EMS causes ethylation of the bases in DNA at the 7-N and the 6-O positions of G cause G:C → A:T transitions.

TLS Online TPP Program

#Id: 3665

#Unit 3. Fundamental Processes

Size comparisons show that the ribosome is large enough to bind tRNAs and mRNA.

TLS Online TPP Program

#Id: 8640

#Unit 2. Cellular Organization

In vertebrates, Rb is the major guardian of the cell cycle, integrating information about DNA damage and cell growth

TLS Online TPP Program

#Id: 2198

#Unit 10. Ecological Principles

Character                         early stage         late stage 

Root to shoot ratio                    high             low

Number of seed                         many            few

Seed size                                     small            large

Biotic potential                           high             low

Productivity per biomass           high             low

NPP                                              high             low

P/R ratio                                        >1               =1

Nutrient cycling                       open             closed

Importance of detrivores          less              more

Stratification                               No               Yes 

Regeneration ability                 more              less

Resistance ability                        less              more

TLS Online TPP Program

#Id: 1975

#Unit 10. Ecological Principles

If this ratio R is equal to 1, then the population is randomly dispersed.

If R is significantly greater than 1, the population is evenly dispersed

If R is significantly less than 1, the population is clumped

TLS Online TPP Program

#Id: 5923

#Unit 3. Fundamental Processes

To replace the RNA primers with DNA, an enzyme called RNaseH recognizes and removes most of each RNA primer. This enzyme specifically degrades RNA that is base-paired with DNA. RNase H removes all of the RNA primer except the ribonucleotide directly linked to the DNA end.

This is because RNaseH can only cleave bonds between two ribonucleotides. The final ribonucleotide is removed by a 5’ exonuclease that degrades RNA or DNA from their 5’ ends.