers resistance to the brown plant hopper

Melon R gene Vat confers resistance to the cotton aphid. 

All of these R genes encode NBS–LRR receptors.